It is the first time hydrogen cell fuel has been used to deliver both electrical power and hot water for all domestic appliances in a house.

The last time the technology was used for power and heat in this way was on the Apollo space programme in 1969.

The trial is the product of a two year research project undertaken by social landlord, the Black Country Housing and Community Services Group, to lessen the dependency on fossil fuels.

The fuel cell system, supplied by Alternative Fuel Systems and with a maximum output of 4.4 kW for electricity and 3kW for heat, has been switched on at one of BCH's new homes in Sandwell.

In trial conditions it is producing 1.5kW of electrical power - enough to do household laundry and to heat water for other washing needs to a temperature of 60C (142F). This is comparable to the typical thermal output of a solar water heating panel on a summer's day.

Richard Baines, Black Country Housing project leader, said: 'Fuel cells are part of our energy future.

'They burn hydrogen to make electricity without any pollution.

'And when hydrogen is eventually produced from water and not, as now, from fossil fuels, we can begin to help stop global warming and reduce our reliance on scarce and dirty carbon-based fuels like gas and oil.'

It is hoped the new energy process will be used in a live setting in BCH homes within two years.

The research work and trial has been part funded by The Department of Trade and Industry, with sponsorship from gas supplier BOC, which has provided the hydrogen fuel for the project.

Fuel cells generate electricity by combining hydrogen gas and oxygen from the atmosphere in the presence of a metal catalyst - in this case an alkaline electrolyte.

As a result, the two gases react to form water, producing electricity and heat in the exothermic process.

'Laboratory experiments and computer predictions suggest that, of all the alternatives for combined heat and power systems, fuel cell output could well be the 'best fit',' added Mr Baines.