Solar construction and wastewater avoidance
(Hamburg)
Source: Hamburger Bildungsserver
In the north of Hamburg (pop. 1,7 million), at the fringe of the Bramfeld district, approximately 10 km from the city centre, the “Solar Project Karlshöhe” was created on the site of a former state farm. The joint pilot project of the Federal Research Ministry and the Hamburg department of works features 124 residential units in 86 terraced houses. Together, they possess a combined solar collector area of over 3000 m², and they are connected to a close-distance heating grid with a 4500 m³-capacity long-term geothermal heat accumulator via a heating switchboard. The result being that approximately 50% of the total heating required for warm water and room heating can be covered with solar energy on average per year.
Source: Silvia Schubert
The „Ecological Estate Braamwisch“ with 25 terraced houses and a sum total of 40 residential units is part of the “Solar Project Karlshöhe”. The estate also includes a common building as well as diverse community areas and parking spaces for car-sharing. In compliance with ecological and social demands, the association „Ecological Estate Braamwisch“ developed a group of serially produced wood frame-type buildings assembled from modular elements. Joint features of all the buildings are the compact outer shape with a steep lean-to roof and the low energy standard with very elaborate insulation, wind-proofing, regulated ventilation (partly with heat recovery) and heat protection glazing.
All residential units feature dry composting toilets and two separate water circuits. The estate’s own grey water reed bed purification plant and the clearing pond that goes with it purify the wastewater and carry it off to nearby waterways. This means that the estate does not produce any untreated sewage, hence dispensing with the need to be connected to public canalization. This not only helps to reduce the operating costs, but also the consumption of potable water, as some of the treated water is re-used and rain water is also being collected. The resulting savings are expected to amortize the increased construction costs (by approximately 25.000 DM / 12.780 euro) in seven years. The humus produced independently from kitchen waste and faeces (approximately 40 litres per household per year) is used in the house gardens. The organization of the client community in the form of an association has proven effective, most of all in the negotiations with the authorities.
| Year | Event |
|---|---|
| 1994 | Competition for the solar project Karlshöhe |
| 1996 | Completion of 1st construction stage |
| From 1996 | Construction of the “ecological estate” Braamwisch |
| 1997 | Commissioning of the short-distance district heating network |
| Dec. 2000 | Estate largely completed |
Source: Silvia Schubert
Source: Silvia Schubert
Source: Silvia Schubert
This estate shows that economizing on drinking water and managing wastewater can be done so thoroughly, even within an urban settlement context, that one can do away with the connection to the public canalization system altogether. The combination of composting toilets, separate water circuits and an own wastewater treatment plant provides the residents with noticeable cost savings and is entirely in keeping with a “recycling economy”.
The projekt site ist to be found at postal code: 22175 - town: Hamburg - street: Braamwisch.
Record inserted on 01.06.2003 by Lehrstuhl für Planungstheorie und Stadtplanung, RWTH Aachen and updated by theFederal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) within the Federal Office for Building and Regional Planning (BBR).
Last update: 20.08.2008
