How are we supposed to make buildings more environmental? During the visit from Hamburg we have been working together to answer this question. We have been visiting schools, recycling centres, student apartments and environmental shops. In this report we will compare certain aspects of environmental buildings in Hamburg and Bergen, as well as explaining different energy-saving systems in Bergen.
During our stay we went to the Student Apartments in Grønneviksøren. These apartments may room as much as 727 people, and have parking slots for 360 bikes, and no parking slots for cars, which means that the students living here will have to use their bike or public transportation. These apartments are very energy efficient. In addition to the very efficient isolation, these apartments are also connected to the water heating network and a garbage tunnel network. The only problem with these apartments is that they are quite expensive due to several delays and stability problems during the construction.
In the past the student apartments in Hamburg were rentable for everybody and located in all parts of the city. Today, finding a rentable apartment is hard for students in Hamburg, and most of the apartments are located close to the university. Present, the student apartments are only located in special parts of city eg. Like Rotherbaum and Grindel. The student apartments are not as environmental as in Bergen because the buildings have to be cheap, to keep them rentable.
We have also visited the recycling centre in Rådalen. The waste to energy – plant there is owned by BIR (Bergen Intekommunale Renovasjonsselskap). BIR is responsible for collecting garbage in 9 municipalities in Hordaland, including Bergen. The plant produces energy by using the heat created when burning garbage to vaporize water. When vaporized, the water expands and the resulting pressure is used to create motion in a turbine, which generates electricity. After moving through the turbine, the still hot steam is used to heat water, which is then sent through isolated tubes to buildings in Bergen. Examples of buildings connected to this water heating network, are Haukeland Hospital, BHG and the student apartments in Grønneviksøren.
A large amount of ashes are produced when burning garbage. These ashes contain large amounts of metal and melted glass. These materials are separated from the ashes and recycled. Several poisonous and polluting gasses and large amounts of hazardous particles are released into the air when burning the garbage. The waste to energy plant has one of the most effective air cleaning systems in the world. The first step of the cleaning process is adding ammonia to the smoke. The dangerous NOx gasses in the smoke will then react with the ammonia, leaving water and nitrogen gas. After this lime (note: note citrus fruit) and active carbon is added to the smoke. Heavy metals in the smoke are “captured” by the large surface of the active carbon, and different types of acid react with the limestone. The remaining dust is the filtered. In the end the air is showered with water. Simple but effectively, the last remaining pollution is captured by the water, which is easier to clean. The filtered limestone and active carbon as well as the ashes not recycled is sent to an island outside Oslo and stored beneath the surface.
The energy consumption of Amalie Skram is reduced due to modern heating and energy saving systems, such as water heating and modern isolation techniques. The advantage using water heating is that heat can be transferred to buildings from local industry. The surplus heat from industrial processes is used to heat water which then is sent through tubes to buildings. These tubes need an effective isolation so that the water keeps warm. Smaller tubes are linking buildings to the main tube. Upon reaching a building, the water is sent through non-isolated tube in walls, floors etc. The heat will then escape from the water into the rooms of the building. In Bergen, heat from the recycling centre BIR is transferred in this way.
At Heinrich-Hertz Schule, solar panels have been placed on the roof to help supply the School with electricity. They are not effective enough to cover the energy consumption of the entire school, but it certainly does its part in lowering the costs and environmental impact. The teachers, as well as the students, are themselves inclined to take measures to save energy when they are at the school.
After working together with the students from Heinrich Hertz Schule, we have learned a lot about projects and political measurers concerning eco-buildings in Bergen. After several excursions and a lot of hard work, we are now able to answer our question. By improving the isolation of new buildings, the energy consumption may be halved. Examples of this are the student apartments in Grønneviksøren. These apartments have an improved isolation reducing the amount of energy used for heating. These apartments are also connected to a garbage tunnel system and are heated through the water heating system, using heat from the waste to energy plant which is sent to the city through isolated tubes. This system is providing heat to many important buildings in Bergen, including BHG. The electricity that would otherwise be used for heating may now be used for other purposes. The local government are making these eco-building projects possible by supporting environment-friendly projects.