Eli5 if electric vehicles are better for the environment than fossil fuel, why isn’t there any emphasis on heating homes with electricity rather gas or oil?
In: Physics
A furnace turning fuel to heat is much more efficient than a car engine turning fuel to go power. Therefore, the gains aren’t as evident from going all electric to heat your homes.
Electric heaters are 100% efficient. However, electricity generation is far less than this.
Burning combustible materials for heat is much more efficient than burning them for electricity.
That said, if your electricity comes from renewable sources, it’s better to use electricity. It’s best to use heat pumps rather than resistive heaters (e.g. space heaters), since those can move more heat than the energy they consume (for every watt of electrical power consumed, they can move 2.5-4 watts of heat power from outside to inside).
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There is, but it’s slower and quieter. You can for sure find people talking about how especially switching to heat pumps will be an important part of limiting climate change. Because they’re just moving heat around instead of creating it, heat pumps can (sort of) be more than 100% efficient. Or at least, you can use 1000 watts of electricity to bring 2500-3000 watts of heat inside.
It’s slower and quieter because cars get replaced much more quickly than houses and apartment buildings do, and probably more quickly than residential climate control systems do. Also, retrofitting heat pumps into homes that weren’t designed for forced-air heating/cooling can be expensive.
In 2040, the housing stock in the US is overwhelmingly going to be the same houses and apartments we have right now, and at least a substantial minority of those places are going to be using the same heating/cooling systems they are right now. But in 2040, the stock of cars driving around will be mostly cars built in about 2030. (unneeded word deleted)
The useful output of a car engine is kinetic energy (to rotate the wheels), and these engines can transfer ~30% of their input energy (from the gas) to motion. The rest is lost as heat.
The useful output of a furnace is heat, this means that what was previously wasted is actually useful.
So there isn’t too much of a difference in efficiency between electricity and gas heating. The biggest impact to overall efficiency for heating a house is making sure it is insulated as well as possible, so that heat isn’t lost to the outside.
It is done. In French alps they use electricity since the 70s at least, but they use nuclear plants to make electricity.
The new trend is to make electricity on your roof with solar panels (you don’t lose power due to transporting it. Electric lines can lose up to 3%) and tre second step is to use heat pumps instead of electric heaters.
Heat pumps are a lot more efficient than heaters, and they also provide air conditioning in summer.
if you are in the USA, oil and far are so cheap that there is less drive into changing system.
In Europe it is a net gain, you save the planet AND save money.
> why isn’t there any emphasis on heating homes with electricity rather gas or oil?
Isn’t there? Maybe it varies by where you live, but I’ve seen plenty of recommendations to use heat pumps for heating (those operate on electricity). More so than recommendations to drive electric car.
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Electric vehicles aren’t just better for the environment, they’re way more fuel efficient.
When your cars using fuel, the primary byproduct is thermal energy. But your car doesn’t want thermal energy, it wants kinetic energy. So with fossil fuels, a lot of your engine is designed around turning that thermal energy into kinetic energy, and a lot of efficiency is lost.
With an electric car, the energy is applied much more directly.
In a furnace, you have the opposite effect. You want the thermal energy, so there’s no conversion. Since electricity itself doesn’t produce my thermal energy, it’s heating a coil to a temperature and then using constant energy to maintain that temperature.
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