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Does that use a lot of energy?

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Re: Does that use a lot of energy?

#161

Post by toomuchtodo »

eru wrote: post #150
toomuchtodo wrote: post #138

Earlier quoted context omitted.

Lots of it is lost to heat with legacy fossil generation.

You have pretty much the same heat losses with nuclear, or anything else where you heat water to turn a turbine.

Nuclear is low carbon, it’s fine we lose heat to extract that energy versus stationary and mobile combustion generation, as there is no other effective way to extract that energy at this time.

Quantification of global waste heat and its environmental effects - https://www.sciencedirect.com/science/article/abs/pii/S03062... - Applied Energy Volume 235, 1 February 2019, Pages 1314-1334

* 49.3–51.5% of global energy use would end up as waste heat in 2030.

* Transport sector accounts for the largest (43%) recoverable waste heat in 2030.

Re: Does that use a lot of energy?

#162

Post by j16sdiz »

jwilliams wrote: post #28

It was genuinely a surprise to see how much relative energy petrol cars use (and shame on me - I'm an electrical engineer). I mean I think I knew it intuitively, but this simple chart blew my mind.

But that's not an apple-to-apple comparison.

Like, if you "save energy" by not driving a petrol car, you can't "use the same energy" on electric car, or lighting.. not even prower a generator.

They are not interchangeable.. But this chart encourage us to think them as the same.

Re: Does that use a lot of energy?

#163

Post by appreciatorBus »

djhworld wrote: post #55

I think stuff like this really crystalises how people misunderstand how much energy stuff uses. My parents for example sweat the small stuff and go around the house turning LED driven lights off to "save electricity" even though it would barely make a dent in their bill. Granted, they come from a time of incadescants burning 60-100w at a time so I can see why that habit might be deeply ingrained.

Yup. In my experience, average non-nerd folk very very little feel for this stuff. I suspect some believe energy consumption of phone vs car is basically a toss up.

Re: Does that use a lot of energy?

#164

Post by nomel »

eru wrote: post #152
nomel wrote: post #75

Earlier quoted context omitted.

Where I am at least, people using less power because power because power need to profit more, is wild . They literally had record profits the last few years, rather than being forced to lay down solar. I think power should be a global endeavor, not some local for profit business with complete regulatory capture that makes competition illegal. Yes I'm angry, because I pay more in electric than most anywhere in the wor…

> They literally had record profits the last few years, rather than being forced to lay down solar. I think power should be a global endeavor, not some local for profit business with complete regulatory capture that makes competition illegal. Sounds more like you guys should be lowering barriers to entry, not setting up a global non-profit cartel.

True. I suggested global because it allows for scale with copy/paste designs, where things like nuclear could actually become viable.

Where I am, we have a solidly aligned state government. There's no concept of consequences for anyone in power. They're paid by the local companies to pass laws to make competition legal. Some are investors. All corrupt. That's what you get with a solid political alignment.

Re: Does that use a lot of energy?

#165

Post by bethekidyouwant »

lokar wrote: post #142
noosphr wrote: post #127

Earlier quoted context omitted.

You charge your car at night. At night the sun doesn't shine. The mix is mostly coal or if you're lucky mostly gas. This is the type of bullshit I mean by doing real world calculations.

I charge during the day, from my rooftop PV panels. Over a year we are net negative on grid consumption.

This means you don’t take your car to work, which isn’t typical

Re: Does that use a lot of energy?

#166

Post by AngryData »

erelong wrote: post #109

not sure I understand the petrol car using 3x as much energy as an EV... wouldn't it make sense to convert gasoline to electricity then? I presume that must not be as efficient as other ways to convert fuel to gasoline? (I understand the math is there but... I'm temporarily failing to get it) I think lists like these might be useful for energy audits and thinking about ways to make better use of energy

If everyone had their own turbine to generate electricity from gasoline then it would be. But from a central power plant there are transmission losses which cuts out a lot of the potential efficiency increase. The obvious upfront and maintenance cost of everybody owning a personal turbine though makes that method kind of iffy.

Re: Does that use a lot of energy?

#167

Post by ropable »

jwilliams wrote: post #28

It was genuinely a surprise to see how much relative energy petrol cars use (and shame on me - I'm an electrical engineer). I mean I think I knew it intuitively, but this simple chart blew my mind.

It gets across just how ridiculously energy-dense liquid petroleum fuels are.

Re: Does that use a lot of energy?

#168

Post by noosphr »

alexfoo wrote: post #139
noosphr wrote: post #103

Earlier quoted context omitted.

Most of those technologies also need uninterrupted power supplies. Something wind, solar and batteries for the next 50 years aren't.

Pumped hydro is one solution. You bank the excess wind/solar using gravitational potential energy and then draw on that whenever you need to. https://en.wikipedia.org/wiki/Dinorwig_Power_Station

Yes, we just need to build the mountains first.

Re: Does that use a lot of energy?

#169

Post by charlie90 »

Its always interesting how complex electronics uses little energy. But its the simple stuff like heating water or turning a motors that use magnitudes more.

Physically, it makes sense, but its sort of counter intuitive in terms of utility. You might imagine the tools with the most utility use the most energy.I think thats how many people think of it.

Re: Does that use a lot of energy?

#170

Post by frankus »

OldSchool wrote: post #148
frankus wrote: post #122

Earlier quoted context omitted.

Every single ICE car driving down the highway is throwing away enough waste heat to heat a small apartment building on a freezing cold day.

IF the joules of energy in your EV battery came from gas-fired or coal-powered generation, a similar amount (~60%) was simply dumped somewhere else.

I wish we did more e.g. district heating with that waste heat in the US.
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