> gas clothes dryer is more efficient and interestingly, less fire risk than electric
A regular electric dryer is 100% energy efficient, just like an electric resistance space heater. A heat-pump electric dryer can be 2-300% "efficient" (really COP) because it uses a heat pump.
A gas dryer is strictly less than 100% efficient - because like with any combustion device, some portion of the fuel is unburned and is sent out the exhaust/flue. Even the most expensive gas condensing modulating furnaces are only in the 90-97% combustion efficiency range.
Gas dryers are usually more time efficient though. They achieve such high temperatures (thanks to combustion) that they dry clothes 50% faster. And because gas is cheaper than electricity, they are cheaper to operate. The operational energy cost advantage vanishes when compared to heat pump electric dryers, however.
Electric dryers aren't 100% efficient if the source is the usual gas/coal/nuke/etc steam plant because the plant itself is only ballpark 50% efficient at converting the heat->electricity, then you take a percent or ten in transmission losses/etc. So, if the choice is pump the gas to a combined cycle gas plant, burn it, transmit the electricity to a resistivity heating dryer vs pump the gas directly to the dryer and burn it, the gas dryer will generally win.
Using a heat pump returns much of what is lost, but on balance in most places its sorta a wash. To be specific you have to look at the whole picture including the energy source, which requires actually picking a location/city and a particular product. And even saying maybe 100% of your power comes from PV+Wind (yah righ, haha) if you really want to lower the footprint the best plan is just to hang your cloths outside.
Yes heat pumps are more complicated. Likewise LEDs are more complicated than incandescent bulbs. Condensing furnaces are more complex than gravity furnaces. And nothing is simpler than a clothesline.
Higher efficiency usually involves higher complexity (EVs being an exception, although batteries themselves are pretty complex at tiny scales).
What's also great about heat pump and other condensing type dryers is that they are ventless. With a regular vented dryer, each time you run it you exhaust several thousand cubic feet of indoor conditioned air, which gets replaced by outdoor unconditioned (hot, cold, or dirty) air due to the depressurization of your house.
One way or another, you pay for reconditioning that air.
Depending on how much you do laundry, your local climate, and the price of energy, a ventless dryer (which can only be electric, naturally) can save you a lot in energy costs by avoiding that air exchange.
A regular electric dryer is 100% energy efficient, just like an electric resistance space heater. A heat-pump electric dryer can be 2-300% "efficient" (really COP) because it uses a heat pump.
A gas dryer is strictly less than 100% efficient - because like with any combustion device, some portion of the fuel is unburned and is sent out the exhaust/flue. Even the most expensive gas condensing modulating furnaces are only in the 90-97% combustion efficiency range.
Gas dryers are usually more time efficient though. They achieve such high temperatures (thanks to combustion) that they dry clothes 50% faster. And because gas is cheaper than electricity, they are cheaper to operate. The operational energy cost advantage vanishes when compared to heat pump electric dryers, however.