Heat Engines are only 20% efficient at converting raw energy (oil) into work.

First, any process that converts thermal energy into "work", the answer is "easy".

The self-contained power unit converted nuclear energy to light with 99 percent efficiency.

Is it possible to do the reverse and convert energy into matter?

Some elements in a circuit can convert energy from one form to another.

They convert solar energy to electricity for operating the observatory.

An engine is a device that converts potential energy into mechanical work.

An electric fire is 100% efficient in terms of converting electrical energy into heat.

There are forces in nature, such as gravity, that exist without converting energy.

"I'm trying to develop a machine which will convert energy into matter," Tom explained.