"The choice of building material is key in reversing the heat island effect, for it is the dense, dark-colored structures which attract sunlight and retain it for long periods of time. Concrete and lighter colored aged asphalt pavement with its naturally lighter aggregate colors, is ideal in its resistance of heat absorption.
Simply by choosing a material that is not black we can reduce the heat island effect and air conditioning costs can be lowered by as much as 8-12%, the intensity of air pollution lessened, and heat-related health problems prevented."
The above information is taken from the National Ready Mix Concrete Association