Useful energy, environment and sustainability web links evaluated and selected by a network of subject specialists are listed below: 

Business Council for Sustainable Energy UK
Forum for UK energy industry, government and other stakeholders on sustainable energy

Centre for Alternative Technology
Provides practical solutions to environmental problems

Centre for Sustainable Engineering
A national clearing house for information, expert analysis, practical application, knowledge transfer and commercial benefit in relation to sustainable technologies

Energy Institute
International (UK based) professional body for energy industries

Envirotech.org.uk
Website concerned with embedding sustainability principles into engineering and construction

IMechE Energy, Environment and Sustainability Group
News, events and committee information

International Energy Agency
Acts as energy policy advisor to 26 Member countries

World Energy Efficiency Association 
A clearinghouse for information on energy efficiency programs, technologies and measures which publicises international cooperation efforts.