ANNABERG MUNICIPALITY, GERMANY
District Annaberg is located in Germany in the south of Saxony at the border to the Czech Republic.
Some Key Figures
LOCAL GREEN CITY BUILDING STRATEGY:
Main focus for developing local strategies in Annaberg District is the investigation and planning of reasonably cheap energy supply from geothermal energy, solar and biomass. Furthermore focus is on energy renovation of historical buildings and the use of natural building materials.
Urban Case Study Area
The City Ehrenfriedersdorf is an old industrial city. It was founded in the middle age as a mining town, as there was found tin mink. Tin mink was extracted until 1989. In the 19th century but primarily in the 20th century other factories where built, so for example the shoe factory “Panther” as the biggest. During the economic heyday of Ehrenfriedersdorf there were more than 4000 employees in the city and more than 7000 inhabitants. The location of the city is placed directly at important traffic infrastructure like the Street B 95 from Leipzig via Chemnitz to Annaberg-Buchholz and Karlovy Vary in the Czech Republic and the Street S 222 from Aue, Zwönitz and Geyer in the west side of the Ore Mountains to the mining town Freiberg in the east side of the Ore Mountains up to Berlin, was advantageous for the urban development. These streets also are the connections to the highways of the region. Now there are three traffic areas. So other new enterprises and some of the buildings of the former mining company now use the area of the former shoe factory too. And directly at that main street B 95 a new trade area was created. Now there are more than 150 smaller and bigger enterprises and companies in services, trading, metal, paper and textile processing, transport and workshops. More information you can find under www.ehrenfriedersdorf.de
The centre of the City is the selected project area. There are located the market place, the town hall, the building complex with kindergarten “Sonnenhügel” , the primary school and the secondary school, shops, and restaurants. It is located at the main street B 95 from Annaberg-Buchholz to Chemnitz and there are historical buildings from the 18th, 19th but also some from the 20th century. It directly belongs to the redevelopment area of the town.
Sustainable development of this area belongs to the main objectives of the integrated urban development strategy of the town. Renovation of the historical houses, possibilities of a better lifestyle near the market, increasing attractiveness for citizen and also for guests, decreasing running costs of flats, good infrastructure will stop the migration of citizen during the next years.
The city part of Aigen goes from the Kapuzinerberg on the right side of the river Salzach till the south border of the city. Aigen had till the 19th century a small centre with a church and the castle of Aigen and a agricultural structure with some farmhouses and manors. Till today the historical buildings in the old centre do exist. After 1945 there were some bigger settlements built and since the 1970 especially on the attractive western hillside housing areas were built.
This part of the city is mainly used as living area (blue colour) especially the hillside is only used as living area. In these areas there are only a few buildings for shops, trade or service.
Energy and Environmental Screening
This map shows the areas of heat energy supply by the district heating system (pink) and demonstrates the very good pipeline net for natural gas (yellow). Only outside of the direct urban area fuel oil is used for heating (cyan). But the figure also demonstrates, that there is a start up in using other, namely renewable energy sources like wood (brown points) or geothermal energy (red). Because of old mines the geothermal energy supply could play a more important role in the future (blue surrounded areas).
Green City Building Project Results
By help of the project “Green City Building” Ehrenfriedersdorf wants to create good examples of using geothermal energy and of renovation of buildings like the kindergarten and the historical house of the secondary school as a basis of follow up measures in the future. These objects were selected very conscious, as they are located in the city centre – redevelopment area already fixed by a resolution of the town council. Together with the urban development concept INSEK the town council decided that a sustainable urban development is the main focus in the future of the city. Hindrances on the wanted way were actually open financial questions but also open technical questions for example in using water from mines in heat pumps or how to realize measures of energy saving of historical houses. Project Green City building helped to find answers for those questions.
The realization of the pilot project was used to prepare a strategy for increasing the use of geothermal energy in the area of the city centre. To realize the strategy it was necessary to work out recommendations about technical questions of the use of geothermal energy. This can help owner of houses, investors, planning engineers and so on to find their own solutions, to create plans, calculate costs, to find additional financial sources and to realize their projects.
An important result of first studies, made in Saxon and in other lands of Germany, is, that the natural potential to use geothermal energy is very high. It is much higher than the potentials of biomass, energy from water or wind or of solar energy. And this source is usable for example during wintertime too – that time, where you need the most energy! Therefore it is to assume, that experiences, won during the realization of the pilot project will be very interesting also in other regions of Saxon and outside of Saxon and also in Europe.
A special study was made in cooperation with Technical University Dresden for developing strategy for renovating historical protected buildings (“Monuments”).
Design Work and Testing
Design work and testing for the 2 selected pilot project buildings was carried out in close cooperation with experts from Technical University Dresden regarding the special developed strategy for renovating historic “protected” buildings.
The building of the kindergarten “Sonnenhügel” was built in the 1980th. It was a standard building for schools and kindergartens in the former GDR. The building material was concrete and, as to be seen, glass. During the last years only important repairs, so at the roof for example, were realized. But there were no measures of energy saving. So there were important warmth losses and therefore high heating costs.
About several years it has been planned to supply the building with heat energy of the geothermal plant, located in the secondary school. But this presupposes a renovation of the building. As it is used by children with an age of some months to seven and eight years a combined system of foot under floor and wall central heating was in discussion as well as the usage of natural building materials like loam for wall covering was in discussion, to have well microclimatic conditions in all rooms in the future. After design work the renovation work started in November 2007.
THE SECONDARY SCHOOL “SCHULE DES FRIEDENS – SCHOOL OF PEACE”
The first school already existed in 1556 in Ehrenfriedersdorf. But the House of the secondary school was built between 1894 and 1897. Brick, natural and sandstone, wood and slate on the roof were the building materials. This house is the place of one of the first geothermal heating plants of the region. This plant was reconstructed in 2005 and now it is able to supply the secondary school, the primary school and the kindergarten with heat energy. By the capacity of possible heat production it would be able to supply one or two other buildings with energy too. But the old windows and energy bridges caused by constructional details of the house were the reason of energy losses. Therefore it was necessary to renovate this building too, to ensure an efficient use of the geothermal energy in the future. After finished design work construction work comprising renovation of façade, inside walls and windows was done in 2007. Testing will partly be performed by the pupils monitoring energy consumption and looking for ways to decrease use of electricity.
Local Green City Action Plan has been worked out for a new house building area “Wiesenstrasse” where all experienced Green Build tools from Green City Building will be used to optimize into sustainable building quality. This will be an area with new buildings heated by geothermal energy and centrally supplied by mining water as the energy source.