Installing certain renewable energy technologies, such as solar panels and biomass boilers, has now been made simpler since Permitted Development Rights were introduced in April 2008. In England, requirements for planning permission for most domestic microgeneration technologies have now been lifted. There are, however, certain restrictions. For example, roof mounted solar PV and solar thermal panels are permitted unless they protrude more than a certain distance or are on the principal elevation facing onto or visible from the highway in buildings in Conservation Areas. Different restrictions apply to stand alone solar PV and solar thermal panels.
The UK Planning Portal: This is the government's online service for planning, and it includes an 'interactive house' which is a simple visual guide outlining common household projects. Links take you to further information including a section on greener homes.