The balance of the annual heating and cooling demand within the London urban heat island

In London, the urban heat island increases the average and peak air temperatures

which in turn affect the demand for heating and cooling. To assess this, the simultaneous

hourly air temperature in London has been measured continuously for a

year at 80 locations, on a radial grid covering an area of 500 square miles. These

have shown that central areas of London are signi?ficantly warmer than the surrounding

areas (2 K warmer over the year). The measured data have been used

as input to a thermal simulation model to assess the heating and cooling load of

a standard air-conditioned of? office building positioned at different locations within

the heat island. It is found that the urban cooling load is up to 25% higher over

the year, and the annual heating load is reduced by 22%. Minimum CO2 is emitted

at a rural location. The net rate of increase of CO2 with temperature is found to

be 2.8%/K.