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Does that use a lot of energy?

hannahritchie.github.io

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Re: Does that use a lot of energy?

#201

Post by Leno1225 »

zahlman wrote: post #183
londons_explore wrote: post #181

Interestingly, the latest generation of LED lights are so efficient that it makes little financial sense to bother having a light switch. 330 lumens per watt from recent Phillips bulbs! The cost of having an electrician wire that switch is probably more than a little 2.5 watt light will use in it's lifespan - particularly when you account for the fact lights in hallways are probably in use most of the time anyway. Ad…

What if you want to turn it off to have darkness?

Classic example of “we figured out we could, didn’t consider if we should”

Re: Does that use a lot of energy?

#202

Post by fritzo »

How does it make sense to compare renewable vs non-renewable energy sources?

Where does that electric car's energy come from?

Suppose the electric car's energy is solar. Then driving the electric car consumes zero barrels of oil, and so is infinitely more renewable than the petrol car. Or how efficient is the electric car at capturing available energy? Maybe the petrol car is 20% efficient at capturing available oil reserve energy. But the electric car is like 1e-30% efficient at capturing available solar output. Incomparable.

Re: Does that use a lot of energy?

#203

Post by supertrope »

Leno1225 wrote: post #200
noosphr wrote: post #168

Earlier quoted context omitted.

Yes, we just need to build the mountains first.

Yeah, or water towers. No need to play god here.

Pumped hydro energy storage relies on the cheapness of water and existing geology. If you have to build the chambers instead of damming a river it's too expensive. Most of the good spots to have a reservoir are already used. If you have to manufacture the bulk media instead of just using water it's too expensive.

Re: Does that use a lot of energy?

#204

Post by supertrope »

anjel wrote: post #131

This needs a phantom power feature. How much does your phone charger consume when its it charging your phone but still pligged in. Whats the cost of your TV when its "off?"

Switching mode power supplies use milliwatts when there's no load. Appliances are usually 3W or less when off as they need to keep the IR sensor turned off. The best appliances are <1W.

Re: Does that use a lot of energy?

#205

Post by quickthrowman »

megaman821 wrote: post #173
quickthrowman wrote: post #116

Earlier quoted context omitted.

Gasoline engines are around 30-35% efficient, the rest is lost as heat. That goes for whether they’re spinning an alternator as part of an engine-generator set or just moving a vehicle. You can’t get more than 35-40% efficiency so converting to electricity is a wash, you lose the energy to heat no matter what. Also, the chart does not take into account how the electricity for the EV is generated, it would be just as…

To get those types of numbers you would have to be charging from a grid that is nearly 100% coal. Real grids heavily favor EVs.

Yeah I probably should’ve mentioned that the more solar/wind/hydro you use to charge an EV, the more the efficiency goes up, thanks.

Re: Does that use a lot of energy?

#206

Post by nomel »

Leno1225 wrote: post #200
noosphr wrote: post #168

Earlier quoted context omitted.

Yes, we just need to build the mountains first.

Yeah, or water towers. No need to play god here.

There are exactly zero economically viable pumped water storage systems where water towers are involved. If you do the math for the amount of a mass of water, you'll see why! It's not feasible.

Re: Does that use a lot of energy?

#207

Post by cogman10 »

lesuorac wrote: post #198
eru wrote: post #149

Earlier quoted context omitted.

I love Technology Connections, but he has no idea what discounting is in economics. Or at least he writes his videos as if he doesn't.

What discount rate are you using? Solar has one of the lowest capital costs [1] so the discounting works in it's favor. And then the non-discountable operating costs also works in its favor since the fuel supply (light) is free. [1]: https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#...

Yup. It's why even in fairly red states like my own (Idaho) solar, wind, and battery are going up everywhere. Even without significant subsidies the economics are really good for renewables.

They'd be even better if we didn't have extreme tariffs on China.

That's actually what's convinced me that renewables are a better choice than nuclear. I still like nuclear, but renewables are just so much easier and faster to deploy while being a lot cheaper. To make nuclear competitive requires regulatory changes along with a government that's simply willing to tell it's NIMBY citizens YIMBY.

Government literally has to get in the way of renewable deployments at this point to stop them.

Re: Does that use a lot of energy?

#208

Post by cogman10 »

londons_explore wrote: post #181

Interestingly, the latest generation of LED lights are so efficient that it makes little financial sense to bother having a light switch. 330 lumens per watt from recent Phillips bulbs! The cost of having an electrician wire that switch is probably more than a little 2.5 watt light will use in it's lifespan - particularly when you account for the fact lights in hallways are probably in use most of the time anyway. Ad…

Do you have a link to the 300 lumens per watt lighting? I'm curious.

I think that mostly only applies bulbs without inverters.

Re: Does that use a lot of energy?

#209

Post by cogman10 »

noosphr wrote: post #127
ramidarigaz wrote: post #111

Earlier quoted context omitted.

> Whenever you do the real world calculation for what an electric cars CO2 profile looks like it turns out to be the same as a gasoline car unless your country is majority nuclear. Not at all true: https://www.carboncounter.com/ US-specific but you can even pick a state and it will use the generation mix of that state

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.

The wind blows, water flows, nuclear glows. Further, demand's at lows.

In my state (idaho) at night the power mixture is primarily renewable/clean because of this.

Re: Does that use a lot of energy?

#210

Post by alexfoo »

nomel wrote: post #206
Leno1225 wrote: post #200

Earlier quoted context omitted.

Yeah, or water towers. No need to play god here.

There are exactly zero economically viable pumped water storage systems where water towers are involved. If you do the math for the amount of a mass of water, you'll see why! It's not feasible.

Indeed, you can get a sense of the scale on the Dinorwig wikipedia page and the pages it links to.

It has a storage capacity of about 9.1GWh.

The upper reservoir (https://en.wikipedia.org/wiki/Marchlyn_Mawr) holds 9.2 million cubic meters of water.

So 1 million cubic meters of water provides ~1GWh.

We can see how that compares in terms of raw GPE (Gravitational Potential Energy):

1 million cubic meters of water = 1E6 * 1E3 kg = 1E9 kg

There's roughly a 500m vertical drop between the upper and lower takes at Dinorwig so:

1E9 kg * 500 m * 9.8 m/(s^2) = 4.9E12 J =~ 1.36GWh

As for water towers, if you look at something like the Roihuvuori tower in Helsinki (from https://en.wikipedia.org/wiki/Water_tower) which is one of the largest:

Height: 52m, Capacity: 12000 cubic meters

If we are generous and say that all of the water is stored at the maximum height then:

12000 * 1E3 kg * 52m * 9.8 m/(s^2) =~ 1.7MWh

You'd need over 5000 of them to match what Dinorwig can provide.

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