Fighting climate change by architectural design
Declan Butler has a feature (subscription required) in this week's Nature on the potential of green architecture for mitigating climate change. On his blog, he writes:
It’s been one of the most challenging articles I’ve had to write, as I had to leave out so much, but at the same time one of the most satisfying. This is a hugely important topic. Buildings account for up to half of all energy consumption, and are the biggest single contributor to greenhouse gas emissions. Much attention is given to exotic future remedies, such as carbon sequestration and clean coal. But a way to slash emissions using existing technologies is sitting under our noses: simply rethinking how we design the buildings we live and work in, to use much less energy.The arguments for building with energy needs met largely by marrying with the local environment and passive strategies are so compelling that the research for this article is persuading me to switch my own plans to buy a place in French Touraine, where I live, to instead build a zero-energy home — no small challenge, though, given that French builders are far behind their German, Swiss, and Austrian neighbours here.
Image: Low-income “passive” terrace houses in Lindas, Sweden; M. Wall
Comments
As a german architect and energy consultant for the renovation of buildings, I built several new low-energy houses in southern Germany, as well as i supervised the modernisation and renovation of older houses in the past decade.
In my opinion the biggest pay-offs in CO2-reduction and energy-saving will not only come from new buildings. There are huge potentials in putting the existing building stock to a up-to-date-level in energy-efficiency and the use of renewable energy sources.
In Germany, for example, more than 75% of the residential houses were built before 1983. These houses are responsible for more than 90% of the total primary energy consumption of all residential houses. Typical primary energy needs for these homes range from 250 to 500 kWh/m² per year or even more.
A well planned renovation of a house built in the 1950s - 1970s can easily reduce its primary energy consumption below 100 kWh/m² per year by using standard thermal insulation, modern heating systems, solar power, etc., whereas new residential buildings must be built in low-energy-standard anyway, according to EU-wide laws. While the number of houses being renovated is increasing, the market for new homes currently is getting smaller year by year.
Therefore it will have a larger and faster effect, for us and for the climate, if we increase efforts in the renovation and modernisation of existing buildings, rather than to put all hopes on the construction of zero-energy or even plus-energy houses.
Posted by: Reinhard Maier-Trommeter | April 8, 2008 12:34 PM