The 'Merton Rule' is the groundbreaking planning policy, developed by Merton Council, which requires the use of renewable energy onsite to reduce annual carbon dioxide (CO2) emissions in the built environment.
Merton developed the rule and adopted it in 2003, its impact was so great that the Mayor of London and many councils have also implemented it; it has also become part of national planning guidance.
Over the past few years, Merton has been working closely with other authorities, professions and industry to embed the Merton Rule. This work is not only leading to big CO2 reductions, but it is helping to create an industry that can respond to the needs for affordable renewable energy
The definition of what is referred to, as the 'Merton Rule' is a prescriptive planning policy that requires new developments to generate at least 10% of their energy needs from on-site renewable energy equipment.
The most commonly accepted threshold is 10 homes or 1,000m2 of non-residential development - though this is sometimes lower. This is the accepted definition by local (and regional) planning authorities, academic institutions, trade and professional bodies, and the development, construction and engineering industries.
Around half of UK’s local authorities introduced the Merton rule, however, each one applies it to a different degree – for example, some might “expect” a developer to enforce a 10% rule, some will “require” 20% or more.
However, much of the value of the Merton Rule has been superseded and eclipsed by the Code For Sustainable Homes and now the Feed-in Tariff or 'Clean Energy Cashback' scheme which provide a far greater incentive for developers and home owners to install on-site renewable energy systems.