Heat Island Effect
All urban areas experience an Urban Heat Island Effect (UHIE): this is the increased temperature of a built-up area compared to its rural surroundings.
A modeling scenario undertaken in New York by the New York Heat Island Initiative determined that providing 50 per cent green roof cover within the metropolitan area would lead to an average 0.1-0.8°C reduction in surface temperatures.
It noted that for every degree reduction in the UHIE roughly 495 million KWh of energy would be saved. There is no reason to doubt that comparable reductions could be achieved in the UK.
