MANILA, March 22 (Xinhua) -- The Asian Development Bank (ADB) said on Thursday that it signed loans to an Icelandic and a Chinese geothermal energy company to expand environmentally sustainable district heating services in China.

The Manila-based bank said the loans, with a total of 250 million U.S. dollars, will be obtained by Arctic Green Energy Corporation (AGE) from Iceland and Sinopec Green Energy Geothermal Company Limited (SGE) from China.

ADB said in a statement that both companies are world's leading service providers on geothermal technology and energy.

"This is a landmark project for Asia. Geothermal district heating can provide millions of citizens with safe and stable heat access while dramatically reducing air pollution and greenhouse gas emissions and the reliance on fossil fuels," said ADB Vice-President Diwakar Gupta.

"How cities are heated or cooled in the 21st century will determine the outcome in the fight against air pollution and greenhouse emissions," said AGE Chairman and Founder Haukur Hardarson.

"Joining hands with ADB will help strengthen our long-term partnership on sustainable geothermal development to fight against air pollution and reduce greenhouse emissions. We aim to replicate our successful collaboration across Asia," said SGE Chairman and Sinopec Star Vice President Liu Shiliang.

ADB said geothermal district heating extracts thermal energy from beneath the earth's surface for delivery to households and business through dedicated pipelines. It offers an alternative which is sustainable, stable, and cost-competitive to coal and gas, has zero-emissions, and can be integrated into existing networks to replace heat sources.