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Home!! Next Energy Group meeting Tue 4th May 7.30pm!! Energy savingby Kevin Byrne - Transition Town Shaftesbury Energy Group Why save energy? Almost daily we are being urged by both the government and environmentalists to save energy in order to minimise climate change. Here in Shaftesbury we are very fortunate that one of the most obvious impacts, the rise in sea level, is not a real threat to us. There are other factors however that we will not be able to avoid. As our climate changes, extreme weather events will becoming more frequent, we have seen a number of times in recent years how flooding, drought or high winds have wreaked havoc on different parts of the country. Another factor that will impact on us in the coming years is the rise in energy costs. The worlds increasing demand for oil means we have been using far more than we have discovered for quite a long while, in fact, the last time more oil was discovered than consumed was in 1980. Oil companies naturally exploit the easiest oil fields first, leaving the more difficult and expensive until last. Experts predict that there will be a point therefore when we are unable to extract as much oil as we did the previous year and we will have passed the peak of maximum production, this phenomena is known as Peak Oil. Many analyst believe this peak was reached last year and in each future year we will see a progressive reduction in the amount produced. A similar effect is on the cards for natural gas. When demand outstrips supply prices will rise as we have seen over the last couple of years. This will be made worse as the world recovers from the present recession, demand for energy will again increase and so will its cost. As fuel resources become more scarce, energy security will become an increasing issue, both in our homes and as a nation. The UK is already a net importer of energy by quite a large margin and as the oil and gas reserves of the North Sea decline, the situation will get steadily worse. Over the last few decades, we have become increasingly dependent on reliable supplies of gas, oil and electricity and our homes have become increasingly vulnerable as a result. Clearly, anything we can do to minimise our use of fossil fuels will reduce the harmful effect on our climate, make us more resilient to disruptions in energy supply and save us money. What can we do? There are a large number of possible ways of saving energy and a few of producing your own, some measures will be more suitable than others depending on your home and your lifestyle. As fuel prices increase, more expensive energy saving measures and renewable energy technologies become more cost effective. There are some free measures that normally apply to us all, these mainly revolve around changes in habit and behaviour, many will be fairly obvious. For instance:
Many of the energy saving measures that cost money can still be self financing. Some medium cost measures that come into this category include:
There are other, more expensive energy saving measures such as multiple glazing, a wood burning stove/cooker or heat recovery ventilation that are often difficult to justify purely on a financial basis but there are often very valuable spin-off's such as improved comfort, energy security, health benefits and an increase in the value of your home. Again, expert help should be sought to make the best value from your investment. It is invariably more cost effective to save energy rather than to generate it ,so all the necessary steps to saving energy should be taken before considering installing a renewable energy system. If however you do get to that stage, a solar thermal system to produce your hot water will often be the first step in terms of best value for money. A typical installation cost would be £3000 to £5000 and your home will need to have a suitable roof or wall for the panels that faces near to South. Flat panels are the least costly however the more modern vacuum tube arrays are more efficient, particularly during the winter. There are two common ways of generating electricity, by using solar photo voltaic panels or a small wind turbine. These have both become more cost effective recently due to the new feed in tariffs recently announced by the government. The power from these that you do not use yourself is fed from your home into the national grid and you are paid for each unit of electricity at an enhanced rate. Both systems have their own requirements for installation but the effectiveness of a wind turbine is particularly dependent on its location. Lastly, though not technically a renewable technology, heat pumps deserve a mention as they are often viewed as a magic solution. While claiming efficiencies of perhaps 400%, i.e. for each kilowatt of electricity supplied they can produce 4 kilowatts of heat energy, these headline figures often do not give the true picture. These efficiencies are only normally produced under near ideal conditions of internal and external temperatures and when used in conjunction with an underfloor heating system. The driving energy will usually be grid supplied electricity, this is in itself expensive and very inefficient in terms of its environmental impact which brings the running costs back to that of a conventional gas or oil based heating system. Where a heat pump will score however is in a situation where electricity is the only available energy source for heating or where the electricity is locally generated from a renewable source such as a water turbine, these situations are unfortunately few and far between. Here's an interesting article from the Observer 21 September 2008. Food for thought! http://www.guardian.co.uk/environment/2008/sep/21/renewableenergy.alternativeenergy After the film 'End of Suburbia' we had a discussion about local energy generation and the way communities in Scandinavia had bought wind turbines for themselves. The people of Swaffham also requested Ecotricity to build windmills for their town. I'm not an expert on the effectiveness of onshore windpower and I've read contradictory things about it - but it seems to me that if you just think about climate change, then we can easily argue against windmills - as is the case in Silton - but as soon as you think about peak oil and local energy security then the pros and cons of a local windmill seem very different. Would it be a good idea for us as a town to welcome a windmill on the top of the hill? Amanda Agreed if there's no room at the top you can build one in my garden at the bottom of Gold Hill! rob |