Word | Noun | Adjective | Verb | Adverb |
---|---|---|---|---|
free energy | Yes | No | No | No |
alternative energy | Yes | No | No | No |
free energy (noun) | alternative energy (noun) |
---|---|
(physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs | energy derived from sources that do not use up natural resources or harm the environment |