3 ms·

It’s cheaper to use a gas-powered water heater, right? I assume that’s because it’s also more efficient?

ajross 8y ago
No, it's because gas is (if your property is plumbed for it, obviously) cheaper to produce and transport than electricity for the same amount of heat energy. It doesn't make sense to talk about "efficiency" for heating itself -- energy is energy. I don't know whether it's more "efficient" in the sense of transport losses or not, my guess is it's a wash. Obviously gas inherently involves digging carbon out of the grown and throwing it into the atmosphere, though, so there's that to think about.
- opencl 8y ago
  For a lot of people the choice is between heating with gas and heating with electricity produced by burning gas- obviously using the gas directly for heat is much more efficient in this case because you are skipping the generation and transmission losses.
- zAy0LfpBZLC8mAC 8y ago
  Yeah, it is a lot more efficient, primarily due to conversion losses. A gas powered power plant loses about half of the energy fed into it as gas to waste heat, whereas a gas heater has essentially 100% efficiency. Also, no, gas does not inherently involve digging carbon out of the ground, you can produce methane in bio reactors or via electrolysis from electricity (see https://en.wikipedia.org/wiki/Power_to_gas https://en.wikipedia.org/wiki/Power_to_gas ), which is another method of storing surplus electric energy, either to be converted back later with a gas turbine, or to be injected into the natural gas grid.
rb808 8y ago
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.

No, it's because gas is (if your property is plumbed for it, obviously) cheaper to produce and transport than electricity for the same amount of heat energy. It doesn't make sense to talk about "efficiency" for heating itself -- energy is energy. I don't know whether it's more "efficient" in the sense of transport losses or not, my guess is it's a wash. Obviously gas inherently involves digging carbon out of the grown and throwing it into the atmosphere, though, so there's that to think about.

opencl 8y ago
For a lot of people the choice is between heating with gas and heating with electricity produced by burning gas- obviously using the gas directly for heat is much more efficient in this case because you are skipping the generation and transmission losses.
zAy0LfpBZLC8mAC 8y ago
Yeah, it is a lot more efficient, primarily due to conversion losses. A gas powered power plant loses about half of the energy fed into it as gas to waste heat, whereas a gas heater has essentially 100% efficiency. Also, no, gas does not inherently involve digging carbon out of the ground, you can produce methane in bio reactors or via electrolysis from electricity (see https://en.wikipedia.org/wiki/Power_to_gas https://en.wikipedia.org/wiki/Power_to_gas ), which is another method of storing surplus electric energy, either to be converted back later with a gas turbine, or to be injected into the natural gas grid.

rb808 8y ago

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.