Yes gas is cheaper measured in btu/$. An electric heat pump could be more efficient, but that's not normal for domestic hot water heating. It can be big deal f

Yes gas is cheaper measured in btu/$. An electric heat pump could be more efficient, but that's not normal for domestic hot water heating. It can be big deal for the environment. Compare "green" solar to heat water is much better than fracking your groundwater and creating greenhouses gases. If the electricity comes from coal burning, gas could be less worse.