CTO Assessment - European Commission

KRONSBERG
an innovative
building area
Contact: Rheinhard Martinsen
Responsible coordinator for environmental planning • Germany
Tel: +49 511 168.44466 • Email:Reinhard.Martinsen@hannover-stadt.de
Kronsberg is a district area of the German
city of Hannover where a demonstration
project of 6000 dwellings has been in the
process of establishment between the end
of the 90’s and 2003 Its aim is to show
how far one can go in promoting environmental
measures. This was part of ambitious
projects within the framework of the
World Expo in Hannover by 2000. The
objectives were to reduce the energy consumption
by 50% and CO 2
emissions by
60%. Once the project is finished, 15,000
inhabitants will live in a completely energy
sustainable district. Thanks to a long-tradition
of consultation when the City Council
takes decisions on public projects, all
main actors indirectly involved in the project
came to an agreement to have the most
environmentally-friendly measures possible
in the sector of energy use and energy
supply; water management; numerous
waste management strategies; soil management
and transport measures among
others, taking into account the economic
constraints.
The project
The city’s 30 year-long experience of consultation
with citizens to reach high levels
of public acceptance for any major public
project implemented that will influence the
environment and public space led to an ecological
showcase built for the World Exposition
hosted by Hannover in the year
2000. As the Kronsberg site was close to
the expo, one condition of the contract between
the city and other EXPO organizers
was the construction of the Kronsberg
Sustainable Residential Area.
The concerted approach in the case of
Kronsberg took place among the Council,
the environmental and consumers groups,
as well as with investors, architects and
housing companies. As a result of the action
plan, several measures were adopted
to promote the development of this project:
1) the ground was sold to the real estate
agents at the lowest possible market price;
2) long-term benefits of the investment were
demonstrated to the real estate agent; 3)
indirect subsidies were given to future
house owners, in order not to make the
price more expensive than if there had been
no environmental measures.
Concerning energy measures, the city
project installed two wind turbines of 1.5
and 1.8 MW, an optimised energy provision
by a differentiated district heating
system fed by two decentralised
cogeneration plants, developed the
“solarcity” solar power project with a
superinsulated 2,750 m 3 seasonal storage
tank and other innovative technology such
as passive houses, photovoltaic plants at
the primary school, etc...
Overall Evaluation
The project shows flexibility and adaptability
to always find the best environmental
option, taking into account the economic
constraints: for instance, if so far
the local district heating system is run by a
Combined Heat and Power system with
natural gas, being still the most economic
option, the project developers keep an eye
on replacing it with fuels cells, as soon as
they become economic.
Key facts of the project
Challenges
To overcome the costs barriers of the
project the Council offered indirect subsidies
to future inhabitants on one side, while
on the other side made the selling price of
the ground for house promoters about the
same than if there had been no environmental
measures. This was possible because
the city owned the ground. At the
same time, the price of the construction
area was still not below the minimum market
price of the ground. However house
promoter could be finally convinced when
told that despite initial investment costs
were high, the very low maintenance and
running costs enable a pay-back period of
7 years already.
A certain lack of knowledge of and therefore
lack of support for RES coming from the
population and even from architects, necessitated
to set up public information campaigns
as well as training courses for architects
and building companies to show not
only how to build such low-energy buildings,
but also the economic benefits, not to mention
the innovative side of such as project.
Replication Potential
The Expo opened the minds of local investors
and architects who wanted to be involved
in innovative projects. After the World Expo,
this movement continued, but was slightly
less active. The project was a concrete example
of how this can work. Now, the real estate
sector of the nearby area is sensitive. If
it offers lower quality construction, it may
gain a bad image, as the population expects
to have the same standards as the Kronsberg
buildings.
From the point of view of the main project
promoter this project that has been presented
to several other European countries as a
showcase is replicable. However, it is facilitated
if some event out of the ordinary takes
place at the local level: this will encourage
local authorities to push for innovative
projects.
Kronsberg: A whole new environmentally friendly district: 6,000 dwellings for
15,000 inhabitants
Reduce energy consumption by 50%
Reduce CO 2
emissions by 60%
Lesson lernt: One good example in your own city gives a new scale of
reference and encourages replication.
CTO - Showcase
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