In 2000, ICLEI member city Barcelona (Spain) became the first European city to develop and implement a Solar Thermal Ordinance (STO). The STO made it compulsory to use solar energy to supply 60 percent of running hot water in all new buildings, renovated buildings, or buildings changing their use. The ordinance has been integrated into the overarching political and planning framework for climate change mitigation in the city.

Within this framework, Barcelona aims to achieve energy self-sufficiency in the long term through the use of renewable energy resources and the promotion of energy efficiency. The local government is leading by example, having installed renewable energy systems in its own buildings and facilities, including the use of solar thermal energy for water heating.

The commitment by Barcelona to an energy efficient future is further explored in the ICLEI Case Study series, in which the role of ICLEI members and other local governments as key drivers and implementers of urban sustainable development across the globe are illustrated. Emphasis is given to successful approaches, innovative models and transferable best practices in the field of sustainable urban development.

For more information, read the full Barcelona Case Study.