Households that have been paying over the odds for their electricity may be surprised to learn that some suppliers are actually prepared to pay them for the energy they use.

Good Energy pays households that generate their own electricity using wind turbines or solar power, even if it is then used for personal consumption.

Most power companies now pay households who sell surplus energy back to the supplier, but Good Energy will pay for anything you generate. The firm makes its money from charging its 21,000 standard customers.

The government is expected to announce tax breaks for households that generate their own power and sell any surplus back to the energy companies in the forthcoming budget — but experts warn that even with the sweeteners you are unlikely to make back the set-up costs.

All the main energy suppliers, apart from British Gas, have recently introduced special tariffs that offer between 4p and 11p for every kilowatt hour (kwh) of energy sent back to the supplier, but they rarely pay enough to make it profitable.

There are currently some 80,000 microgeneration units in British homes, including rooftop wind turbines and small solar-powered units, but that figure is set to grow now that DIY stores such as B&Q sell them.

The use of microgenerators is being encouraged by the government through a grants scheme that covers some of the cost of installation. And the chancellor, Gordon Brown, is expected to announce tax breaks on any money made selling energy back to suppliers. Microgeneration equipment already has a reduced Vat rate of 5%.

However, research by comparison firm Uswitch shows it could take up to 70 years to offset the cost of installation, and the tax breaks are unlikely to make a big dent in this.

Uswitch said: “Microgeneration remains cost-prohibitive for the majority of UK consumers and is really best for those who want to create a self-sufficient lifestyle and can afford to do so.”

Dave Sowden, chief executive of the Micropower council, also urges caution.

He said: “People should only consider microgneration after they have made every effort to ensure their homes are as energy efficient as possible.”

A typical one-kilowatt domestic wind turbine will cost upwards of £1,500. With installation, this could rise to £2,500 or £3,000. Larger systems in the region of 1.5kw to 6kw, which will cover personal consumption and leave enough to sell back to suppliers, come in at £4,000 to £18,000.

Another option is solar panels, which can cost about £9,000 for the average household, whereas hydro power can cost around £25,000 to install.

You will also need an export meter to record what energy is used and how much is being sent back to your supplier. They cost about £120 a year to rent.

Grants are available (0800 915 7722; lowcarbonbuildings.org) for those who can prove that their home is as energy-efficient as possible. The grants can cover up to 50 per cent of the cost of solar panels and up to 30 per cent of other equipment. There is £500,000 worth of grants available each month, and it is allocated on a first-come, first-served basis.

You might spend £13,000 after your grant on a wind turbine capable of generating enough to sell back to your supplier, but you are unlikely to make the costs back in your lifetime. You would make an average of only £14 a year by selling your surplus back, and you would also save £388 on your energy bills. But it would still take 32 years to recoup your set-up costs.

Npower and Powergen pay the most at around 10p per kilowatt hour (kwh), although prices vary depending on region. EDF pays 7.64p per kwh, while Scottish & Southern pay only 3.8p.

Even if you don’t make enough to sell back to the supplier, microgeneration can still reduce the cost of your energy bills. The average electricity consumption of a British household is 3,800kwh a year. Microgeneration can cover a big proportion of this. For example, a 1.4kw wind turbine with an annual output of 2000kwh could supply about 60 per cent of the power consumption for the average British home — a saving of £200 a year.

Tim Start, 48, and his wife Fiona, 47, installed 3kw solar panels at their home in Hereford-shire last May for £16,300. They received a grant of £7,500.

The panels produce about three-quarters of their electricity needs. The remainder is supplied by Good Energy.

The company, which has 250 customers who produce their own energy, pays 4.5p per kwh of electricity produced — and not just for the energy that is sent back. The Starts have so far received £103.

Good Energy encourages the generation of renewable obligation contracts (Roc) which were introduced by Ofgem in 2002 as part of its drive to encourage green energy. For every mega-watt hour of energy produced from a renewable source, the industry receives a Roc from Ofgem as an incentive.

Domestic producers of energy can also be awarded Rocs. Good Energy buys these from its customers and sells 90 per cent of them on at the current market rate of £40 each. It tears up the remaining 10 per cent to encourage the creation of more Rocs.

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