Impervious surfaces collect solar heat in their dense mass.

Come winter, the coat would be changed to absorb light and collect heat... but at the moment, the windows were still on summer settings.

Passive solar heating relies on the design and structure of the house to collect heat.

At the first stage, a heat exchanger collects heat from the air outside to use as energy for the refrigerant.

In winter, it collects heat from outside and pushes it inside.

The opening faced the fire to collect heat, and could also be closed tight if necessary.

The building also collects heat from computer equipment and recycles it throughout the structure.

Solar energy, for example, can be gathered in an active way to collect heat and produce electricity.

The open atrium faces south to collect heat from the sun, an example of passive solar building design.

Solar thermal energy is harnessed by collecting direct heat from the sun.