Sunday 26 June 2011

Your definitive guide to turning your home into a power station

Solar power stations have, so far at least, proved expensive follies singularly incapable of producing anything like the energy we so hungrily need. But for ordinary home owners, matters are rather different, as the multitude of solar-panel firms proves.
Indeed, small solar panels on our roofs can actually be a solid earner. It's not that they are any better than their industrial cousins - indeed, the amount of energy they produce would ordinarily be too small to justify their existence. At best, you'll usually only produce half the energy your home requires.

But then the very generous 25-year government Feed-in Tariffs (FIT), or subsidies, come in. This means solar panel owners get paid to have them, to encourage 'green' power.

The government has been heavily criticised for its benevolence: taxpayer groups complain non-solar users - ie, the vast majority of us - are being made to subsidise solar users. Indeed, the first tariff system worked out as the equivalent to a savings account offering more than 11 per cent per year - far more than any bank.

'Had we not acted urgently to reduce tariffs, the whole Feed-In-Tariff scheme would have been entirely swamped,' Climate Change Minister Greg Barker admitted.

The cuts targeted businesses, but for homeowners, solar can still make sense, although set-up costs are high - an installed solar electricity system costs £4,500 to £8,000 per kilowatt of output (we'll come to what that means in terms of power later); which means a standard 2.2kW system is around £12,000 (including VAT).

You'll need to be confident that you're staying put, in other words - the systems only start to pay for themselves after a decade or so. You'll also need to be in the right place - a home in Plymouth produces up to 50 per cent more solar energy than less sun-drenched locations such as Lerwick.
WHAT YOU CAN EARN

Under the FIT scheme, when you install a solar system, you get paid for the amount of electricity it generates, regardless of whether you use that energy (thus reducing your bills), or you sell it back to the National Grid (making money in the process) - so the bigger the system you install, the more money you'll make.

The average home uses roughly 3,400kWh per year: the maths used to calculate output is rather complicated, but roughly a 2.5kWp (kilowatt peak) system will provide just over half your power needs. Average tax-free profits hover around £1,000 per year.

The FIT is fixed for 25 years at the rate they are offering at the time of installation. The price of electricity you 'sell' back to the grid goes up with along with the general price for units of electricity.

'Previously, solar panels did nothing to improve the appeal of a property, but if you can prove your solar panels make a tax-free profit each year, I can see them attracting more than just the sandals brigade,' says Trevor Kent, former president of the National Association of Estate Agents.

Indeed they have piqued people's interest, and companies looking to cash in on the FIT scheme are offering free solar installation to your home. They receive the profit from the FIT while you get a healthy reduction in energy costs. But buying your own panels - even with a loan - makes better financial sense.
THE TWO TYPES OF SOLAR

There are two types of domestic solar technology:
Solar PV (Photovoltaic)

This type generates electricity.
Solar Thermal

This only heats water.

At present, the solar tariffs only apply to solar PV systems, but there are plans to extend these to the simpler and cheaper solar thermal systems, which cost just £3,000-£5,000 each.
SOLAR AND YOUR HOME

So is your home suitable? South-facing is ideal - you'll lose 15 per cent for east or west - as is a 25-45 degree pitched roof and around 30 sq m of roof space (all the energy figures quoted for systems here refer to 'ideal' homes). Shade from trees or buildings will reduce performance.

Planning permission is not generally required as long as it doesn't protrude more than 200mm above the roof line. Restrictions may apply for listed buildings or conservation areas - visit planningportal.gov.uk for details.
HOW ELECTRIC SYSTEMS WORK

With solar PV systems, each panel houses a cell made from layers of semi-conducting material, usually silicon. When light shines on the cell it creates an electric field. Choose between standard roof-mounted panels (the cheapest), built-in panels which sit flush within the roof, or solar tiles, which completely replace traditional tiling. Tiles are more expensive, but costs can be offset if your roof already needs replacing. Prices range from £4,500 to £8,000 per kWp installed.

With either system, a wire leads to a 'solar meter' in your loft which shows you how much money you've earned, then the electricity travels to your home electrical system, or back to the National Grid, where you can profit.

Energy isn't usually stored or saved up for use later. If you don't use it, the energy is sold back to the National Grid. The money you get for this is - slightly - less than what you'll pay per unit on your bills, so if you've got solar, it pays to run high-drain appliances such as washing machines during the day, when your panels will be generating electricity.
HOW THERMAL SYSTEMS WORK

Solar thermal systems employ a series of tubes filled with anti-freeze that are mounted behind glass on the roof. The sun heats the liquid, which is pumped through a coil inside your hot water tank generating temperatures up to 60ÂșC - perfect for showering. A two-panel system (4 sq m) should provide around 50-60 per cent of your hot water needs.

Although final details are still shaky and subject to change, the Department of Energy and Climate Change (DECC) has indicated that payments of £300 per system, and 8.5p per kWh of heat produced, could be o ffered to people installing solar thermal heating at home.

You'll have to choose between 'flat plate' and 'evacuated-tube' systems. Evacuated tubes are more expensive but o er greater e fficiency. Don't forget, you will still need a regular boiler to top up the hot water at night or on cloudy days.

Budget £3,000 to £5,000 for an installed system - kits start from £1,000, but you will need DIY experience and sca ffolding to install.


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Sunday 19 June 2011

The giant 'anaerobic digesters' that will convert our slop buckets to electricity


They are set to divide our communities as efficiently as they break down our waste.

Huge ‘anaerobic digester’ plants the size of two football pitches will be built across Britain as a multi-million-pound industry develops to convert waste food scraps into usable electricity.

Fuelled by the Government’s drive to introduce kitchen slop buckets in every home, the units can transform 120,000 tons of scraps into six megawatts of power, enough to power 6,000 homes 24 hours a day.
Critics call them unsightly and smelly, but those in favour regard them as the ‘future of waste’.

Last week, rubbish disposal giant Biffa opened the country’s first ‘super’ £24 million plant in Cannock, Staffordshire, and the £800 million company is planning more.

Biffa chief executive Ian Wakelin said: ‘I am a man in a hurry. Over the next few years I would like to see these really large plants around London, the North-East, the South-West and the West. This is the future of waste. It is taking food that could once only be sent to landfill and turning it into something of value on a truly industrial scale.’

The Cannock plant, whose 60ft containers tower over the landscape, is based on an existing landfill site.

Spread over several acres, it includes a vast storage shed in which lorries can unload the waste, pipes to carry the methane gas it produces, and a balloon to store gas.

Cannock gets much of its waste from local restaurants, nightclubs and pubs, but increasingly such plants will use leftover food scraped by householders into ‘kitchen caddies’ for separate roadside collection.
The Government is pushing the fledgling industry because it is required by European legislation to reduce its use of landfill sites.

The Environment Department predicts the industry could produce enough energy for nearly a million homes within a decade.

Liberal Democrat peer Lord Redesdale, chairman of the Anaerobic Digestion and Biogas Association, said the industry would bring down gas prices by making Britain less reliant on imported gas.

He said: ‘It’s a big ask but the Germans managed to build 1,000 new plants in ten years. This is not new technology. We are building on what is already out there.’

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Friday 17 June 2011

Eco charity boss travels length of Britain in electric car - for just £20


An eco-friendly charity boss has completed a gruelling end-to-end journey across Britain by driving 894 miles in an electric car using public charging points.

Kevin Sharpe, 51, stopped six times to charge his Tesla Roadster along the route, at a cost of just £20.

The electricity used by the car was a fraction of the £138 it would have cost in fuel in a typical family vehicle.
Each charge of his car cost Mr Sharpe £3 or £4 and allowed him 200 miles of travel at 70mph before he had to power his vehicle again.
The charity has created the network of nine public charge points in hotel car parks across the country.

They cost £250 to install and users are charged for the electricity they use.

Drivers can opt for a quick three-hour charge or an eight-hour overnight top-up using a 70 amp plug.

Mr Sharpe, of Bath, Somerset, and David Peilow, 34, a satellite systems engineer of Winchester, Hants, set off from John O'Groats in the £86,000 Tesla on May 21.

Mr Sharpe said: 'This is another landmark because these are production cars, not prototypes.

'Nissan has already produced the leaf which costs around £25,000 and Mitsubishi, BMW, Audi and VW are all set to go to market with affordable electric cars in the next two years.

'Tesla are planning a family saloon too with a 300 mile range and 45 minute charge time. 'You could coincide a trip with a meal at a service station say and make a long distance journey in the same time you would now.'

The Tesla Roadster, produced by Tesla Motors in California, is based on a Lotus Elise and is the first production automobile to use lithium-ion battery cells.
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Thursday 16 June 2011

Geo-Engineering Elimate Solutions


Lighter-coloured crops, aerosols in the stratosphere and iron filings in the ocean are among the measures being considered by leading scientists for "geo-engineering" the Earth's climate, leaked documents from the UN climate science body show.

In a move that suggests the UN and rich countries are despairing of reaching agreement by consensus at global climate talks, the US, British and other western scientists will outline a series of ideas to manipulate the world's climate to reduce carbon emissions. But they accept that even though the ideas could theoretically work, they might equally have unintended and even irreversible consequences.

The papers, leaked from inside the Intergovernmental Panel on Climate Change (IPCC), ahead of a geo-engineering expert group meeting in Lima in Peru next week, show that around 60 scientists will propose or try to assess a range of radical measures, including:

• blasting sulphate aerosols into the stratosphere to reflect sunlight into space;

• depositing massive quantities of iron filings into the oceans;

• bio-engineering crops to be a lighter colour to reflect sunlight; and

• suppressing cirrus clouds.

Other proposals likely to be suggested include spraying sea water into clouds to reflect sunlight away from the Earth, burying charcoal, painting streets and roofs white on a vast scale, adding lime to oceans and finding different ways to suck greenhouse gases out of the air and deposit heat deep into oceans.

The meeting is expected to provide governments with a scientific assessment of geo-engineering technologies, but is widely expected to be in favour of more research and possibly large-scale experimentation despite an international moratorium adopted by the UN last year in Japan.