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Comment by rcMgD2BwE72F | Hacker News Reader

What's more widely distributed than electricity?

Delivering high voltage to recharge the amperage these batteries need is a whole different grid in remote areas to delivering 240v for light bulbs and fridges.

Separately Norway is one of the richest countries on the planet thanks to its offshore oil. Their sovereign fund dwarfs Saudi Arabia in comparison so maybe they currently can cannibalize that revenue to build a supergrid.

China is building an ultra high voltage direct current supergrid to accommodate future EV needs (using primarily coal as a power source). I don't see this happening anywhere else?

http://www.economist.com/news/science-and-technology/2171432...

I don't know what the situation is in Europe, but in the US farmers use a lot of power. They have welders and other such tools that can draw 50 amps or more. The motors for their drying fans are drawing 20 amps each (and several of them can run at once). Note that the above amp figures are at 240 volts just like power in Europe, not the lower 120 we use for lights and fridges.

continuous draw for hundreds of thousands of batteries is vastly more than this example

What is the application for hundreds of thousands of batteries on a farm?

Denmark doesn't really have "remote areas" by the standards of large countries.

Here's a map of the high voltage power grid. I don't think anywhere is more than 50km from a transmission line.

https://en.energinet.dk/-/media/9160AAB5C484432399767220B78D...

The increase will be gradual, and no doubt the power grid company is already planning for it.

You could use train/tram/trolleybus grid for adequate voltages.

> Delivering high voltage to recharge the amperage these batteries need is a whole different grid in remote areas to delivering 240v for light bulbs and fridges.

If they have 240v outlets, that's half the battle. That is around 31 miles per hour of charge, from a standard outlet (although you have to make sure your wiring is good) without any extra infrastructure.

This may not be sufficient for a cross-country drive across the continental US, but for most european countries? You can drive 300 miles and charge overnight even with no fast charging at all.

Compare this with setting up gas stations (digging underground to install the tanks, logistics to keep them topped off, etc) and gasoline starts to look quite insane. It's just that we have this existing infrastructure built over a century that we take for granted.

No need for a separate grid to deliver high voltage even in rural areas, the overhead or underground wires are between 4KV to 30KV anyway. There is a transformer to step it down to the end use voltage, whatever that is, eg 240 or 400.

The guys who run the British National Grid disagree that the grid needs major changes: http://fes.nationalgrid.com/media/1264/ev-myth-buster-v032.p..., http://fes.nationalgrid.com/media/1253/final-fes-2017-update.... The Norwegians aren't predicting the need for supergrid either: http://publikasjoner.nve.no/rapport/2017/rapport2017_77.pdf (sorry it's in Norwegian and too big for Google and Bing to translate).

Find me high-voltage high-amperage connections on the side of the freeway though.

Denmark is small, flat and relatively populated and rich.

Probably you're never far from a high voltage transmission line.

That doesn't cost much (far less than a gas equivalent) and can be installed alongside highways within weeks.

If people purchase EV _en masse_, they'll have charging stations everywhere. There's no egg/chicken problem here.

Worldwide, transport energy use is about 150% total electricity use — 30PWh/y vs. 20PWh/y.

I’m not saying we can’t upgrade production (I’m actually significantly more optimistic than the best case IAE estimates), but it’s not as trivial as just installing some new wires and transformers.

I'm curious, is that only non-point-to-point personal transportation or does it include all forms (e.g. ocean shipping, rail, public transport)?

That’s very good point, looking at my source the answer appears to be “everything”. I will try to remember that in future.

However, my point is only that we will need non trivial increases in electricity production, rather than any specific number. That point still stands.

You could have a solar farm and some batteries close to each stations. It's not trivial but it isn't a bottleneck either.

When I ran the numbers for the USA, it was something along the lines of adding a 1m wide strip of normal efficiency PV alongside the entire length of the interstate network. I’ve not looked at the size of any other highway system relative to population density but I do know that Denmark gets less sunlight than the USA average.

Like I said in my original comment: I’m optimistic, I just don’t think it’s trivial.

To put it another way, I think it’s something that requires a government rather than being achievable purely with the private sector. That might mean just incentives and template plans, or it might require government to commission things, but it’s that sort of scale.

Yeah, so, the first thing to know about that is ICE is ludicrously inefficient. Spinning all that metal at variable speed with tiny explosions is, unsurprisingly, not the best way to turn high density fuels into energy. The thing ICE had on its side is the energy density, on other metrics it's a bad deal (hence why free charging for EVs is affordable)

So if you have 400MW of ICE cars you don't need 400MW of electricity to replace that, something more like 80-100MW is more like it IIRC. The infrastructure build cost isn't zero, but it's much less than this 150% metric suggests.

Getting some rough numbers from Wikipedia it looks like most common new cars are sitting around 35% thermal efficiency. I believe a formula 1 engine achieved 50% thermal efficiency recently but the cost of that is obscenely high. Where as electric motor efficiency easily hits 90%+.

"ludicrously inefficient"

No, they're not. They're, as implemented in a car, a ludicrous example of engineering compromises.

Put a hybrid drive methane spark-ignition high compression engine and you'll have similar CO2 emissions from a e-car powered by a thermal plant (the vast majority of our power). It'll cost as much as a Tesla too.

It's also quite inefficient to convert hydrocarbon energy to mechanical energy to electrical energy to chemical energy back to electrical energy and then back to mechanical energy, as an electric car does. ICE goes straight from hydrocarbon to mechanical. It would not surprise me if it's more efficient, though I don't know.

They're already common along the highways in DK (incl. a few Superchargers)

Map: https://www.google.com/search?client=safari&rls=en&q=tesla+s...

Gasoline

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