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Comment by caymanjim | Hacker News Reader

I'd be surprised if power use weren't hitting record highs every single year. More people, more EVs, more more industrial automation, more data centers, more new construction with climate control, and on and on. Efficiency gains can't possibly be enough to offset overall growth.

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The switch from incandescent to CFL and LED bulbs was a big jump in efficiency, and that one was pretty easy to implement at the consumer level. There should have been a modest reduction in power usage with the switch from CRTs to flat panel displays as well. However, that was low hanging fruit and there aren't too many other places where we are going to see that kind of jump.

Maybe some kind of powerful heat pump based kitchen oven? The heater coils they currently use are basically unchanged since the invention of appliances, but it's hard to imagine what a more efficient replacement would look like with foreseeable technology. Some sort of induction oven where you always have to stick your food in an insulated metal box before sticking it in there?

Maybe a hot water heater that uses a heat pump? Maybe it would have two tanks and you pump heat from one tank into the other, making your cold tap super cold at the same time?

There just aren't a lot of places left for your typical household to save a significant amount of power. I'd love it if industrial users put more thought into power savings but that requires buy in from rich people and that's a lot harder to do.

What percentage of electricity usage was incandescent light bulbs?

It's hard to say, but the changeover was noticeable:

https://www.nytimes.com/interactive/2019/03/08/climate/light...

When you have a technology in very nearly every home in the country and used daily that you can replace with something a whopping 85% more efficient it adds up.

Ground to air heat pumps could increase efficiency for air conditioning (which in hot and humid states is probably the largest line item for electric usage). Part of the problem here is the install cost means you likely want to share the ground source piping with 4 or more homes, but we don’t really do small scale self governance (build or share things amongst a dozen or fewer households) in the US anymore.

There are heat pump water heaters already. I think people usually have them setup so that the excess cold air is either used to keep the building cool in hot weather or it's routed outside in cold weather.

The next low-hanging fruit improvement is community solar installations, or barring that, individual home solar installations.

Technically, things like better insulation are low hanging fruit in the sense that the technology exists and the materials for it are cheap, but it's incredibly labor-intensive, especially when retrofitting old housing stock.

Solar is much easier to retrofit onto a home than making a 50+ year old house well-insulated.

Maybe steam convection ovens are more efficient? I haven’t looked at power consumption, but it might be less since steam requires a lower temperature to work with. But people use their ovens so little that it might not matter much in the large scale.

Even if we were using substantially less energy overall, transitioning away from fossil fuels for heating and transportation is likely to result in using a lot more electricity.

I expect most modern countries are going to need to be constantly upgrading their power grids and power generation capabilities over the next few decades. Hopefully most of the new energy generation will be renewables.

Where do you think the electricity comes from?

The same place hamburger, bacon, and keebler cookies.

elves

It depends. Fossil fuels are still a major source, which needs to be replaced as soon as possible with something else (where "something else" probably means some combination of solar, wind, and nuclear).

What I'm saying is that in our long term planning, we shouldn't be thinking "we have X terawatts of fossil fuel production capacity so we need to build out X terawatts of non-fossil-fuel production capacity to replace it (including storage, as needed)" We should be thinking "We probably need ~2X terawatts of additional production because we're replacing fossil fuels for electricity generation in addition to transitioning to electricity-based heating and transportation."

EV's mostly charge at night when demand is low, so they should have an undersized impact.

We'll need more generation, but only about half as much more as a naive analysis would indicate.

Interestingly, energy use actually declined during the first year of the pandemic (I know for sure in the US, and probably globally). You can see it here for Texas, https://findenergy.com/tx/#overview , in the annual production graph, which is the state with the most production in the US. On a national level IIRC, it was approximately -4% from 2020 to 2021.

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