Recently a group comprising councillors, officers and young people from Epping Forest visited the Beddington Zero Energy Development (BedZED) in the London Borough of Sutton. The purpose of the trip was to learn more about sustainable development in practice.
BedZED is a prime example of ‘brownfield’ land redevelopment. It was a works unit that is now a community of 82, 1-, 2-, 3- & 4-bedroom flats and houses both for sale and rent; community facilities including a shop, café, sports facility, healthy living centre and a childcare facility; and communal green space and private gardens.
‘Brownfield’ Land:
An objective of sustainable development is to make prudent use of resources. This includes the use of land. The Government agrees that it is nearly always better to use land that has been previously developed (‘brownfield’ land) rather than use new greenfield land.
The houses face south and have large tall conservatories. This allows maximum use to be made of the heating effect of the sun on glass. Optimum use is also made of natural light, cutting down on the amount of electricity needed. The windows are triple glazed, whilst their timber frames reduce heat loss.
Essex is already one of the driest counties in England and the effects of climate change and additional dwellings in the future could make water an even more scarce resource in the county. At BedZED, 18% of daily water consumption is met by rainwater and recycled water, stored in large tanks built into the foundations. It may look slightly ‘rusty’ but it still flushes the loo! Low growing ‘sedum’ plants on the roofs absorb water to reduce surface water runoff (a problem with developments that have large areas of roofs and hard ground surfaces). Insulation for the roof is provided by a waterproof membrane, then a layer of soil, and the sedum. It never has to be cut, provides a habitat for insects and birds, and looks rather nice too.
The wind driven ventilation system is perhaps one of the most striking features of BedZED and evokes many responses. The cowls on the roof allow air to circulate naturally around the homes and offices without the need for air conditioning or central heating. They use no electricity and recover 50 – 70% of heat from the out-going air. Heat loss from the buildings is drastically reduced by an ‘overcoat’ of super-insulation to the roofs, walls and floors, so that heat from sunshine, lights, appliances, hot water, and everyday activities such as cooking, keep the houses cosy and warm. The thick walls of the building prevent overheating in the summer and store warmth in the winter which is released slowly during cooler periods.
A combined heat and power unit on the site can supply all of BedZED’s heat and electricity. This is fuelled by waste timber from local tree pruning which results in no (net) carbon emissions. All the homes are fitted with photovoltaic solar panels which convert the sun’s energy into electricity. They received a European Union ‘Thermie’ grant. This electricity will be used to power electric vehicles (and has enough potential for 40 electric cars) thereby reducing the need for fossil-fuelled petrol and diesel powered transport.
For more information on BedZED and sustainable living, visit their website at www.bedzed.org.uk