high-energy vs energy

high-energy is not a noun while energy is a noun.

Word	Noun	Adjective	Verb	Adverb
high-energy	No	Yes	No	No
energy	Yes	No	No	No

high-energy (noun)	energy (noun)
	forceful exertion
	an imaginative lively style (especially style of writing)
	enterprising or ambitious drive
	(physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs
	any source of usable power
	a healthy capacity for vigorous activity

high-energy (adjective)	energy (adjective)
of or relating to elementary particles having energies of hundreds of thousands of electron volts
vigorously energetic or forceful
providing a relatively large amount of energy upon undergoing a chemical reaction