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Comment by Gwypaas | Hacker News Reader

He is not contradicting himself. You have to remember the awful efficiency of thermal engines.

Primary energy demand will decrease because you do not lose 70% of the energy by simply cooling it like in steam turbine used by nuclear power plants or car engines.

On the other hand, electricity usage will increase because you have now replaced your 30-40% efficient engines with 90+% efficient engines, but from a different source. That barely have any losses from the primary energy input.

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Since we should keep the oil in the ground that current thermal engines uses, the energy input will be from a different source when we change from burning oil to electrical engines. The primary energy input should be from the wind, sun, elevated water, nuclear bonds and geothermal.

The change from 30-40% efficient engines to 90+% efficient engines is if we burn the oil in a power plant. It is an improvement, but not a sufficient big one compared to actually keeping the oil in the ground.

You basically can't get 90% efficiency from burning oil in a power plant. E = 1 - Cold/Hot, where cold ≈ 300 K and hot ≈ 1300 K (gasoline-air fire), giving theoretical maximum efficiency of 77%. In practice much lower, what I've seen is just over 60% even in the best combined cycle power plants.

If you use some really high temperature chemistry, you can get to 5260 K from dicyanoacetylene in oxygen, which is 95%, but not gasoline. And dicyanoacetylene is a bit explody.

True enough, but I’m hopeful for an energy-abundant future where we figure out how to make solar, wind, nuclear, and batteries cheaply and at scale. Imagine what we could do if energy efficiency didn’t trade off against carbon output. We wouldn’t have to replace all our appliances with something slightly more efficient (and less maintainable) every so many years. And the resources it takes to do that could be redirected elsewhere.

Everything else is getting cheaper, at an exponential rate, but nukes are getting more costly.

> We wouldn’t have to replace all our appliances with something slightly more efficient (and less maintainable) every so many years

We are forced into poorly built, unrepairable appliances through a market failure.

Failure of consumers to spread the word about appliance repairability. Fraudulent forgery of consumer reviews by manufacturers.

Failure of the housing market driving the repair technicians out if business - its cheaoer for someone in china to spend 10 hours building new washing machine than for someone in uk to spend 2 hours fixing it.

In some cases, a deliberate subversion of the spare parts market by manufacturers.

There is not a grand plan to improve efficiency and solve clinate change.

Sure, there’s not much incentive for manufacturers to develop reliable appliances, because people just shop based on price and features. Once of the only constraints is government regulations which ban the old, less efficient designs. Take away those regs, and manufacturers who don’t want to pay for R&D can churn out those simple designs again.

> because people just shop based on price and features

But thats all they can do - suppose I want to fins out if a Samsung phone is more reliable than Fairphone or Huawei - how would I find out? Will their salesmen tell me the truth? would customer support? Does their marketing department publish mean time between failure or statistics for repair?

There is very little hard data where anyone took thousands of appliances and measured their reliability.

I guess part of the problem here is that everything changes so frequently. If technology moved so slowly that generational change in craftsmen was the major source of a change in quality, then you could actually use word of mouth and other external sources of information. Nowadays, the experience of a year or two ago really doesn't necessarily tell you much about the quality of the products that are available now.

The Linus Tech Tips labs is already doing wonders in their market niche, I really really hope it all works out for them.

They've built up significant trust with their community, they're not perfect, but close enough that I'd trust their reviews blindly in domains where I'm not informed enough already. (Everything except their dabble into datacenter storage, virtualization and networking)

Thanks for that

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