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Comment by delecti | Hacker News Reader

The global energy usage from crypto was in the ballpark of 120-240 TWh/year, but a couple figures repeated the specific 150 TWh/year figure, so I'll use that.

The US's annual gasoline consumption is 135 bn gallons (2021 figure). At around 20 mpg (random estimate because I have to pick something), that works out to 2.7 trillion miles. At 30 kWh/100mi (figure from google), that works out 800 TWh if every gas vehicle in the US was suddenly switched for an electric one, or about 20% of the US's annual electricty generation of 4222.5 TWh (2018 figure). Also, that's about 5x the global crypto energy usage, vs just America's cars. [Obvious disclaimers: some of those estimates are arbitrary and not perfect, but they're in the right ballpark, and we obviously wouldn't switch to electric cars overnight]

Crypto was bad because it didn't actually accomplish anything with that power usage, but it was a pretty small footnote on the grand scheme of things.

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If it is only 20% more generation, that seems pretty feasible. The widespread usage of air conditioners caused a greater increase in electricity usage than that.

As more and more people switch to Electric Heat (heat pumps i.e AC run backwards) off of NatGas more and more energy companies are pleading with people to turn down their heat in the winter and up in the summer as the grid can not handle it

For the first time I can remember, my power company was sending out Texts here in the midwest during that last Arctic blast telling people to use less electricity because the grid was over taxed.

Our National Energy grid is very very fragile.

That is such a misrepresentation. It has nearly nothing to do with heat pumps, it because there is a large amount of electrical resistive heating used in Texas.

Converting natural gas furnaces to heat pumps and replacing resistive heating with heat pumps, would not increase the total electricity usage at all. Last I looked 40% of heating in Texas was done through resistive heating, heat pumps would be 3-4x more efficient. There is current power devoted to resistance heating to run heat pumps for every home.

I was not aware that Texas is in the midwest... I am not sure what Texas has to do with anything here.

That said, no one isreplacing NatGas with Electric Resistive Heating, that would be crazy, NatGas is still cheaper in most cases for people north of say KY but there are alot of HeatPumps going in

I am unclear why you think replacing a NatGas heater with a HeatPump "would not increase the total electricity usage at all" that is just false, and I am not even sure why you would claim other wise, NatGas is not an Electric Fuel Source so when you change from a non-electric fuel source to an electric fuel source you will use more electricity. Now changing from Resistive Electric to heatPump would actually drop your electrical usage in some cases (above 0degrees anyway)

Around here it is not uncommon to have a HeatPump with a Gas "emergency" heater for when it gets too cold for the heatpump, as Electric Resistive is TERRIBLE and expensive. The problem is when that combo is sold normally it is wiht 80% furnances or they just leave the old furnace in place and just upgrade the AC/Heatpumpt

Not OP, but changing from natural gas heat sources to heat pump does increase your house electricity demand, but then that natural gas is no longer consumed. Natural gas is commonly used as the 'peaker' energy source today... so it's likely that you're just going to be burning natural gas at a plant somewhere else to power your heat pump in the peaky cold snap situation. Natural gas power plants are going to be more efficient than your furnace, unless you have one of the very modern furnaces, and the amount of gas needed to be burned and turned into electricity is going to be a ratio (3:1, 4:1...) lower than the natural gas needed to be burned to heat your house.

Overall that seems like a reduction in total emissions, since you're using less natural gas overall to heat the same amount. Yes, it increases power demand, but is also lessens demand on natural gas by a greater amount.

This could be a overall net negative if the power mix is heavily polluting (coal... etc), but largely we're moving away from that over time and it will only get better.

>Overall that seems like a reduction in total emissions, since you're using less natural gas overall to heat the same amount.

This just isn't the problem at all; it's obviously a problem, but not the constraint here. Fossil fuels let you store energy in a distributed fashion (e.g. cutting and stacking firewood for the winter), which is way better for handling peaks.

If too many people get burnt by oversubscribed grids in the winter, I would expect that the middle- and upper-class response will be propane auxiliary heating systems.

Natural gas doesn't really allow a consumer to store energy. Nobody has a tank to store natural gas next to their house. Yes, you can do that with propane... but it also now requires you to have a heating system compatible with propane (it's just a nozzle change for most NG units... but still, that's way beyond the capability of most homeowners to do).

The only thing that using natural gas to burn for a furnace (vs. using it for a heat pump) gets you, is that you need more natural gas generation plants and the infrastructure to handle the additional power on the system. On the other side of the coin, you have all the natural gas infrastructure to each house premise to maintain... which can leak, have issues, etc etc etc.

Texas has its own electrical grid separate from the rest of the US.

Why is every commenting about texas? No where in my comment did I mention texas, the closest was "texts" i.e SMS messages, not texas.

I do not live in texas.

it makes for a funny read. people are very passionate about your Texas errr Texts

I read Texts as Texas.

Anyways in areas where it regularly goes below 0F, the transition will not be smooth (but probably still necessary). Heat pumps that operate efficiently down -20F are just coming out and will be even more expensive than normal heat pumps. Also most residential energy usage in really cold areas are from burning natural gas, so electricity generation is quite low compared to warmer parts of the country.

Interesting to note that there is ~30kWh of energy in a gallon of gasoline, so the reason EV would only take 20% of US electricity consumption is that they are 5x more efficient (than the 20mpg gas figure used).

Indeed seems manageable.

I did not verify his figures, but his methodology was BEV efficiency, not the amount of energy in a gallon of gasoline. Electric drivetrains and cars are designed ground-up for efficiency to a degree that ICE cars are not, as well as the fact that something like 80-90% of energy in a gallon of gasoline is wasted (60-70% due to Carnot efficiency alone).

Crypto was 1/5th of the ENTIRE US CONSUMER TRANSPORTATION (BEV efficiency converted)????

That is an astonishing amount of electricity for something of so little value.

But anyway, to the larger point, I agree the grid impact is overblown, especially since we should be coupling consumer BEVs with home / business / warehouse / commercial solar.

The main thing your comment highlights for me is how much of a push we need for more sustainable methods of transportation in general.

There's always going to be people who will need to drive, but there's a hell of a lot of people who could be perfectly adequately served by strong public transportation.

>>but there's a hell of a lot of people who could be perfectly adequately served by strong public transportation.

Never going to happen for 80-90% of the US. It is neither economically feasible, culturally feasible, or practically feasible for most people in the US.

Work places are too spread out, homes are not located near workplaces, and there is no desire from anyone (my self included) to increase density.

I want less density not more, "walkable" cities only work if people actually want to live in a walkable city. Many many many dont

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