Solutions for application in the communal energy infrastructure
2 | LEGAL NOTICE
This work is published in support of the
German-Russian Energy Dialogue.
Deutsche Energie-Agentur GmbH (dena)
German Energy Agency
Chausseestrasse 128 a
10115 Berlin, Germany
Tel: +49 (0)30 66 777 - 0
Fax: +49 (0)30 66 777 - 699
Nikias Wagner, dena
Project Director, International Cooperation
German Lewizki, Sunbeam Communications
Eva Augsten, Sunbeam Communications
Ina Röpcke, Sunbeam Communications
Tibor Fischer, dena
Laurence Green, dena
Design and Implementation
Sunbeam Communications, Berlin
Please cite as
German Energy Agency (dena, 2021): Renewable Energy,
Solutions for application in the communal energy
Version as of
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List of Figures
10: shutterstock/Nikolai Link
20: shutterstock/Mike Fouque
22: shutterstock/Wolfgang Jargstorff
11, 13, 17, 21, 23: Sunbeam Communications
26, 29, 31: German Energy Agency (dena),
Renewable Energy Solutions Programme/
Немецкое Энергетическое Агентство dena
27: ALC ENECA/ОДО «ЭНЭКА»
28: Solarimo GmbH
30: Hevel Group/ГК Хевел
32: FASA AG, The Case Digital
33: Ingenieurbüro für Energieeffizienz, Wolfgang Hilz
35: Kraftwerk Himmelpforte - Gebr. Hennecke,
36, 41, 42: Department for Energy Efficiency of the
State Committee for Standardization of the Republic
of Belarus/Департамент по энергоэффективности,
Государственного Комитета по стандартизации
37: Ecoklimat LLC/ООО Экоклимт
38: Leningrad Oblast Energy Saving and Energy
Efficiency Centre/ГКУ ЛО «Центр энергосбережения
и повышения энергоэффективности
39: Fortum Corporation
40: Siemens Gamesa Renewable Energy
43: Bioenergiepark Forst
44: Förderverein des Neue Energien Forum Feldheim e.V.
45: Sedum Architects
Executive Summary 4
Think globally, benefit locally 5
The Energy Transition 6
Application options 8
Photovoltaics – electricity from sunlight 10
Solar thermal energy – heat from the sun 12
Hydropower – electricity from the river 14
Near-surface geothermal energy – energy from the ground 16
Wind power – high-tech with tradition 18
Biomass – stored solar energy 20
Biogas – stored solar energy to gas 22
Project overview 24
Mongolia: Hybrid plant supplies electricity for rural training center 26
Belarus: Solar power plant secures power supply 27
Germany: Cheap solar power for tenants 28
Kyrgyzstan: Solar power for a children’s home 29
Tuva: Solar diesel hybrid system for remote villages 30
Uzbekistan: Tashkent University uses solar power 31
Germany: Plenty of solar heat for apartment buildings 32
Germany: Solar heat network of old and new buildings 33
Kabardino-Balkaria: Small hydropower plant with secure returns 34
Germany: Modernisation of a small hydropower plant 35
Belarus: Heat from the earth, electricity from the sun 36
Russia: Secondary school heats its buildings with geothermal heatpumps 37
Russia: School cuts heating costs to a quarter with geothermal energy 38
Russia: Wind farm strengthens research and creates jobs 39
Poland: Wind power replaces lignite 40
Belarus: Electricity and district heating from woodchip 41
Belarus: Wood-fired heating plant reduces district heating costs 42
Germany: Electricity, gas and heat from chicken manure and energy crops 43
Germany: “Bioenergy village” Feldheim supplies itself with wind, sun and biogas 44
Georgia: Small hydropower helps to support tourism 45
Further contact information 46
4 | EXECUTIVE SUMMARY
This brochure contains a selection of successful renewable energy solutions suitable for a range of applications
for local and national municipalities and economies. The main energy end-use sectors and the current
state of the energy transition are briefly explained to provide readers with an understanding of the transformation
of the greater energy system. The renewable energy technology options are explained, including
their relevance and applications for municipalities. Finally, a selection of exemplary projects that have been
successfully implemented in Europe, the Russian Federation and Central Asia, are included to demonstrate
real applications and use-cases for renewable solutions. Renewable energies are cheap, clean and versatile.
• Globally, the generation capacity of renewable
energies has been growing faster than the capacity
associated with fossil generators for several years.
• Solar energy is suitable for the completely emissionfree
generation of electricity and heat. It can also be
generated on house roofs in cities.
• The costs are steadily decreasing: Wind and solar
power are already cheaper than fossil energy sources
in many places.
• Communities that use renewable energy benefit from
cleaner air and less noise.
• Renewable energy sources are local energy sources.
They increase the level of added value locally.
They reduce fuel imports and create jobs.
• Industrial companies often rely on renewable
energies to hedge against rising electricity prices.
• Depending on demand, electricity, heat or fuels can
be generated from renewable sources.
• Each region has individual energy resources that
need to be harnessed: Solar, wind, bioenergy,
hydropower or geothermal energy. In remote locations
without a grid connection, wind and solar
power – in combination with batteries – are inexpensive
alternatives to diesel generators.
• Wind farms can supply very large amounts of
• Wood and other solid biomass are suitable for heating
and for generating electricity in power plants.
Wood chips and pellets burn very cleanly in modern
• Biogas can be produced from energy crops (e.g. maize),
but also from waste. It consists mainly of methane
and is used in a similar way to natural gas.
• Hydropower plants come in all sizes.
They generate electricity around the clock.
• Geothermal energy (geothermal heat) is mostly used
together with heat pumps for heating.
There is also potential for geothermal power plants
in some areas.
• Depending on the climate, buildings have a high
energy demand for heating and cooling. Modern
insulation – in combination with renewable energies
such as solar heat or geothermal energy – help to
Think globally, benefit locally
Wind power, solar energy, geothermal energy, biogas
and biofuels – renewable energies are on the rise
around the world. Just 20 years ago, they were a niche
product, but today their expansion rates exceed those
of fossil energy sources. This is partly due to the
ever more visible and severe consequences of climate
change. Increasingly frequent weather extremes – such
as droughts and floods – have pushed the energy transition
up the political agenda. In addition to advances
in technology and a reduction of costs, the success of
renewable energy sources is also due to the fact that
they offer great benefits at the local level.
The use of renewable energy sources such as wind
and solar energy not only produces no CO 2 , but also
no harmful emissions such as fine dust and nitrogen
oxides. Municipalities can immediately benefit from
better air quality when power generation, heating and
mobility are switched to clean energy sources.
In addition, renewables also offer new opportunities
for the regional economy. Every region is characterised
by its own specific energy potential. In one area, there
may be high solar radiation, while in another there is
abundant wind energy, and in other places there are
high resources of biomass and other residual materials.
Using this potential is economically attractive for municipalities
in several respects. By supplying municipal
or community facilities with renewable energy solutions,
the municipality and the institutions themselves
can first benefit from favourable energy costs. A children’s
home in Bishkek (the capital of Kyrgyzstan), for
example, previously spent a large part of its budget on
electricity. The new photovoltaic system saves energy
costs and leaves more budget for the primary activities
of the home.
The construction of renewable energy plants also creates
jobs in local trade enterprises and planning offices.
Many technologies, including primary and secondary
components, can also be manufactured locally in whole
(or at least in part). Regions with particularly favourable
conditions can, in turn, become energy exporters,
for example, with wind power or biofuels, and thus
generate additional income. Renewable energy projects
also allow relevant expertise to be nurtured and developed
at the local level. The solar plant located on the
grounds of the State Technical University “Abu Rayhan
Beruni” in Tashkent (the Capital of Uzbekistan) not
only provides renewable and reliable energy, but also
serves to demonstrate and educate students and other
interested parties on renewable energy technologies.
The decentralised nature of renewable energy is particularly
valuable in remote regions that otherwise rely on
fuel or electricity supply over long distances. At the vocational
training centre of the Mongolian University of
Life Sciences (MULS) in Nart Töv, about 140 kilometres
north of the capital Ulaanbaatar, solar and wind energy,
in combination with a battery storage system, have
replaced the former diesel generator. Instead of having
to pay for (and transport) large quantities of diesel, the
vocational training centre has now created a reliable
and inexpensive energy supply for itself.
The demands on energy supply are wide-ranging, as
are the possibilities of renewable energies. With this in
mind, we hope you discover some interesting insights
into the areas of application and the vast opportunities
that renewable energy sources and technologies offer.
When citizens and businesses utilize and rely on local
renewable energy sources it also benefits the community.
By spending less money on – mostly imported –
fossil fuels, more stays in the region, thereby helping to
boost the local economy.
6 | INTRODUCTION TO THE “ENERGY TRANSITION”
The Energy Transition
Since industrialisation, the consumption of fossil fuels and raw materials has grown steadily. These still cover
the majority of global energy demand. However, the share of renewable energy and energy efficiency in global
investments in the energy sector is steadily increasing and has remained more stable than investments in
conventional energy, even during the Corona crisis. The transition from conventional energy sources to renewable
and sustainable forms of energy is occurring across all sectors, on a global scale.
In 2018, the EU member states obtained around 32 per
cent of their electricity from renewable sources. Climate
protection targets and government funding are only one
reason for this. The other is tangible economic benefits.
The cost of wind and solar energy has fallen so rapidly
over the last twenty years that in many cases, they
are cheaper than fossil energy forms. At the turn of
the millennium, the generation of one kilowatt hour of
solar electricity in Germany cost around 50 cents; today
it is about a tenth of that.
An increasing number of companies are concluding direct
electricity supply contracts with solar system operators
– without government subsidies. Wind power generation
is also growing immensely. In 1997, global wind power
capacity was 7.5 gigawatts; in 2018, it was 564 gigawatts.
Onshore wind farms, in particular, are among the cheapest
forms of electricity generation today. Offshore wind
(wind farms at sea) is somewhat more expensive because
of the special conditions and requirements, but delivers
energy with particular consistency.
The fluctuating renewable energy sources (wind and
solar) are supplemented by controllable forms of renewable
energy – such as bioenergy and hydropower,
and by modern energy storage systems. Today, it is
mainly batteries, but in the future it will increasingly
be renewable energy carriers such as hydrogen.
Another positive effect of the Energy Transition is the
high level of regional added value. Instead of simply importing
fossil raw materials, investments flow into local
economies. In Germany alone, several hundred thousand
jobs have been created in the green power sector.
Much remains to be done in the building sector, which
accounts for about 40% of the EU’s energy demand.
Depending on the climate zone, this includes, above all,
a considerable amount of energy for heating or cooling.
In 2018, the EU decided (in the “energy performance
of buildings directive”) that all member states must
define a standard for new buildings from 2020 that sets
the energy requirement at almost zero. In technical
terms, it has already been possible for years for buildings
to generate more energy than they consume. The
“Solar Settlement at Schlierberg” in Freiburg (Germany),
the residential tower “Elithis Danube” in Strasbourg
(France), the supermarket of the Migros chain
in Zuzwil (Switzerland) and Solar-5 in Vladivostok are
just a few of many examples. Member states must also
present a plan for the reno vation of existing buildings,
as demanded by the EU.
In order for the energy transition in the building sector
to succeed, energy demand must be minimised through
measures such as efficiency standards, highly effective
insulation, and others. At the same time, the demand
must be met with renewable sources where possible.
This can be done, for example, with a heat pump
powered by electricity from a green electricity provider,
or by generating heat or electricity with a solar system
directly on the building. With good planning and
a long-term time horizon, highly efficient houses save
their occupants a lot of money.
INTRODUCTION TO THE “ENERGY TRANSITION” |
In the transport sector, greenhouse gas emissions
in Europe have not fallen since 1990, but have risen
slightly. People and goods travel ever further distances.
Cars and trucks cause by far the most emissions. The
mobility revolution begins in the cities and goes hand
in hand with a new urban lifestyle. In Copenhagen,
people use bicycles for 35 per cent of all journeys, in
Amsterdam 30 per cent and, in the small Dutch town of
Houten, the number is even 44 per cent. On the other
hand, good public transport is essential for longer distances
and for people with limited mobility.
The retail trade also benefits from the mobility revolution,
because fewer cars mean more space for parks,
promenades, beautiful squares and cafés – and these
also attract customers. In rural areas, where many people
still rely on cars today, clean drive motors are the
key, especially electro mobility for passenger cars. In
2019, more than 2.1 million electric vehicles (EV) were
sold worldwide – and the trend is rising. Thanks to developments
in battery technology, the ranges of EVs for
personal mobility today has increased to 500 kilometres
and the purchase costs are only slightly higher than
those of combustion engines. If the EV is “fueled” with
inexpensive, self-generated solar power, the economic
and environmental benefits are even greater.
Industry also needs to become cleaner. Since 1990, European
industry has successfully reduced its greenhouse
gas emissions by 35 per cent. However, most of this
was achieved before 2010. In the last decade efficiency
has continually increased and many processes have
been optimised to such an extent that fundamental
changes in procedures are necessary for further reductions
One step can be the use of electricity and heat from
renewable energies, which can now also be purchased
from specialised companies in direct contracts (power
purchase agreements or heat supply contracting). In
some processes, such as the production of steel, CO 2 is
also produced directly in the production process.
One way out of this could be the use of green hydrogen.
Many companies are showing great interest in climatefriendly
production processes. The changeover is technically
feasible, but it must be taken into account today
when investing in new machinery and equipment in
order to prevent lock-in effects. For this, industry needs
both clear targets and support from policymakers.
Policy plays a vital role in shaping the future, sustainable
energy system. In the EU certain Energy-intensive
industries are part of the European Union Emissions
Trading System (EU ETS). Companies within these industries
may only produce a limited amount of emissions.
If they produce more, additional allowances must
be acquired. For these companies, energy efficiency,
therefore, pays off twice – in terms of energy costs and
in the savings or trading of allowances.
Renewable energy sources are not only clean and cost-effective, but also versatile. This means that every
municipality with its own individual needs can find a suitable solution – from heating a school to providing a
reliable power supply for industrial areas. The below graphic and following technology descriptions help to
identify the right solution. Exemplary projects are then presented, starting on page 24.
Applications Utility scale Industry/Commercial Private household Off-grid
Small wind turbines
Applicable for Heating/cooling
Applicable for Heating/cooling and electricity
Source: dena study: Status and perspectives for renewable energy development in the UNECE region
10 | PHOTOVOLTAICS
Photovoltaics – electricity from sunlight
Photovoltaic systems generate electrical energy from solar radiation – cost-effectively, quietly and without
emissions. In areas with an existing power grid, they reduce energy costs and can provide support for the network;
in regions with an unstable (or even no) power grid, they provide a secure and efficient energy supply
that can also be combined with storage systems for even greater coverage.
Over the past 20 years, solar power generation has
developed into a marketable and economical technology.
In many countries around the globe, the generation costs
for solar power are now lower than those for conventional
electricity. Worldwide, the generation costs for
solar electricity from large solar power plants have fallen
to an average of 50 US dollars per megawatt hour. Ten
years ago, those numbers were well above 300 dollars.
This incredible drop in price follows the expansion of
international production capacities, which was triggered
by an explosion in demand for photovoltaic (PV)
Today even self-generated electricity from smaller solar
systems is often cheaper than electricity purchased from
the electricity network, or electricity generated using
diesel generators. This applies to residential properties
and municipal buildings alike: solar PV systems can be
installed on schools, hospital buildings, recreational
facilities and other public and private buildings to cover
electricity demand in a climate-neutral way.
A typical household in Germany can cover roughly 20 to
30 per cent of its electricity needs with solar power by
using a solar PV system. With a storage system, this can
increase to around 80 per cent. Households in countries
and areas with greater solar resources can cover all of
their electriciy needs with PV systems together with
battery storage. Many battery storage systems also offer
an emergency power supply. If there is a power outage,
the storage system steps in. This is especially important
in applications where a constant power supply is
essential, such as in hospitals and data centres.
In regions without a stable grid connection, diesel
gene rators are often used to supply power. The required
fuel is often transported over longer distances. With a
solar PV system, diesel and transport costs can be greatly
reduced. A solar-diesel hybrid system can ensure supply
of electrical energy in times of low solar energy generation
or during night. With the help of clever design, a
combination of a solar system and battery storage can
ensure power supply even without a diesel generator,
especially in areas with high solar irradiation.
A place for the solar modules can be found in most cases.
These can be installed on roofs, facades and even on
the ground. Once commissioned, the systems can run
almost maintenance-free for decades.
Possible applications and benefits for
Solar PV systems can be installed on most buildings
and in open spaces. They supply solar power for a wide
variety of applications, for example:
• Residential houses of any size
• Municipal, commercial and industrial buildings
• Off-grid consumers and loads, such as remote
facilities or radio masts and equipment
• Charging stations for electric vehicles
• The replacement of diesel generators or for use in
diesel hybrid systems
There, they reduce energy costs and CO 2 emissions and,
especially in connection with energy storage systems,
provide reliable energy even when the public power
grid is unstable. In off-grid locations, “micro grids”
with solar PV plants with or without battery storage
combined with backup diesel generators, can ensure an
efficient and stable energy supply.
Functional principle and design
The primary components of a PV system are the solar
modules which form the solar array. In today’s most
widespread module technology, each solar module
consists of numerous solar cells that utilise silicon as
a semiconductor. These cells are interconnected within
Several modules are combined to form a PV system
and mounted on the roof or ground using a mounting
system. There, they convert solar radiation into direct
current. Inverters are used to convert this into alternating
current, which is fed into the public or private
electricity grid, or it is used directly on site.
To ensure a high solar yield, the PV modules should
be installed facing south if possible. When being used
for individual energy needs only however, east- and
west-facing systems are also well-suited. The modules
should be mounted at an angle, for example, 30 degrees.
It is also important that the system is not shaded,
or only shaded for a brief period. Depending on how
the modules are connected, a shaded area can significantly
reduce the solar yield of the entire system.
Since becoming more cost-effective than electricity
from an energy supplier in some countries, the combination
of solar electricity and a battery storage system
is gaining in popularity. In this case, either the inverter
or an external energy management system regulates
the energy flows. The solar electricity is typically first
consumed directly in the building. Unused electricity
is temporarily stored in the battery for later use or fed
into the public grid depending on the country, market
and relevant regulations.
4 5 6
Structure of a photovoltaic system in a building
1) Solar modules 2) Generator junction box 3) Load
4) Grid connection 5) Meter 6) Grid feed-in unit
In addition to such grid-connected PV systems, offgrid
systems or so-called “micro grids” (off-grid
solutions), require a battery for optimal results. There
are now technically mature battery systems available
for all applications: from small home storage units for
a residential building, to large-scale commercial and
industrial storage units with several megawatt hours of
12 | SOLAR THERMAL ENERGY
Solar thermal energy – heat from the sun
Solar thermal systems generate heat from solar radiation for water heating and room heating in buildings,
for industrial processes and heat networks. The most common use worldwide is for domestic hot water and
solar thermal systems that support central heating. With their glazed solar collectors, the systems are robust,
low-maintenance and remain functional for decades. Free solar energy lowers energy costs and reduces
climate-damaging emissions in heat supply.
Domestic solar thermal hot water systems provide heat
for shower- and drinking water, and are most commonly
used in single-family homes. However, they are,
in principle, suitable wherever there is a high demand
for hot water. That is why hotels and holiday resorts
are also ideal applications for solar thermal systems, as
are retirement homes, hospitals and sports halls. Solar
thermal systems that support heating provide energy
for hot water as well as room heating.
Solar thermal systems can also be integrated into heating
networks, for example, in new development areas,
where they supply residential buildings and municipal
properties centrally with heat. Generally, installation
on roofs is common, but an elevated installation in
open spaces or other structures are also possible.
These applications involve low-temperature systems
for a water temperature of up to approx. 60 degrees.
For industrial and commercial enterprises, there are
process heating systems for high temperatures of approximately
100 degrees Celsius. There is also a need
among companies such as laundries, car washes, painters
and breweries. In agriculture, drying can be done
with the help of solar heat.
SOLAR THERMAL ENERGY |
Design of a solar
in a building
2 3 4
1) Solar collector
2) Solar storage tank
4) Solar controller
Possible applications and benefits for municipalities:
Solar thermal systems convert solar radiation directly
into heat, thus saving costs and reducing CO 2 emissions.
They can be used for:
• Single and multi-family houses,
• Municipal buildings such as kindergartens,
retirement and residential homes
• Tourist buildings such as guesthouses and hotels
• Industrial and commercial processes
• Local and district heating networks
Functional principle and design
At the heart of a solar thermal system are solar collectors
containing absorbers made of copper or aluminium.
These absorbers take in energy-rich short-wave
solar radiation and convert it into usable heat. The heat
is then transferred to a heat transfer medium. This is
usually a frost-proof solar fluid that circulates within
the system. A circulation pump transports the heat
from the collectors through the solar pipes and to the
heat storage tank. Due to the fact that the solar fluid
is in a separate circuit, a heat exchanger transfers the
heat to the domestic or heating water. From the storage
tank, the heat then reaches the hot water distribution
or the heating system.
Robustly built flat-plate collectors are available, which
have the largest market share, as well as more powerful
evacuated tube collectors. Air collectors, a niche product,
can be used for additional ventilation.
In domestic hot water systems, a drinking water storage
tank stores hot water for bathing and washing. In
heating-support systems, either a buffer storage tank
is used that only stores the heating water, or a combination
storage tank where a drinking water storage
tank is integrated into the heating tank.
In the case of a domestic hot water system, it is advisable
to dimension the system in such a way that
the demand for heat in summer is completely covered
by solar energy. The boiler can then remain switched
off during the warmer months and, depending on the
design, in spring and autumn, too.
Heating-support systems must also be scaled proportionately
in accordance with the share of solar heat
to total heating energy. The collectors are aligned in
such a way that they absorb as much solar radiation as
possible during winter. The space required for the heat
storage tank, which is usually installed in the heating
or engineering room, must also be taken into account.
14 | HYDROPOWER
Hydropower – electricity from the river
Of all the renewable energy sources used to generate electricity in Eastern Europe and the Russian Federation,
hydropower has by far the largest share. The electricity is mainly generated by plants in the gigawatt
power classes. But so-called “small hydropower” – with plants of up to 25 megawatts capacity – also delivers
many positive effects as a decentralised, local power supply.
Hydroelectric power really comes into its own, above all,
in remote areas such as mountain regions. There, it is
particularly costly to connect small settlements to the
public electricity grid. Harnessing the power of rivers
enables energy generation from hydroelectric power.
Local electricity supply improves living conditions and
thus creates a basis for further economic development.
In more densely populated areas, a stable electricity
supply promotes the settlement and expansion of industry
and commerce. Hydroelectric power plants, for
example, provide the energy used in the production of
building materials, for irrigation and sewage systems,
and for agricultural operations. Municipal facilities,
such as schools and medical care centres, also receive
reliable electricity in this way.
In addition to the off-grid operation of hydroelectric
power plants, integration into public electricity grids is
also an option. The plants supply constant energy and
can reliably cover the base load and stabilise the grids.
In addition, no greenhouse gases are produced during
this energy generation process, and the municipality
makes a contribution to climate protection.
The Francis turbine is a universally applicable water turbine, in
which the impeller is radially impinged from the outside.
The Kaplan turbine is an axial-flow water turbine and is used in
run-of-river power plants.
Possible applications and benefits for municipalities:
Small hydroelectric power plants with a capacity of
up to approx. 25 megawatts support a wide range of
• Power supply to remote villages and regions
• Improving infrastructure in already developed areas
• Covering the base load in the electricity grid
• Securing the supply of electrical energy
• Stabilisation of the groundwater level
• Reduction of climate-damaging emissions
Functional principle and design
Small hydroelectric power plants are usually run-ofriver
(RoR) power plants. They use the hydraulic energy
of flowing water and continuously convert it into electricity.
Pumped storage plants are to be distinguished
from this. These store the water in a reservoir and
generate electrical energy when needed.
A run-of-river power plant works as follows:
Run-of-river or what are also known as ‘diversion’
power plants may also be contructed to channel or divert
water to the power plant via an additional watercourse
alongside the weir and main water body. The
goal is to achieve a greater gradient in order to achieve
Another important component in the hydro electric
power plant are the rakes. The metal grilles possess
a dual function. Firstly, they protect the turbine from
damage caused by floating refuse – such as branches
and rubbish. Secondly, the small rake distances prevent
fish from entering into the power plant. The mechanical
barrier moves the fish away from their migratory path
with the main current. In order to ensure the continuity
of flowing waters, plant operators often build devices
known colloquially as “fish ladders” at the edge of the
Run-of-river power plants are particularly suitable for
watercourses with high flow velocities. They achieve
very high efficiencies of up to roughly 90 per cent.
The water may first be dammed up at a wier or dam
wall but is not always required. The water upstream of
the power plant (headwater) is higher than the water
downstream of the power plant (tailwater). The steeper
the gradient, the greater the amount of energy generated.
The headwater is fed into the power plant to the turbine.
This drives a generator that subsequently generates
electrical energy (electricity) from the mechanical
energy. After power generation, the tail water flows out
of the plant.
16 | GEOTHERMAL ENERGY
Near-surface geothermal energy –
energy from the ground
In the ground, temperatures remain largely stable throughout the year, even just a few metres below the
surface. With the help of a heat pump, this energy can be used to generate heat in winter and, if required,
for cooling in summer.
The immense energy resources hidden deep inside the
earth are only accessible near or on the surface in a few
places around the world – for example, in Iceland and
in Russia’s Kamchatka peninsula. In these locations
geothermal power plants – instead of burning fossil
raw materials – tap directly into the earth’s energy.
This means they can generate clean electricity and district
heating all year round.
Even though the ground in most parts of the world is
significantly cooler than that found in volcanically active
zones, it is still a clean and reliable source of energy.
With the help of ground-coupled heat pumps, heat from
the ground can be used to keep buildings warm. Using
electrical drive energy, the heat pump “pumps” the heat
into the heating circuit against the temperature gradient.
Essentially, heat pumps are effective when the
temperature in the ground is just a few degrees warmer,
although the system’s efficiency increases with every
additional degree. Instead of the ground as an energy
source, water, wastewater, waste heat
from machines or even, under certain circumstances,
ambient air can also be used. Some heat pumps can also
reverse their operating direction and provide cooling in
summer by transferring heat from the building to the
Nearly 20 million new heat pump heating systems were
installed around the globe in 2019. In many countries,
they are the most common source of heat for new
buildings, e.g. in the USA. In Europe, Sweden, Estonia,
Finland and Norway are the countries with the
highest share of heat pump-based heating. The use of
heat pumps is particularly suitable where clean electricity
is also available. This can be generated centrally
from wind or hydroelectric power, or via photovoltaic
GEOTHERMAL ENERGY |
Surface ground heat absorbers use the heat stored in the
ground. They require a large area and are, therefore, suitable
for larger, undeveloped plots.
For small plots of land or areas with deeper groundwater veins,
geothermal probes aare advantageous.
Possible applications and benefits for municipalities:
Heat pumps can be used where heating energy is required
and heat is reliably available at a low temperature
level. There, they reduce operating costs and CO 2
emissions attributable to room heating:
• Heating buildings of any size with heat
from the earth
• The combination of heating in winter and cooling in
summer (reversible operation)
• The use of waste heat at a low temperature level, e.g.
from machines or wastewater
Functional principle and design
A heat pump-based heating system consists of three
main parts: With the source system, heat is collected
from the ground or another heat source. The heat pump
raises the temperature to the desired level. The distribution
and storage system ensures that the heat arrives in
the right room at the right time.
In order to use the ground as a heat source, horizontal
(geothermal collector) or vertical (geothermal probes)
pipe systems can be deployed. Water mixed with antifreeze
– brine – flows through these systems. The brine
absorbs the heat from the ground, and the heat pump
renders it usable for people.
the building’s heating system. The vaporous refrigerant
transfers its heat to the heating water. It becomes liquid
again and the cycle can begin anew
The closer the temperature in the building’s floor and in
the heating circuit are to each other, the more heat can
be “pumped” into the building with the same amount of
electricity. It is thus important to combine heat pumps
with, for example, underfloor heating or air heating.
These can achieve a comfortable room temperature in
excess of 20 degrees Celsius with heating circuit temperatures
around 35 degrees Celsius – provided the
building is well-insulated. At temperate latitudes, for
example, it is possible to generate more than four kilowatt
hours of usable heating with one kilowatt hour of
electricity, based on an annual average.
So-called reversible heat pumps are also helpful. They
are used for cooling in summer by pumping heat from
the building into the ground by reversing the process
described above. This also has the advantage that the
ground becomes warmer and the heat pump works
more efficiently in winter. As a general principle, good
planning and the coordination of components are particularly
important for heat pumps.
The brine heats the so-called refrigerant in the heat
pump. This is a liquid that evaporates at very low
temperatures. When turned into steam by the heat of
the brine, the refrigerant flows to a compressor. There,
it is compressed with the use of electrical energy. The
gas heats up under pressure. It then meets the medium
of the distribution circuit in a heat exchanger, the
so-called condenser – usually the water circulating in
18 | WIND POWER
Wind power – high-tech with tradition
Engineers have continued in their efforts to improve electricity generation from wind power over recent decades.
Large wind farms, both on- and offshore, can generate enough electricity to supply entire cities. Small
systems are suitable for off-grid villages and settlements.
People have been harnessing the power of wind to
their benefit for centuries, but the boom in wind power
is just a few decades old. In Germany, wind power
contributed in excess of 24 per cent to total electricity
generation in 2019, even surpassing lignite. In Denmark,
where wind energy has long been relied upon
intensively, it even covers almost half of all electricity
demand. Thanks to modern forecasting and control
technology, wind power can be safely integrated into
the electricity grid. In future scenarios developed by
experts, wind energy will play the second largest role in
electricity generation in the long-term – after photovoltaics.
Given the temporal differences in electricity
generating profiles, these two forms of energy complement
each other very effectively.
Due to technological developments and economies of
scale in production, the cost of wind energy has fallen
sharply around the globe and, depending on the region,
costs roughly between 5 and 10 US cents per kilowatt
hour, or 3 cents per kWh under particularly favourable
conditions. Offshore power generation is somewhat
more expensive than its onshore sibling because of the
special requirements that characterise its operation, but
offshore wind conditions allow for more stable generation
Possible applications and benefits for municipalities:
Wind energy is versatile for grid-connected and offgrid
applications spanning various dimensions:
Today’s wind turbines for onshore use can have hub
heights of approx. 150 metres and rated outputs of over
5 megawatts; while offshore installations can exceed
200 metres and produce more than 10 megawatts.
There are several wind farms with several hundred
megawatts of capacity, and even individual projects
operating in the gigawatt range.
• On- and offshore wind farms for feeding into the
• Feeding into micro grids, e.g. for supplying individual
locations, including in combination with solar
power and batteries
• Small wind turbines for special applications (e.g.
• Replacement or supplementation of diesel generators
WIND POWER |
floating foundations. The control technology for the
system is located at the bottom of the tower.
Wind turbines for off-grid applications are often not
only smaller but also technically simpler and more robust
than their larger relatives. They require minimum
maintenance. Many of the small installations do not
involve free-standing towers, but rather masts braced
with steel cables. In addition to the classic three-blade
models, there are also various models with a vertical
Construction of a wind turbine:
1) Rotor blade 2) Blade pitch
3) Blade hub 4) Generator brake
5) Gearbox 6) Measuring instruments
7) Nacelle 8) Generator
9) Transformer station 10) Ascent
11) Cable route 12) Tower
Functional principle and design
Modern wind turbines typically have three rotor blades
made of lightweight and stable fibreglass. The rotor
hub connects the blades and transmits the movement
to the shaft, which leads to the inside of the nacelle situated
at the top of the tower. The nacelle can be rotated
and can, therefore, be aligned according to the wind’s
direction. The rotor blades can also be adjusted, in
order that different wind strengths can be utilised to an
optimum, while damage can be avoided during storms.
The gears translate the slow rotation of the rotor shaft
into the fast movement of the generator.
When planning a wind farm, the first priority is to select
the right location. Wind speed must be measured at
different heights, while the distance and capacity of the
nearest power line must be taken into consideration.
Negative effects on human health have not been proven
to date, but a certain distance from settlements and
houses contributes to their acceptance by the broader
population. In order to protect bird and bat species,
wind farms should also be built outside breeding areas,
bird resting places and nature reserves.
Involving people from the neighbourhood in the wind
farm and its profits – through the purchase of shares –
has also proven successful.
Wind turbines are generally designed to have a service
life of about twenty years. Depending on their condition,
a general overhaul is then due in order to ensure
further years of operation. Alternatively, the turbines
can be dismantled and replaced by a new, more efficient
turbine. This is known as “repowering”. In view
of the fact that the turbines are primarily made of concrete
and steel, the materials can be further recycled in
the usual processes. Recycling processes are currently
being developed for the rotor blades.
In contrast to a photovoltaic system, a wind turbine
supplies alternating current. The wind turbine tower
can be made of steel or concrete. Lattice towers made
of steel require less material than tubular steel towers.
This makes them lighter and cheaper, but also more
complex to assemble. A foundation of steel and concrete
ensures a solid anchoring. There are various special
construction forms for offshore foundations, ranging
from simple piers to gravity-based foundations and
20 | BIOENERGY
Biomass – stored solar energy
Plants use the energy of the sun to grow. Biomass, e.g. in the form of wood, biogas or biofuels, is thus naturally
stored solar energy. This resource can be harnessed cleanly and sustainably with the help of modern
Biomass refers to material that is of plant and animal
origin. The range extends from wood, to energy crops
such as rapeseed and maize, to waste products such
as animal dung or food processing waste. The carbon
contained therein was taken from the atmosphere by
plants and bound with energy from sunlight through
the process of photosynthesis to form hydrocarbons
that can serve as a source of energy. Bioenergy accounts
for roughly three quarters of renewable energy worldwide.
Over half of this involves traditional biomass use,
i.e. the unregulated burning of wood, dung or charcoal.
However, this produces particulate matter and nitrogen
oxides that are harmful to health. The high fuel
demand is also often accompanied by deforestation and
the loss of natural habitats.
Modern wood-based energy, on the other hand, relies
primarily on standardised fuels such as pellets and
wood chips, which enable regulated and clean combustion
processes, thus leading to improvements in local
air quality. Given that residual materials from local
wood processing such as chips or knotted wood are
mostly used for this purpose, local value creation also
increases. Until recently, wood and charcoal provided
just under half of Europe’s renewable energy, especially
in heat generation. In percentage terms, however, their
share is decreasing due to the expansion of wind and
solar energy, as well as other forms of biomass use.
Wood pellet heating systems offer a fully-fledged replacement
for central heating systems. The pellet boiler
works fully automatically and can heat an entire building.
Pellet stoves for installation in the living room, on
the other hand, can serve as a clean replacement for
simple coal stoves. For larger buildings, e.g. schools or
community centres, woodchip heating systems are a
good option. They are a cost-effective option for heating
municipal buildings, especially in rural regions.
Municipal energy suppliers often rely on woodchips to
generate district heating. Coal in power stations and
cogeneration plants can also be partially replaced by
woodchips. In principle, whenever possible, electricity
and heat should be generated together through cogeneration
in order to use the limited raw material of wood
as efficiently as possible.
Functional principle and design
Wood pellets are produced by compressing wood shavings
and sawdust without the use of any other additives.
Pellet plants are often affiliated with sawmills.
The cylindrical pellets are typically about 6 millimetres
thick and 1 to 4 centimetres long. The pellets are characterised
by a higher heating value than wood chips and
contain little moisture.
Pellet boilers are installed in the boiler room like other
central heating systems. The fuel supply from the
store to the burner is managed automatically, as is the
control system. The combustion heat is transferred to
the boiler. From here, the heat is distributed throughout
the building via radiators, as with any other central
heating system. A heat accumulator compensates for
any deviations between heat generation and demand.
In contrast to gas and oil heating systems, the ash in
a pellet heating system must occasionally be removed
from the collection container. In the case of pellet
stoves to be installed in the living room, fuel is manually
refilled into a storage container, which is then automatically
transported into the combustion chamber.
There are also special pellet stoves that can deliver up
to four-fifths of their heat to a central heating system
via a water bag.
Wood pellet heating: Pellets can be stored in aboveground or
underground tanks. The fuel feed to the heater works automatically.
Possible applications and benefits for municipalities:
Woodchips and pellets are locally produced energy
sources that are easy to store and, therefore, not only
reduce emissions but also increase value creation at a
local level. These are used for electricity and heat generation:
• Generation of electricity and heat from wood chips in
cogeneration plants, e.g. for schools or community
• Generation of district heating with woodchips (if
possible, in cogeneration)
• Operation of central heating systems and stoves with
Woodchips are often produced in mobile chipping
plants directly in forested areas or during landscape
maintenance work. Production from untreated waste
wood is also possible. Wood chips are typically used
for larger heating and cogeneration plants up to the
three-digit megawatt range, as they are more cost-effective
than wood pellets. Compared to wood pellets,
however, they require about three times as much storage
space for the same heating value.
In wood chip systems, the fuel and air supply are also
automatically regulated according to energy demand.
Here, the hot flue gases from the furnace also heat the
water in the boiler first. In order to generate electricity,
steam is produced from this, which is used to drive a
turbine. The residual heat left over after the turbine can
be used for heating (combined heat and power). When
only being used for heat, the boiler transfers the heat
directly to the heating circuit or storage unit.
22 | BIOENERGY
Biogas – stored solar energy to gas
Biogas is produced by fermenting energy crops, slurry, biological waste or similar materials in a fermenter. It
primarily consists of methane and can be used in a similarly flexible way as natural gas – for cooking, heating,
electricity generation and even as a fuel.
Biogas is produced by fermentation from organic
substances, from slurry to grass and biogenic waste. If
local waste materials are used for its production, such
as from agriculture or the food and catering industries,
the added value increases at a local level. Biogas consists
mainly of methane, i.e. the substance that is also
the primary component of natural gas, and is similarly
This means that conventional gas-fired power plants,
natural gas-driven cars, heavy goods vehicles or even
ships can also be run on biogas.
One particular advantage of biogas in the course of the
energy transition is its storability. It can effectively
help balance the fluctuating generation of wind and
solar power in the system.
Often, the biogas is used to run local cogeneration
plants – standardised mini power plants that supply
electricity and heat at the same time. This ensures a
particularly efficient use of the energy. Biogas can also
be used for cooking, heating and even as a fuel source
for specially adapted vehicles. What’s more, it is possible
to process biogas into pure methane. This can then
be used in exactly the same way as natural gas and can
also be fed into the natural gas grid and extracted again
For farms, the technology offers yet another advantage:
The fermentation residues from the fermenter possess
even better properties as fertiliser when compared to
the starting material.
BIOENERGY | 23
Functional principle and design
In the fermenter of a biogas plant, microorganisms
produce methane from biogenic materials, called “substrates”
(e.g. maize, rape, straw, slurry or food waste).
Depending on the climate zone, it may be necessary to
heat the fermenter to around 40°C (e.g. with the waste
heat generated during gas utilisation) so that the microorganisms
can work in an optimal way.
Possible applications and benefits for municipalities:
Biogas is a very versatile energy source that can be used
in a similar way to natural gas and not only reduces
CO 2 emissions but also increases local added value:
The gas produced is collected in a gas storage tank. In
addition to the main component of methane (50 to 70
per cent), it also contains other substances whose proportions
vary depending on the substrate in use. Carbon
dioxide (CO 2 ) is the second-largest component of
biogas, accounting for 35 to 50 per cent. The rest is primarily
nitrogen, water, oxygen and hydrogen sulphide.
• Local generation of electricity and heat in cogeneration
plants (e.g. for operating a dairy with gas
production from cattle manure)
• Use of biomethane for cars, heavy goods vehicles
• Replacement of natural gas with biomethane, e.g. in
heating systems or power plants
• Flexible power generation to compensate for
fluctuating wind and solar power output
Sulphur and water must be removed in a purification
plant. Then the biogas can be used, for example, in
cogeneration plants or vehicles that have been adapted
to use biogas.
An alternative way is to process the gas into biomethane
in a further purification step. The biomethane can be
used like natural gas in conventional heating systems,
engines and power plants. If it is to be fed into a
natural gas network, the last step is to fine-tune it so
that all the properties – such as its heating value and
dryness – match exactly.
In addition to biogas plants with automatic agitators
and pumps for filling and emptying, there are also very
simple and small models available. These are mostly
used in remote regions. They consist of a simple
container that is filled by hand. These are heated by the
sun. The gas is used, for example, in simple cookers as
an alternative to wood or dung.
Biogas plant with local heating network
24 PROJECT OVERVIEW
On the following pages, 20 exemplary projects from different regions that use renewable energy solutions are
presented. These projects demonstrate that the Energy Transition is delivering very practical benefits for people
and communities, which are reflected in lower energy costs and greater security of supply, among others.
PROJECT OVERVIEW |
Renewable Solution/Technology Location Page
1. Photovoltaics, wind power . . . Nart Töv, Mongolia . . . . . . . . . . . . . . . . . . . . . . . 26
2. Photovoltaics . . . . . . . . . . Kachanovichi, Belarus . . . . . . . . . . . . . . . . . . . . . 27
3. Photovoltaics . . . . . . . . . . Duisburg, Germany . . . . . . . . . . . . . . . . . . . . . . . 28
4. Photovoltaics . . . . . . . . . . Bishkek, Kyrgyzstan . . . . . . . . . . . . . . . . . . . . . . 29
5. Photovoltaics . . . . . . . . . . Mongun-Taiga, Republic of Tuva, Russian Federation. . . . . . 30
6. Photovoltaics . . . . . . . . . . Tashkent, Uzbekistan. . . . . . . . . . . . . . . . . . . . . . 31
7. Solar thermal . . . . . . . . . . Chemnitz, Germany . . . . . . . . . . . . . . . . . . . . . . 32
8. Solar thermal, biomass . . . . . Zwiesel, Germany. . . . . . . . . . . . . . . . . . . . . . . . 33
9. Hydropower . . . . . . . . . . .
Republic of Kabardino-Balkaria, Russian Federation . . . . . . 34
10. Hydropower . . . . . . . . . . . Himmelpforten, Germany. . . . . . . . . . . . . . . . . . . . 35
11. Geothermal, photovoltaics. . . . Grodno, Belarus . . . . . . . . . . . . . . . . . . . . . . . . 36
12. Geothermal . . . . . . . . . . . Vershinino, Russia . . . . . . . . . . . . . . . . . . . . . . . 37
13. Geothermal . . . . . . . . . . . Zhitkovo, Russia . . . . . . . . . . . . . . . . . . . . . . . . 38
14. Wind power . . . . . . . . . . . Ulyanovsk, Russia . . . . . . . . . . . . . . . . . . . . . . . 39
15. Wind power . . . . . . . . . . . Barwice, Poland. . . . . . . . . . . . . . . . . . . . . . . . . 40
16. Biomass . . . . . . . . . . . . . Kalinkovichi, Belarus . . . . . . . . . . . . . . . . . . . . . . 41
17. Biomass . . . . . . . . . . . . . Kobryn, Belarus . . . . . . . . . . . . . . . . . . . . . . . . 42
18. Biogas. . . . . . . . . . . . . . Forst, Germany . . . . . . . . . . . . . . . . . . . . . . . . . 43
19. Biogas, wind power, biomass . . Feldheim, Germany . . . . . . . . . . . . . . . . . . . . . . . 44
20. Hydropower . . . . . . . . . . Gudauri, Georgia . . . . . . . . . . . . . . . . . . . . . . . . 45
26 | EXAMPLE PROJECTS
Mongolia: Hybrid plant supplies electricity for rural training center
The photovoltaic-wind energy hybrid system supplies the MULS field office with electricity.
About 140 kilometres from the capital Ulaanbaater, in
Nart Töv, lies the training centre of the Mongolian University
of Life Sciences. Until a few years ago, a diesel
generator produced electricity there for lighting, small
electrical appliances and for the pumping of drinking
water. Noise and exhaust pollution was a standard feature.
That changed in 2015 thanks to HEOS Energy. The
company built a photovoltaic-wind energy hybrid system
for the rural branch of the university, which makes
living, learning and working on campus much easier.
A small wind turbine with 15 kilowatts of power generates
37,000 kilowatt hours of electricity per year, while
the photovoltaic system – with 6.44 kilowatts of power
– supplies 11,500 kilowatt hours of solar electricity. The
electricity can be temporarily stored in leadgel batteries.
An emergency generator secures the energy supply
if the power from the other energy generators and the
storage unit is not sufficient.
Encouraged and inspired by the quiet and emission-free
power generation now available, the operators immediately
added the new greenhouse and workshops.
After commissioning, HEOS trained both teachers and
students on how the off-grid hybrid system works and
how to maintain it.
The hybrid plant was built as part of the Renewable
Energy Solutions Programme of the German Energy
Agency (dena) of which is part of the “Energy Export
Initiative” of the Federal Ministry for Economic Affairs
With information and practical experiments on the topics of
photovoltaics and wind energy, HEOS Managing Director, Dr.
Klaus Hoffmann, added variety in the curriculum for the students
EXAMPLE PROJECTS |
Belarus: Solar power plant secures power supply
Photovoltaic power plant with 1.6 megawatt capacity.
In the Nesvizhskyi district, located in the region of
Minsk, a photovoltaic power plant known as “Kachanovichi”
with a capacity of almost 1.6 megawatts has
been generating electricity for agriculture, industry and
residential buildings since July 2020.
The open-air plant is located on a five-hectare site near
the village of Kachanovichi. Every year, 4,752 photovoltaic
modules feed around 1,501,000 kilowatt hours into
the power grid of the energy provider Minskenergo.
In the rural region, farms, in particular, need a lot of
electricity for grain drying during harvest time. This
fits in well with solar power generation: In summer,
the photovoltaic system generates the majority of the
energy because of the high levels of solar radiation.
The plant generates electricity for agriculture, industry and
The industrial companies in the region also have a high
demand for electricity. The decentralised power plant
supports the power supply of industry and around 1,000
Furthermore, the plant reduces fuel consumption by
about 500 tonnes per year and thus reduces CO 2 emissions.
The proximity to the consumers also reduces the
transport costs for the provision of energy.
The owner of the solar power plant is CJSC REAG Nesvizh,
and the undertaking was realised by the project
company ALC ENECA.
The 4,752 photovoltaic modules feed around 1,501,000 kilowatt
hours into the power grid of the energy supplier Minskenergo
28 | EXAMPLE PROJECTS
Germany: Cheap solar power for tenants
In municipal housing, service charges for the provision
of energy for tenants are also an issue. The lower the
additional expenses, the easier it is for people with low
incomes to shoulder the financial burden. One area of
potential adjustment is energy supply. The Duisburg-
Süd housing cooperative in the Ruhr region shows a
way for tenants to save with solar power.
The specialist company Solarimo has installed photovoltaic
modules with a total output of 240 kilowatts on
several roofs of a residential complex. In this way, the
housing company avoids 130 tonnes of carbon dioxide
every year and contributes to climate protection.
One of the photovoltaic systems, which has an output
of 100 kilowatts, has been producing electrical energy
for almost 70 tenants since October 2019. Residents
have the option of purchasing the CO 2 -free electricity
at a price that is 20 per cent lower than that of the
external energy supplier. When the sun is not shining
sufficiently, they receive energy from German hydropower
plants. Electricity is sold through Solarimo.
Photovoltaic system with a total output of 240 kilowatts on
several roofs of the residential complex.
After the positive experience enjoyed with the pilot
plant, the housing cooperative decided to launch three
more tenant electricity projects.
EXAMPLE PROJECTS |
Kyrgyzstan: Solar power for a children’s home
Since mid-2015, a photovoltaic system has been generating
solar power for the children’s home in the capital
Bishkek. Around 100 boys and girls live in the “Rehabilitation
Center for Homeless Children”. They benefit
from the energy costs saved by solar power. Numerous
groups of visitors have already learned about energy
generation with the help of the photovoltaic system,
including company representatives, students and
With a module area of 101 square metres, the system
has an installed capacity of 16.38 kilowatts. It produces
approximately 222,500 kilowatt hours of electricity per
year. In summer, the photovoltaic system covers the
children’s home’s monthly demand of 1,800 kilowatt
hours. In winter, as well as throughout the year, it
keeps the power supply stable. The solar power avoids
carbon dioxide emissions of around 7,430 kilograms
After preparation together with Kyrgyz partners, R.I.D.
GmbH installed the plant. It was built as part of the
Renewable Energy Solutions Programme of the German
Energy Agency (dena) of which is part of the “Energy
Export Initiative” of the Federal Ministry for Economic
Affairs and Energy.
Training on installation, maintenance and service took place
both in Bishkek and in Germany directly at the company R.I.D.
30 | EXAMPLE PROJECTS
Tuva: Solar diesel hybrid system for remote villages
The autonomous photovoltaic-diesel hybrid system reliably supplies 7,000 residents with electrical energy.
A stable power supply improves living conditions in remote
villages, while solar energy reduces the consumption
of diesel fuel by generators. For these reasons,
the government of the Republic of Tuva decided to use
an autonomous photovoltaic-diesel hybrid system to
supply electricity to two villages in the Mongun-Taiga
The Hevel Group installed solar power systems with a
total output of 550 kilowatts, battery systems with 710
kilowatt hours (kWh) of storage capacity, and diesel
generators. They reliably supply the 7,000 inhabitants
of the villages of Mugur-Aksy and Kyzyl-Khaya with
electrical energy around the clock.
The facilities went into operation in December 2019. In
2020, the Hevel group reported that the solar modules
generated over 750,000 kWh of electricity. One of the
two villages supplies itself exclusively with solar power
during the day, even in winter. The fuel requirement
for diesel generators has been reduced by 30 per cent,
thereby saving approximately 408 tonnes of CO 2 each
The Hevel Group implemented the project with its own
financial resources within the framework of an energy
service contract. The electricity price for consumers
has remained stable. In the long-term, this model will
allow the region to reduce the subsidised cost of diesel
Solar power plant with an output of 550 kilowatts.
EXAMPLE PROJECTS |
Uzbekistan: Tashkent University uses solar power
The plant demonstrates the opportunities and perspectives of solar power generation and storage
The photovoltaic system, which was installed in 2016 on
the grounds of the Tashkent State Technical University
“Abu Rayhan Beruni”, fulfils multiple goals at once. It
demonstrates the opportunities and perspectives of solar
power generation and storage in Uzbekis tan. Due to its
highly frequented location, it has aroused significant
public interest. It also offers students the opportunity to
deepen their knowledge on the subject of solar energy
through the demonstration object.
Technically, the photovoltaic system, which is elevated
on a flat roof, has two special features. On the one
hand, solar modules with the innovative PERC technology
have been installed. The modules from the German
manufacturer Meyer Burger achieve an above-average
efficiency of over 20 per cent. Secondly, the plant is
coupled to an energy storage system with battery cells
from BAE Batteries.
With an output of 17.4 kilowatts, the photovoltaic system
produces around 267,200 kilowatt hours of solar
electricity every year. This saves about 17,370 kilograms
of carbon dioxide.
The reference plant is a project of BAE Batteries and
Pretherm Solutions. It was built as part of the Renewable
Energy Solutions Programme of the German
Energy Agency (dena) of which is part of the “Energy
Export Initiative” of the Federal Ministry for Economic
Affairs and Energy.
32 | EXAMPLE PROJECTS
Germany: Plenty of solar heat for apartment buildings
The solar thermal system supplies emission-free energy for room heating and hot water production.
In Chemnitz, Germany, the construction company FASA
AG has demonstrated for many years that solar thermal
systems can cover large parts of the energy demand for
space heating and hot water in buildings in a regenerative
and emission-free way. This reduces heating costs
for the residents and increases the value of the properties.
The current construction project “Solardomizil” is
a lighthouse project for both multi-storey residential
construction and solar heating.
2,317 square metres of solar collectors cover half of the heating
needs for 29 flats.
In the first construction phase with two condominium
complexes (Solardomizil I+II), 317 square metres of
solar collectors will generate enough to meet half of the
heat demand for 29 apartments. In the third construction
phase, which will feature an optimal southern
alignment of the system, FASA will even achieve 60 per
cent solar heat share for the 24 apartments.
FASA set up long-term heat storage tanks with 200
cubic metres of water for the intermediate storage of
the solar heat. These steel tanks extend over several
floors. The additional costs for the solar thermal
systems amount to about ten per cent, but they are
impressive proof that the construction company and
the municipality are committed to a sustainable energy
supply with the help of solar energy.
EXAMPLE PROJECTS |
Germany: Solar heat network of old and new buildings
Two solar thermal systems with a total of 76 square metres of collectors provide heat for the parish centre and the residential building.
In Zwiesel, Bavaria, Germany, planners have come up
with a smart concept to supply an old building and a new
building in a heating network with two solar thermal
systems. The parish owns two buildings; the parish
house had already seen extensive thermal renovation
work in 2006. In 2010, the parish built a modern,
energy- saving building in place of the old parish centre
next door. It houses a lecture room, additional group
rooms, a kitchen and sanitary facilities. Previously, the
200-kilowatt boiler had consumed 25,000 litres of oil a
year; the new parish centre is heated exclusively with
solar heat and wood. The 60-kilowatt pellet boiler only
heats when the sun’s energy is not sufficient.
The solar thermal systems cover 60 per cent of the heat demand
in the parish centre – emission-free.
For this purpose, 36 square metres of solar collectors
were mounted on the southeast façade, plus a further
40 square metres of free-standing solar thermal collectors
located beside the main buildings. The systems
cover 60 per cent of the heat demand in the new parish
centre, which shares solar heat with the five-storey
parish residence. The control system ensures that the
solar heat is utilised optimally. As a result, both buildings
are able to cover about 40 per cent of their heating
needs emission-free from the solar systems.
The project was planned and realised by, among others,
the architectural office Löw and the engineering office
Hilz from the Bavarian town of Zwiesel, as well as the
building services company Wölf in the municipality of
The solar heat is optimally distributed to both buildings.
34 | EXAMPLE PROJECTS
Kabardino-Balkaria: Small hydropower plant with secure returns
The small hydropower plant on the Cherek River produces 60 gigawatt hours of electricity per year.
With its mountains and mountain rivers, the North
Caucasus has ideal geographical conditions for the use
of hydropower. In the Republic of Kabardino-Balkaria
alone, plants with 198.1 megawatts of capacity are in
operation. Of these, 73 megawatts belong to the socalled
small hydropower. Last year, the power company
and hydropower plant operator RusHydro commissioned
a small hydropower plant with a capacity delivery
contract (DPM in Russian) for renewable energy in
Verkhnebalkarskaya. The agreement ensures a guaranteed
return for the operators.
The three turbines and generators boast a combined output of
With three Voith turbines and three generators with a
total output of ten megawatts, the run-of-river power
plant on the Cherek mountain river produces around
60 gigawatt hours of electricity per year. The plant
helps to secure the electricity supply in the republic and
reduces dependence on electricity supplies from other
regions. With pollution-free electricity generation, it
has minimal impact on the environment. Furthermore,
a stable energy supply promotes the settlement and
expansion of businesses in the mountain region, thus
securing and creating jobs. This, in turn, leads to stable
tax payments in the municipalities.
Electricity from hydropower contributes to a stable energy
EXAMPLE PROJECTS |
Germany: Modernisation of a small hydropower plant
The hydroelectric power plant on the Möhne River has been in operation since 1906 and today produces 2.2 million kilowatt hours of
generation from hydropower
has a centuries-old
That is why many hydropower
plants have been in
operation for decades.
When the time comes for
modernisation, it is
advisable to also improve
the protection of fish and
water bodies. This was
also the case with the plant in Himmelpforten in North
Several measures also improved the level of environmental
friendliness and conditions for fish stocks. For
example, the rake distances were reduced so that the
fish do not swim into the turbines. They reach their
spawning grounds via a new device known colloquially
as a “fish ladder”.
In 1906, the diversion power plant in the river Möhne
was put into operation for the first time. It has been
generating electricity with two turbines ever since.
After more than 100 years of operation, the hydropower
plant was to be modernised. A Kaplan tubular turbine
with 600 kilowatts of power was installed, which went
into operation at the beginning of 2012. The highly
efficient plant generates around 2.2 million kilowatt
hours of electricity per year. That is a third more than
The new Kaplan tubular turbine with 600 kilowatts of power.
before and enough for 624 households. The annual CO 2
avoidance amounts to 900 tonnes.
36 | EXAMPLE PROJECTS
Belarus: Heat from the earth, electricity from the sun
Heat pumps supply energy for heating and hot water. Photovoltaic modules are installed on the façade and provide clean electricity.
In Grodno, in the far west of Belarus, a ten-storey residential
building with a special form of energy supply
was built in 2017. Three geothermal heat pumps with
a total output of 136 kilowatts provide heat for heating
and hot water. Underfloor heating distributes the heat
in the 120 flats.
Part of the total of 300 photovoltaic modules is installed on the
While the load-bearing walls are made of bricks, the
outer walls are made of aerated concrete blocks, which
provide better thermal insulation. The rooms are
equipped with automatic ventilation systems. Heat is
recovered from the exhaust air and waste water via heat
exchangers, thus pre-heating the fresh air and water
respectively before they enter the building.
A total of almost 300 photovoltaic modules are installed
on the roof and façade. They generate 64,000 kilowatt
hours of climate-friendly solar electricity annually,
which is sold to the local grid operator. An information
screen in the building shows – in real time – how much
energy is currently being generated and consumed in
The house in Grodno is part of a project funded through
the UNDP Global Environmental Finance (UNDP-GEF)
programme to increase energy efficiency in new buildings,
which also includes buildings in Minsk and
EXAMPLE PROJECTS |
Russia: Secondary school heats its buildings with geothermal heatpumps
The village school uses geothermal energy for heating and hot water supply.
The newly built village school of Vershinino in the
Tomsk region of Siberia has been heated and supplied
with hot water by geothermal heat pumps since 2014.
With the help of 28-vertical geothermal probes that
reach down approximately 50 metres, the plant extracts
heat from the ground. Two heat pumps raise the
low temperature level from the ground to 55 degrees
Celsius so that the energy can be used for heating and
hot water production. The temperature can be increased
up to 100 °C if necessary. Together, the two heat pumps
provide a heating output of 84 kilowatts. To generate
four kilowatt hours of heating, only one kilowatt hour
of electrical energy needs to be used. The 1,454 square
metre school building is heated via underfloor heating
combined with room thermostats. The entire system
was implemented by Ecoklimat, a Siberian company
specialising in heat pump heating systems.
The 28-vertical geothermal probes reach down into the earth
approximately 50 metres.
If the school were heated with fossil fuels, 19 tonnes
of natural gas or 25 tonnes of diesel would be needed
annually. The modern heating technology pays for itself
within a few years and ensures a high degree of independence
from fossil fuels.
The two heat pumps with a heating capacity of 84 kilowatts.
38 | EXAMPLE PROJECTS
Russia: School cuts heating costs to a quarter with geothermal energy
The school in Zhitkovo can reduce heating costs by around 75 per cent with the help of heat pumps.
The secondary school inZhitkovo in Leningrad Oblast
has been heated with geothermal heat pumps since the
end of 2020. Previously, an electric convection heating
system provided heat in the brick building from 1965
with 1,150 square metres of heated room space. The
energy costs were 3 to 3.5 million roubles annually. According
to calculations, the new heating system should
reduce costs by 75 per cent. The investment in the new
heating system will thus pay for itself in just six years.
Three heat pumps are installed in the new boiler room,
which together can provide 91 kilowatts of heating
power. In addition, there is an electric boiler with 21
kilowatts of power and a 1,000-litre buffer tank. The
electrically driven heat pumps extract energy from
14 geothermal probes that reach 145 metres into the
ground. The temperatures in the ground are +5 to
+10°C, even in winter. In the building, the heat is
distributed via new low-temperature radiators with
The “Centre for Energy Saving and the Improvement
of Energy Efficiency of the Leningrad Administrative
District” included the school in the list of “demonstration
sites with high energy efficiency”. Students from
the educational institutions of the Leningrad Administrative
District visit the building to learn about energyefficient
technologies. In addition, representatives of
interested companies and organisations can learn about
the technologies used in order to implement further
The three heat pumps extract energy from the ground at a
depth of 145 metres.
EXAMPLE PROJECTS |
Russia: Wind farm strengthens research and creates jobs
“Ulyanovsk 1”: Russia’s first commercial wind farm with 28 wind turbines and a total capacity of 35 megawatts.
In 2018 and 2019, Russia’s first commercial wind farm
was built in Ulyanovsk on the banks of the Volga River:
“Ulyanovsk 1”. It consists of 28 turbines with a total
capacity of 35 megawatts and supplies 8 per cent of the
region’s electricity. At the local Ulyanovsk State Technical
University, where courses in renewable energies
are now also offered, it serves as a demonstration and
The wind farm was initiated by the Finnish energy
company Fortum and the Russian Direct Investment
Fund (RDIF). Fortum is also developing further wind
and solar power plants in Russia. The Danish company
Vestas not only supplied part of the wind turbines, but
is also setting up a manufacturing facility for rotor
blades in the city – creating new local jobs in wind
power. One other pleasing effect: Since the wind
turbines have dominated the skyline of Ulyanovsk, the
wind farm has also become the Instagram hotspot in
the area. In the meantime, many more wind farms have
been built in the region and more are to follow.
40 | EXAMPLE PROJECTS
Poland: Wind power replaces lignite
The Barwice wind farm generates 112 gigawatt hours of electricity per year, enough for 27,000 four-person households.
Since April 2020, 14 wind turbines have been turning at
the Barwice wind farm near the town by the same name
in north-western Poland, each with a rotor diameter
of 113 metres and an output of 3 megawatts. Together,
they generate 112 gigawatt hours of electricity a year –
enough to supply 27,000 four-person households and
avoid around 48,000 tonnes of CO 2 emissions annually.
Wirtgen Invest Energy implemented this project, and
the turbines are from Siemens Gamesa. To date, 70 per
cent of electricity in Poland comes from lignite, which
leads to particularly high CO 2 emissions. Poland has a
high potential for onshore and offshore wind energy.
After stagnation in recent years, a total of 3.5 gigawatts
of wind power capacity was awarded in a tender process
in 2018 and 2019. The production of wind turbines
and components has developed into a great economic
realisation in Poland with a turnover of several hundred
million euros. Siemens Gamesa alone employs more
than 200 people in Poland.
EXAMPLE PROJECTS |
Belarus: Electricity and district heating from woodchip
The plant has reduced heat generation costs by 20 per cent by using wood chips.
The short-rotation plantation (SRP) Kommunalnik
Kalinkowitschskiy has been using woodchips to generate
district heating and electricity in the small town
of Kalinkowitschi in the south of Belarus since 2018. In
total, the local heating plant provides 56.5 megawatts
of district heating capacity. Of this, 10 megawatts come
from a woodchip boiler from the Lithuanian manufacturer
Enerstena. In addition, three natural gas boilers
are used for hot water. Another woodchip boiler
with 6.5 megawatts of thermal output was combined
with a turbo generator from Siemens to form what is
known as cogeneration or combined heat and power
(CHP), which now supplies 1.39 megawatts of electrical
output. In this way, it was possible to reduce heat
generation costs by 20 per cent. The heating plant has
created jobs for 30 people. CO 2 emissions are expected
to fall by 368,000 tonnes over the life of the plant. The
project was financed with the help of USD 14.17 million
from the International Bank for Reconstruction and
The CHP plant recovers thermal energy to achieve great
42 | EXAMPLE PROJECTS
Belarus: Wood-fired heating plant reduces district heating costs
The wood chips are stored behind the boiler house.
In Kobrin, a town of 50,000 inhabitants in the southwest
of Belarus, Kobrinskoe ZhKH (which means
housing and communal services) commissioned a new
boiler house in 2019, which is fired with wood chips.
It reduces dependence on imported natural gas and
increases local value creation. The three boilers, each
with a peak output of four megawatts, were manufactured
by the Belarusian-French company JLLC Komkont
based in Gomel. Kobrinskoe ZhKH also operates its own
wood chip production and logistics. The bottom line is
that the new plant reduces the costs for district heating
by around 40 per cent.
The use of wood chips in the new boiler house reduces energy
production costs by 40 per cent.
The modern wood-fired heating centre is equipped
with an automatic fuel supply and automated control
technology, and the boilers have an efficiency of 91 per
cent. During the heating season, the new boiler house
operates in parallel with an existing gas boiler plant;
in the warmer season, the gas boilers are switched off.
According to calculations, the new boiler house saves
14 million cubic metres of natural gas annually and will
thus reduce CO 2 emissions by 449,000 tonnes over its
Boiler with a peak output of four megawatts and an efficiency
of 91 per cent.
The new construction of the boiler house in Kobrin is
part of the project entitled “Use of wood biomass for
district heating” funded by the International Bank for
Reconstruction and Development, which includes a
total of 20 boiler houses.
EXAMPLE PROJECTS |
Germany: Electricity, gas and heat from chicken manure and energy crops
The biogas plant supplies 60 gigawatt hours of energy annually, enough to heat 4,000 homes.
In the small town of Forst in Lusatia, a region in
eastern Germany dominated by lignite, the company
“Bioenergiepark Forst GmbH & Co. KG” has been feeding
biomethane into the natural gas grid of the local
operator Ontras VNG since 2014. The biogas is obtained
from the fermentation of poultry manure and renewable
The treatment plant has a capacity of 700 standard cubic
metres per hour. Each year, it supplies biomethane with
an energy content of 60 gigawatt hours – enough to
heat 4,000 homes.
The plant uses a special gas treatment process named
EnviTec Biogas AG, after the company that designed it.
The hollow fibre membranes used enable a gas purity of
96 per cent methane. The arrange ment of the membranes
in a horizontal cartridge system within the plant
ensures that twice as much biogas can be purified in
the same space as with conventional processes.
The special gas treatment process enables a gas purity of 96 per
In addition to the processing plant, the biogas is also
used to operate a combined heat and power plant,
which has an electrical output of 549 kilowatts.
Chicken manure and renewable raw materials ferment in the
fermenters, thereby producing gas.
44 | EXAMPLE PROJECTS
Germany: “Bioenergy village” Feldheim supplies itself with wind, sun and biogas
55 wind turbines supply most of the village’s electricity, 250 gigawatt hours per year
The lion’s share of the electricity, 250 gigawatt hours
per year, is supplied by the 55 wind turbines. In
addition, there are 2.75 gigawatt hours of solar power,
which come from 284 decentralised photovoltaic
systems. Together with a lithium-ion battery with a
capacity of 10.7 megawatt hours, this becomes an intelligent
A combined heat and power plant with 0.5 megawatts of
electrical power generates electricity and heat from biogas.
The approximately 130 inhabitants of the village of
Feldheim, southwest of Berlin, have taken the topic
of energy supply into their own hands: Since 2010,
they have been supplying themselves with electricity
and heat from renewable energies. 90 per cent of the
houses are connected to the local heating network. The
customers are also shareholders of Feldheim Energie
GmbH & Co KG. They now save 31 per cent on electricity
and 10 per cent on heating costs and can rely on stable
prices. Local businesses benefit from the construction
and operation of the facilities. The project attracts
interested parties and is part of collaborative research
efforts with universities.
In addition, a combined heat and power plant with
0.5 megawatts of electrical output provides 4 gigawatt
hours of electricity and 2.2 gigawatt hours of heat for
the local heating network per year. It is operated with
biogas from maize silage and liquid manure, while the
fermentation residues serve as fertiliser. In winter,
a woodchip plant provides additional heat. Feldheim
has received a grant from the EU for the local heating
network. In total, the bioenergy village avoids around
170,000 tonnes of CO 2 emissions per year.
EXAMPLE PROJECTS |
Georgia: Small hydropower helps to support tourism
The Aragvi II small hydropower plant blends inconspicuously into Georgian nature.
In Georgia, hydropower plays an important role in
securing a reliable energy supply and reducing dependence
on fossil fuels. In the north-east of Georgia, the
Aragvi II small hydropower plant supports the electricity
supply of the emerging ski and tourism region of
Gudauri. For small and large hydropower projects, it is
particularly important to assess and consider the environmental
impacts before, during and after completion.
For the Aragvi II project, it was particularly important
that the power plant did not disturb the natural environment.
The power plant, which includes the operator’s
office, the primary machinery and the turbine, is
designed to blend into the mountain landscape. The 2
MW horizontal Francis turbine provided by Voith Hydro
generates approximately 13 GWh per year, depending on
the season, and was commissioned in early 2019. With
many years of experience, Voith Hydro is one of the
leading industrial partners for the planning, construction,
maintenance and modernisation of hydropower
plants in the region.
With an output of three megawatts, the turbine generates
around 13 gigawatt hours of electricity per year.
Hydropower ensures a reliable energy supply and thus promotes
tourism in Georgia.
46 | CONTACT INFORMATION
Further contact information
German Economic Information Centre in Belarus
220116 Minsk, Gazeta Pravda Avenue 11A +375 17 378 81 41
Информационный центр немецкой экономики
220116 г. Минск, Проспект Газеты «Правда» 11A https://belarus.ahk.de
Representative Office of German Business in Belarus
220116 Minsk, Gazeta Pravda Avenue 11A +375 17 2554324
Представительство немецкой экономики в Республике Беларусь
220116 г. Минск, Проспект Газеты «Правда» 11 https://belarus.ahk.de
Association of Renewable Energy of Kazakhstan
010000 Nur-Sultan, Yanushkevich St. 1 +7 (701) 710-89-15
Ассоциация возобновляемой энергетики Казахстана (АВЭК)
010000 г. Нур-Султан, ул. Янушкевича 1 kazrenergy.com
Solar Power Association of Kazakhstan
010000 Nur-Sultan, distr. Chubary, Alexander Knyaginin St. 11 +7 701 286 69 50
ОЮЛ «Казахстанская ассоциация солнечной энергетики»
010000 г. Нур-Cултан, мкр. Чубары, ул. Александра Княгинина, д. 11 https://spaq.kz/rus/
Delegation of German Business for Central Asia
Kazakhstan, 050040 Almaty, Business center «Koktem Square»,
Bostandykski rayon, mdistr. Koktem 1, 15 a
Представительство германской экономики в Центральной Азии +7 727 356 10-61 bis -66
Казахстан, 050040 г. Алматы, Бизнес-центр «Koktem Square»,
Бостандыкский район, мкр. Коктем 1, 15 a
CONTACT INFORMATION |
Russian Association of Wind Power Industry +7 495 134 68 88
197706 St. Petersburg, Tokareva St. 8/12 +7 981 980 0846 whatsap
197706 г. Санкт-Петербург, ул. Токарева, 8/12 www.rawi.ru
Distributed Power Generation Association
125167 Moscow, Victorenko St. 5, building 1, BC «Victory Plaza»
Ассоциация малой энергетики +7 351 247 33 99
125167 г. Москва, ул. Викторенко, 5, firstname.lastname@example.org
строение 1, БЦ «Victory Plaza»
Photovoltaic Industry Association
Ассоциация предприятий солнечной энергетики
Russia Renewable Energy Development Association
123610 Moscow, Krasnopresnenskaya embankment 12, entrance 6 +7 (495) 115-10-34
Ассоциация развития возобновляемой энергетики (АРВЭ)
123610 г. Москва, Краснопресненская набережная, д. 12, подъезд 6 https://rreda.ru/
119334 Moscow, Leninsky prospekt 38A
Некоммерческое партнерство по Раазвитию Возобновляемых +7 985 760-8010
источников энергии ЕВРОСОЛАР Русская секция
119334 г. Москва, Ленинский проспект, д. 38А http://www.eurosolarrussia.org/
German-Russian Chamber of Commerce Abroad
121087 Moscow, Business-Center Fili Grad,
Beregovoy Proezd 5A, building 1
Российско-Германская внешнеторговая палата +7 495 234 49 50
121087 r. Москва, Бизнес-центр «Фили Град», email@example.com
Береговой проезд, д. 5А, к.1