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Comment by ageitgey | Hacker News Reader

The context is that electric cars are flying off the shelves in the UK now, so the argument is that the subsidy money could be spent better elsewhere.

Of course some of that could be driven by the fact that it currently costs about 1/10th the price to fuel up an electric car vs. a petrol car (at least in London).

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> it currently costs about 1/10th the price to fuel up an electric car vs. a petrol car

Can you provide some data for that claim. Are we talking cost per mile travelled eg like for like?

I think it's closer than that?

Very roughly, UK prices are ~£0.2/kwh electrity and ~£2/litre of petrol. Per mile I make that £0.2 for petrol vs £0.045 for electric. Although you could probably get to the 1/10th figure if you always charged on the super-off-peak EV tarrifs.

Where are these places that give you massively discounted electricity at night?! Done away with around here many years ago… I wouldn’t rely on them always being there - obviously especially if everyone starts charging cars at night as it will cease being off peak and the reason for the lower price will be eroded.

There are multiple electricity providers in the UK currently that have "EV tariffs" where they give you substantially discounted overnight/off-peak rates in exchange for a slightly higher daytime rate in order to encourage overnight charging. Often up to a maximum specified number of KWh per cycle.

In previous times they used to offer a tariff called economy 7 which worked in conjunction with so-called storage heaters. They would charge during off-peak times and provide heat during more active hours. (disclaimer, I've never lived in a property on such a scheme but definitely saw a few in my student days)

Octopus (https://octopus.energy/) do 7.5p/kwh 00:30-04:30. I haven't used it, though, no idea if there are catches.

They are becoming more common here in the US. Although the one that I see most is more like a 3-4 hour peak period with very high rates and lower rates the rest of the day.

It's common in france due to the amount of nuclear

Assuming 7 pounds / gallon and 30mpg, a gas car would cost 23p per mile. Assuming 28.2p/kwh and 300wh/mi that comes out to about 8.5p/mi (figures pulled from Google for London, no idea if they're accurate, I'm in the US). In my experience that 300wh/mi is generous (my 2022 model y is usually closer to 350wh/mi in the summer driving downhill with the wind at my back and up to 450wh/mi in the winter). In any case, it doesn't seem to be anywhere near 1:10.

Do you drive like a maniac? Even here in Texas where you need to run the a/c full bore most tesla drivers see 250-300wh/mi.

No, and I'm actually worried that I got a shit battery. It also charges at max 60kw. I just drove from Illinois to Denver and we got an average of ~350wh/mi (we had the A/C on but we tried to moderate it to save battery).

There are charging losses to take into account as well. I think my gross is closer to 300 wh/mi lifetime than the 260 or so that the car reports.

My figures were not gross, sadly. :(

Energy pricing doesn't have to be constant - there's tariffs available which have cheap overnight electricity (eg Octopus Energy) - if you sign up now it's something like 7.5p/kWh, but some older contracts have it at 5p/kWh. You pay more during the day, but if you're charging a car a lot then it works out cheaper overall.

Looking at this, which has petrol costs from a month ago, it seems possible, although ⅛th is more realistic.

With today's price it would be 16p/mi for petrol. Their optimal May electricity price gives 1.88p/mi.

https://www.whichev.net/2022/05/13/is-it-cheaper-to-drive-an...

I pay $0.07 per kwh in Portland, OR. My Tesla Y gets roughly 3 miles per kwh. So 30 miles for $0.70.

At $5/gal and 20mpg, you'll pay $7.50 for 30 miles.

Cost per mile driven. 1/10th cost is on the more favorable end of the spectrum, but it's achievable if you can charge at home using an off-peak tariff. The ratio depends very much on what petrol MPG you compare it to.

It would be better spent on e-bike subsidies. They are a far more sustainable electric vehicle and have the added benefit of killing traffic.

That's a very London-centric view. An e-bike wouldn't be particularly useful in Devon.

It certainly would. One can get a lot further and move more things on an ebike compared to on a bicycle.

Not to forget the advantages of ten times less road maintenance, ten times more throughput, ten times less parking requirements, more social contact, ten times less energy consumption than an electric car, and on and on.

The main thing I've noticed here in slightly hilly Leuven, Belgium, is that so many more people I would never have seen on a human powered bike will actually use ebikes.

If you're a believer in government steering citizens to make the right decision, stimulating ebike use certainly makes sense. If in doubt, you might want to think about the war going on with one of our main energy suppliers.

More than 25% of the UK population lives in the five largest metropolitan areas, with the London urban zone being almost 15% of the UK population. Subsidising e-bikes and electrified public transit for those areas would be the most efficient and highest impact use of those funds for climate change mitigation.

Out of interest, how so? E-bikes are very popular in the Swiss countryside.

I would have thought an e-bike would actually have more use in Devon, than in a relatively flat city like London.

True, but don't more people live in London than in Devon?

I imagine a government would want to prioritize the highest impact action.

London already has excellent public transport. Devon has a bus on Tuesdays and they can't afford to put diesel in it.

Why would electric bikes be bad in Devon, though? Geography?

Practicality. They'd be fine for leisure, but not for travel to work if you live outside of Exeter and maybe some other big cities. The population is much more spread out than in larger urban areas. Most people live in smallish towns and villages and commute to work in urban centers (public transport is not good). Either that or they're agricultural workers who need cargo capacity and for whom ebikes would be useless. Also useless for famliles with children who go to school in another town or village. Plus, totally useless in the winter—the winter roads around here and Cornwall are bad enough when you have an SUV.

The cost you quoted can’t be right. I would like to see a quote for that. More importantly electric cars still cost a lot more to acquire and the vast majority of sales are ICE cars.

Ending subsidies seems counterproductive.

He's right but it's only in optimal condition where you can get cheap rate electricity. Driving in London is very efficient for EVs, you can hit 5mpkWh with ease since traffic is so bad. To cover 100 miles you only need 20kWh, at 5p/kWh off peak charging it's £1/100 miles. Equivalent petrol/diesel at £1.9/l and 55mpg is about £15/100 miles.

For public charging the rate is several times more than 5p/kWh, equalising the numbers somewhat.

It's not, it's about half as I did this exact calculation a couple of days ago in a new car discussion with my partner (charging works out to ~£0.49 per 4 miles, we're currently ~£1.05 per 4 miles for a reasonable mpg car driven primarily urban crawl)

though note that thats retail charging, home charging is half that (about £0.25p per 4 miles)

I suspect the issue is more that car companies can't make enough EVs for demand. I recently had a similar problem and ended up with an ICE car to avoid year+ wait times

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