European Green City Index - Siemens

European Green City Index | Lessons from the leaders
Buildings
When it comes to buildings, no city can start
from scratch: each has to work with the
legacy of generations. An unattributed quote,
meant for humorous effect, captures the problem
neatly: “Our problem is that the buildings
from 100 years ago were built to last 100 years;
the buildings of 50 years ago were built to last
50 years; and the buildings of 20 years ago were
built to last 20 years.”
This highlights one of the key difficulties in
reducing the environmental impact of buildings.
Take Berlin, the category co-leader: since 1990,
the reunified city has had to find ways to shift
the carbon requirements of a host of building
types towards a more sustainable level. One
obvious place to start is not with the buildings
themselves, but with the kind of energy powering
them.
The city’s heating modernisation programme,
for example, encouraged a substantial
shift in fuel source through grants, advice and
tighter regulation on new buildings. In 1990,
over 400,000 apartments still had coal furnaces;
by 2005, the number had dropped to just
60,000. Most of the shift was towards cleaner,
although still carbon releasing, natural gas.
While improving the energy mix, Berlin has
also attempted to address the deficiencies of
some of its buildings. It has not been so much a
case of making do with existing infrastructure,
but rather improving to make it greener. An
“Energy Saving Partnership”, for example, has
private companies improving the energy efficiency
of public buildings with both the contractors
and the city benefiting from the cost savings.
So far, the scheme has led to €60 million in
private investment, saved the city €2.4 million in
costs, and brought carbon emissions down by
600,000 tonnes.
An even bigger effect has come from the
city’s efforts to improve what local experts call
the once “ramshackle” flats built of prefabricated
concrete under the previous East German
regime. Of the 273,000 apartments, the city has
fully refurbished about two-thirds of them, and
partially upgraded the other 35%, at an average
cost of €20,000.
Not all of this goes to better energy efficiency.
It is a broad-ranging programme to increase
the attractiveness of these properties: about 5%
of spending, for example, goes on the surroundings.
Energy efficiency is, however, an important
consideration.
According to Peter Woll schläger of the Berlin
Senate Department of Urban Development, the
city has found that the optimal, cost-effective
measures for saving heat energy are insulation
of the outer walls and top floor ceiling; new airtight
windows; and renovation of the building’s
heating system. These three measures reduce
annual carbon emissions by between 1 and 1.4
tonnes per flat.
However, Mr Wollschläger points out that
even over the long term the energy savings do
not pay the entire cost of the refurbishment of
these flats. The benefits extend beyond energy
savings, however, such as lower maintenance
costs for these flats given that the improvements
reduce mould and mildew, as well as
keeping temperatures more even. Quite simply,
they are nicer places to live.
The lessons which the city has learned could
have a substantial impact worldwide. Across
central and eastern Europe, the city estimates
that there are nearly 50 million flats of similar
construction, and in China there are about 200
million.
Between 2005 and 2007, through the Baltic
Energy Efficiency Network for Building Stock
(BEEN), Berlin shared its knowledge with cities
in Poland and the Baltic states and worked with
them on understanding how best to finance
such renovation. Now the EU is funding the Urb
Energy project to take things further, looking not
just at individual buildings but at urban infrastructure
and holistic rehabilitation of whole
residential areas.
By contrast, Stockholm, the other joint leader
in the buildings category, has been at the forefront
of energy-efficient building standards for
some time. The city benefits from its extensive
use of heat pumps, which make more efficient
use of electricity for heating. Insulation standards
are also high. All this pays off: Sweden has
years of experience building homes with a total
annual energy consumption of well below
2,000 kwh, despite its cold climate. By contrast,
new houses built in the UK that comply with the
country’s latest energy-related building standards
will consume an average of about 3,600
kwh.
Ideas from
other cities
From April 2010, London will start a trial
scheme for retrofitting homes to save energy,
providing some energy-efficiency equipment
for free, such as low-energy light bulbs and
standby switches, while charging for more
advanced measures.
Residents of Prague can benefit from a national
Czech programme for retrofitting
buildings with a €1 billion budget, which is financed
from a sale of CO2 emission permits
to Japan.
In 2001, Vienna began permitting the construction
of multi-storey buildings made primarily
of timber. This has helped to bring
about the development of a new kind of environmentally
friendly passive housing.
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