Sunday, September 02, 2007

Architecture and sustainability

This review will address the issues of sustainability and discuss the way in which the impact of current building patterns on climate change have influenced design of the architect Bill Dunster when he created the Beddington Zero Energy Development or BedZed.

Climate, ecosystems, and human society interact in complex ways. In the past the environmental stress caused by man activities was responsible for the extinction of populations. The inhabitants of the Easter Island became extinct because of the destruction of the forest that sustained them. The Mayas over-farming provoked the erosion of the soil. Subsequently, the Mayan civilisation began to disintegrate as people left. By creating a system of irrigation which left only mineral salts behind, the Mesopotamians poisoned their fields These examples are the historical proofs that our entire society is linked with the natural resources and caring for the environment is safeguarding our society.
Sadly, today we know that our entire planet suffers. Some believe that it is because of man activities but others do not share this belief, but what do the facts tell us? We know that the CO2 is about 30% higher than at any time, and the methane is 130% higher than at any time; and the rates of increase are absolutely exceptional: for CO2, 200 times faster than at any time in the last 650,000 years. “The fact that the relationship holds across the transition between climatic regimes is a very strong indication of the important role of CO2 in climate regulation” said Professor Stocker. How to inverse the problem ?

People must adopt a responsible and ecologically ethical way of living and sustainability cannot be achieved through building alone. Figures show that UK families spend one third of their annual carbon emissions on transport; one third on heating and power; and the rest on consumption of imported groceries. Therefore, a development cannot be truly sustainable unless these 3 issues are also addressed. This is why building can’t be considered in isolation from their surroundings when we think of sustainability. We must understand buildings in the wider context of geography and society. The Architect Bill Dunster worked on these issues and produced The Beddington Zero (fossil) Energy Development (BedZED), 39 in Sutton, which is Britain’s first urban carbonneutral development. It is a "carbon-neutral complex," an urban infrastructure that generates enough heat and power from renewable sources within its borders to offset consumption of imported fossil fuel.
The 82 conventional maisonettes and 18 live-work units are not only low-energy, they include an all idea of green living. "There is no point in designing low-energy offices if you have to drive 25 miles in your car to get there," said Bill Dunster. Following the same principle all the materials specified for the BedZED development were sourced within 35 miles of the site. For the exterior carpentry and bridges, and half of all site materials they were recycled or reclaimed, including paving, structural steel, and most of the interior carpentry. In the same vein, the site includes important facilities to avoid carbon emissions resulted from transportation. The idea was to do as much as possible on site. The team included live/work unit, office workspace, day-care centre, cafe and sport facilities. Moreover, in order to travel when needed, the architect encouraged eco-friendly transport such as electric and LPG, the electricity being provided at the parking spaces to charge electricity to up to 40 electric cars.

The second issue is about the heating and power. Bill Dunster gives a description of the BedZED design as “A sunny, super-insulated, carefully ventilated cave". Basically, the concept was to have a big thermal mass in order to have a weekly level of heat storage. In order to do so the buildings have sedum roof and a grass-covered patios which provide a passive cooling system. The buildings have windows as much as possible on the south-facing side with the sunroom and Triple-glazed windows dressing the east, west, and north facades. This passive solar strategy covers between 20 and 30 percent of winter heating needs. Moreover, compared to a similar home built ‘traditionally’, the carbon emissions were reduced by 56% through insulation, double and triple glazing and energy efficient appliances and light bulbs. The site produces its energy by continuous strips of photo-voltaic cells placed on the roof, integrated into the double-glazed sealed window which supplies 11% of the site’s electricity. To complement the need of energy, one co-generation central, running on wood recovered in the surroundings , reduces the need of heating by 90% and the consumption of electricity drawn from the city electricity network by 60%. (“BedZED”, 2005). In order to tackle CO2 from food miles, every day, fresh seasonal products come directly from the UK farming industry which are located in a close area. It has the advantage of providing organic fruit and vegetable as well as wine and beer and also it allows to reduce the packaging and chemical usage. Residents can also grow their own food in their gardens and on the on-site mini-allotments. Bill Dunster added "We're also making it so easy and convenient to lead a green lifestyle that you don't have to think about it; you just default to it.". But is it a realistic view?

Porteous Colin comments that the participatory role of the user/client gains further emphasis and what needs to be recognised at the outset is that expectations of performance are rarely met, and the main reason for this is that designers are not realistically predicting or addressing the actions of lay users. An example comes to support this comment. One occupant of a two-apartment flat had a bill from July to September 2004 that averaged £27 per month. In a period when there should have been no space heating and a reasonable amount of electricity generated by the PV arrays it seems abnormal to have this sort of bill mainly due because of water heating and the use of electrical appliances. Giving an opportunity to have a very efficient house with adjustable controls and low energy systems that are in place still requires the participation of the occupant and a logical use of these features, and we do not know what to put first, the energy efficient performance is extremely important but so is the well being and thermal comfort.
This is why the comparison of the BedZED projects with another project, the co-housing project in the Vauban district of Freiburg Germany is of interest. One of the main aim of this project was to promote the participation of the residents who were actively involved in the project and understood the responsibilities linked to it. The hot water was metered and billed and the small amount of energy supplied to radiators was included with the rent. It can be noticed that the environmental awareness in Germany is high even in the political and social systems. This example shows that a project like BedZED needs the full support and awareness of the users and some knowledge of the aspects of environmental development.

BedZED presents more than an extraordinary example of sustainable design: It is also a "serious study in high-density, contemporary urban living," says Bill Dunster. The development's real success, however, is its appeal to the homebuyer with an environmental agenda. We could say that for all these reasons buildings will be ‘zero energy’ only in theory unless the occupant make changes in his lifestyle in order to think ‘ zero energy’.

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