London has the largest heat island in the UK and
there is considerable interest in determining its
characteristics so that strategic planning can be
properly informed. In the temperate climate of
England, an urban heat island (UHI) can be both
beneficial and detrimental – reducing the heating
energy used in the wintertime, and increasing the
cooling load in the summer. Both effects are very
strong, and knowing the balance of the UHI effect,
both city-wide and for individual buildings, is
an important goal of heat island planning. As part
of achieving this goal for London, its UHI has
been reassessed in greater detail than hitherto
