Winners of the 2006 Ashden Awards for Sustainable Energy were announced in Britain with an International 2nd Prize Award going to Shaanxi Mothers Environmental Protection Volunteers.

Shaanxi Mothers Environmental Protection Volunteers (£10,000) took second prize in the Health and Welfare Award for, in the words of the judging panel, "their determined efforts to bring all the health, economic and environmental benefits of biogas technology to farming families in rural China".

Led by their founder, Wang Mingying, the Shaanxi Mothers have overseen the installation of almost 1,300 biogas systems in farming households across the province. The main source of the gas is waste from humans and household pigs. By replacing wood as a cooking fuel, it is saving families time and money, as well as contributing to China's reforestation efforts.

The project is a triumph for the Shaanxi Mothers – a largely voluntary group of women whose commitment and persistence have overcome huge obstacles to create a thriving environmental success story.

Finding alternatives to wood and coal for cooking fuel is becoming an increasingly urgent task in China's central Shaanxi Province. Like many parts of China, it has suffered from decades of deforestation and soil erosion.

The government is now addressing this by placing severe restrictions on tree felling and wood cutting, and undertaking a reforestation programme which is changing the face of the landscape. The terraced hillsides are now out of bounds to crops, except a limited ratio of fruit trees. Instead, farmers are paid to plant (and tend) trees; everywhere you look, there are saplings and small trees coming up.