But if the Ilisu dam is not built, Turkey should still eventually find environmentally friendly energy sources.

It can improve the efficiency with which it uses energy, and it can turn to renewables. Solutions like these would cost Turkey far less in many ways.

A year ago the World Commission on Dams published its final report. It was chaired by the South African Education Minister, Professor Kader Asmal.

He said: "It means nothing to build billion-dollar dams if your monuments alienate the weak. It means nothing to stop all dams if your protests only entrench poverty."

The commission said dams worldwide had provided many benefits, but often at too high a price.

Wind potential

It said rotting vegetation trapped under water released carbon dioxide and methane, both potent greenhouse gases, and this could cause more pollution than production of electricity from fossil fuels.

The commission concluded that there was far greater scope for using alternative ways of meeting people's needs, including renewable energy, recycling, better irrigation, and reducing water losses.

Aegean Tech is a Turkish technology and renewable energy group. It says: "It is estimated that in 2023 Turkey will need 600 billion kWh a year.

"If we pursue an intelligent policy, then in 2023 about one-third of the energy need of the country could theoretically be harvested from the wind."

Dr Smail Khennas is senior energy specialist at the Intermediate Technology Development Group (ITDG).

He told BBC News Online: "In Turkey's case, renewables would not be able to fill the gap in the short term, over the next five years or so.

Twice the average

"Ilisu would produce so much energy it will be quite a lot longer than that before renewables can provide the answer. But in the meantime, Turkey could work on improving its energy efficiency."

Greenpeace says: "The potential for Turkey to reduce its energy usage is massive. It uses twice as much energy per unit of gross national product (GNP) as the European average.

"In the last three decades European countries have increased their energy efficiency. However International Energy Agency figures show that Turkey's energy efficiency actually decreased during this period.

"In 1996 the cost of wasted energy was $4.5bn, roughly equivalent to the amount that Turkey spent the previous year on imported energy.

"The Turkish Chamber of Electrical Engineers estimates that up to 30% of the electricity generated in Turkey is lost during transmission and distribution from power stations to end users. The international standard is 6-6.5%."

Thinking small

Hannah Griffiths of Friends of the Earth (FoE) told BBC News Online: "Turkey is ideally placed to exploit its solar energy potential.

"It doesn't need centralised generators, but mini-power stations on the roofs of homes and other buildings.

"They could feed current into the grid by day, and the users could take electricity from it when the sunlight wasn't enough to meet their needs."