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Electrical cars are very much promoted for a sustainable future, because they do not rely (directly) on fossil fuels. In the meantime, most of the electricity is produced with fossil fuels, such that electrical cars actually are less efficient from an energy standpoint than when the energy of the fossil fuels are used in a direct way. However, I understand that within a future where all energy is produced in a sustainable way, electricity is 100% green and electrical cars are too.

But, the same argument goes for electrical heating. Electrical heating is very much discouraged, because they are not green. However, creating heat with electricity is actually quite efficient. Now, electrical heating is less efficient than heating directly with fossil fuels; but in a world where all energy is produced in a sustainable way, electrical heating will be 100% green.

So, two times the same story, but a completely different general standpoint. Where am I making an erroneous reasoning?

One possible reason I got come up with myself, is that there is not much room for improvement in electrical heating technology, such that we can just wait with using electrical heating equipment until energy is produced in a sustainable way. On the other hand, it is advantageous to promote electrical cars, because there is much room for technological improvement there.

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    I suspect your question is very local. Where are you? Where I live electrical heating is very much encouraged and where I used to live the government will pay you to remove fossil burning heating and replace it with an electric heat pump. For that matter, I don't know of anywhere that subsidises electric cars. Australia is only just moving away from huge subsidies to fossil cars. If you are just talking about advertising... cars are advertised much more than heaters, regardless of type. – Móż Oct 28 '15 at 22:09
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    "electrical cars actually are less efficient from an energy standpoint than when the energy of the fossil fuels are used in a direct way" - no. Not unless your electricity comes from diesel generators. – EnergyNumbers Oct 28 '15 at 22:16
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    @Mσᶎ One example of a semi-subsidy: electric cars are exempt from the London congestion charge. – gerrit Oct 29 '15 at 10:56
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There are several reasons why a policy of encouraging electric cars, but discouraging electric heating, might make sense. I can't answer for the specific case of Belgium, which currently has some unique problems in meeting electricity demand, but some combination of the below motivations may apply.

Industrial policy

Electric heating is quite a mature technology now. On the other hand, electric cars are not. So an active industrial policy would encourage the uptake of the immature technology, but not the mature one.

Transport, urban, local environment policy

Local air pollution from gas boilers tends to be very low. However, local air pollution from cars is very bad. In addition, they're noisy. Electric cars solve these problems, so encouraging them can be a positive intervention for transport, urban or local environmental policy.

Electricity capacity

If the building stock is not super-insulated, and local climate requires a lot of heating, then electrical heating would place a very high burden on local electricity distribution network capacity, on transmission capacity and on generation. That's because any building can get electric heating at very low investment, very quickly: it's as simple as going to the shop and buying a resistance heater. Cheap to buy, easy to install. And a very very high rate of electricity consumption in winter.

Whereas buying an electric car is different. It's a high capital investment. You need somewhere to park it, and a licence to use it. And, except for extreme cases, the rate of electricity consumption is pretty low, and not particularly seasonal. So even with rapid take-up, there'd be much less stress on the electricity system.

Competing heating supplies

If a country has a domestic non-electric heating supply chain, but not a domestic non-electric vehicle supply chain, then encouraging electric vehicles but discouraging electric heating would protect domestic industries.

Net energy demand

Some countries (France for example, as well as EU energy-efficiency targets) have particular targets on reducing the rate of total energy consumption. Internal combustion engines are terribly inefficient: well-to-wheel it's 20% or so. Whereas for electric vehicles, even if the electricity is powered by coal, they're more efficient than that. So switching from fossil cars to electric would cut primary energy consumption; whereas switching from gas heating to electric would be likely to increase primary energy consumption.

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The first part of your question is about where pollution happens as much as about pollution reduction. Cars emit pollution where people are, while electric generators can be built further away from most people. That reduces the (human) impact of the pollution. Normally fossil burning plants are built outside cities, often close to the fuel source because it's cheaper and more efficient to move electricity than coal. Oddly enough hardly anyone wants to live next to a coal fired power station (see also: wind farm syndrome).

A secondary factor is that it's much easier to filter the pollution coming out of a few big fossil electricity plants than to filter every single car. And it's easier to enforce, too, if the government is interested in doing that - testing the output of a few plants is easier than testing every car.

Secondly, the main reason why electric is discouraged is that it's not self-contained, so people living where the grid is unreliable or unavailable can't rely on electric heating. Fossil fuel heaters typically have a large fuel reservoir on site so can run for days or weeks after a storm disrupts the electricity supply. Where big storms are common in winter households need to be fairly self-contained to survive them.

As far as improvement in technology goes, over the last decade the performance of electric heating systems has increased significantly (interesting history pdf). Best of class coefficient of performance (CoP) has gone from 3 to 5. In New Zealand there were subsidies for people switching from fossil or resistive heaters to heat pumps for this reason - not just less fossil burning, but less electricity use overall.

Building technology is an odd mix, where the actual knowledge and materials for very efficient houses are readily available but the housing being built doesn't use it. So it's sort of correct to say that there's not much room for improvement (focus on the technology), but it's also true that we could get a dramatic improvement very easily if we wanted to (focus on the houses we have).

It's worth noting that even though NZ generates 70%+ renewable electricity (mostly hydro) they still have cheap off peak power rates because that evens out demand on the grid. If they can persuade people to power hot water storage and thermal mass heaters overnight the peak load in the evening drops. So they do that, as it's cheaper that massively increasing the size of the grid.

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    I've lived in rural Ontario for 23 years, with electrical heat. In that time we've had tons of power failures, but only one where we had to use our fire and woodstove for heat - Jan 1st 1999. The house holds heat well. Places with iffier electricity tend not to have cold winters. – Kate Gregory Oct 29 '15 at 0:23
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    Interesting. I keep reading about grid failures during winter storms in the US and have seen people say that's why electric heating needs a backup, or that they use fossil fuel for that reason. – Móż Oct 29 '15 at 0:54
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The biggest reason is why it is being used. Converting combustion heat into electricity and then converting electricity back into heat is highly inefficient. Better to just create the heat by combustion on the spot.

Cars however don't need to produce heat, they need to provide motive power. Electricity is a transportable way to store power and and deliver that power wherever you are without creating a huge amount of waste heat and a blanket of pollution wherever you go.

You can filter your pollution at power plants much better and more efficiently that trying to do so on a small power plant like a car engine, and power plants centralize a lot of the work involved in keeping that power "cleaner", I.e. Filter changes and waste, heat recapture, carbon collection, etc etc etc.

  • Thanks for the answer! However, power plants also create their electricity by converting the heat into motion by means of a turbine, which is then converted to electricity, and then again converted to motion in the electric car. This seems to yield the same argument as you have against electric heating. Moreover, I guess that the filtering of the pollution also occurs less efficiently when heating your house? – BNJMNDDNN Jan 28 '16 at 19:38
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There are a couple of good answered already, but here's another perspective (who said a question can only have one right answer!).

In a possible future world where electricity generation is plentiful and carbon-free, then it will make sense to fully electrify both transport and heating.

We do not yet live in that world. In most countries electric heating is less efficient, in terms of primary energy consumed, than gas or oil (except perhaps with heat pumps, which might sometimes win). However, on many countries' existing generation mixes, electric cars are already more efficient than petrol or diesel ones. This is because fossil fuel power stations are generally more efficient than vehicle engines, by a sufficient margin that (together with some help from nuclear and renewables) this makes up for transmission and conversion losses.

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