Wind and solar energy could be used to set up mobile phone networks in rural areas of the world without power.
A pilot project was carried out in Swindon in the UK
The world's first mobile phone base station powered by wind and the sun's rays will soon open in Namibia.
The trial follows a pilot held in Swindon, UK, led by Motorola. Mobile firm MTC Namibia will run the cell.
"We firmly believe we need a solution to go into rural areas and the key is speed - we need a quick roll out," said MTC executive Joachen Traut.
"Namibia is a huge country with only two million people - to get power to rural areas is very expensive.
"You are paying US $8,000 per kilometre to get a grid power line. And to get on the grid you can wait a year or two to get a power line."
MTC has been using base stations powered with just solar energy but will turn to the wind for the first time for the trial in the village of Dordabis, 40 kilometres east of the capital city Windhoek.
Linda Brown, GSM solutions manager for Motorola in the UK, said: "We have to generate power significantly higher than what the cell needs for us to pass on power to the base station."
The base station needs between 1,200 and 1,500 watts and to meet that demand the site will have a six-kilowatt turbine and four solar panels.
"In Namibia the turbine and solar panels will also be running the base station with traffic on it, the peripheral communications, vsat (satellite transmitter/receiver) and even the protective fencing around the site," said Ms Brown.
She said: "Capital costs for wind and solar are in the same range as a grid connection. But the roll out time is an advantage; it's much faster.
"Operating costs are much better than a grid connection or using diesel.
"We realised there was a market for these alternative power supplies to cell sites to cover both the fact that often power cannot be got to the region or if a grid connection is very costly."
Mr Traut said the cell would serve about 1,500 people living in the village as well as farming communities about 30km away
The network will support GSM, GPRS and Edge connections.
"The network will mainly be used for voice," said Mr Traut. "The area is popular with tourism and some business people will use data."
Motorola is also looking to work with networks in other countries.
"This solution is perfect for areas only accessible by helicopter - that's where we would be looking to deploy this technology.
"We are also in discussions to deliver a service in Asia."
In India a separate trial from Ericsson is using biodiesel to power mobile base stations.
Biodiesel has a lower environmental impact than conventional fuels and crucially, can be grown and processed locally.
Although at pilot stage, the scheme hopes to have up to 10 base stations operating in Pune, in the Maharashtra region of west India, by mid-2007.