Tidal and direct heating from Trygve supplemented the sun's meager output.

The temperature of the surface becomes warmer than it would be if it were heated only by direct solar heating.

All forms of direct heating are a "low grade" energy use that can be achieved more economically, and with lower carbon emissions, by combustion processes.

It is primarily used to hold small quantities of substances which are undergoing direct heating by a Bunsen burner or other heat source.

As with direct heating, however, the ultraviolet mechanism is often found wanting.

A revolutionary system, as it did not use direct electrical heating.

There is molten salt storage, used in some direct heating solar plants.

Sharav is used for direct heating of the material.

Microwave radiation penetrates food and causes direct heating only a short distance from the surface.

Inside the body, though, direct heating isn't possible; some kind of noncontact method is required.