How can factories reduce thermal pollution?

Thermal means 'temperature' and 'environment' means that which surrounds you. Temperature would include the ambient heat of the air, hot/cold surfaces and sources of thermal radiation.

Thermal pollution is usually caused by Man's production and use of energy or by Man's urban conurbations. There is little that can be done to reduce this form of pollution. However, thermal energy radiates away very quickly and Man's direct contribution to the heat/cold of the environment is minimal. It is greenhouse gasses that are causing the biggest thermal pollution but this is an indirect means of thermal pollution of the planet.