Assertion: water heater's energy cost | /r/CapableOf | mean having free hot water
Facets:
value: for years
type: TEMPORAL
value: essentially
type: MANNER
Source sentences:
text: And solar water heaters last between 15 and 40 years--the same as conventional systems--so after that initial payback period is up, zero energy cost essentially means having free hot water for years to come.