Tesla Model 3 revealed

[kambites]

walm said:

You do realise that most governments still SUBSIDISE solar?

They subsidise nuclear too but people don't tend to complain about that.

Fossil fuels are significantly cheaper than everything else but fossil fuels are no longer viewed as an acceptable way of generating electricity so the question becomes which of the "everything else" is most viable. I think the answer is "it depends on the situation"; a mixture of different sources seems to be the way most countries are going.

[k-ink]

Solar is not great on a small scale dotted around here and there in places like the UK. It would make more sense to put large arrays in very hot locations.

The money and effort spent on drilling for oil, building nuclear power stations, making wind turbines, hydro stations, coal power stations etc all adds up to an immense total effort. That time could simply be focused on laying out panels instead. If we can send robots to Mars I'm sure we could get some labourers to plug panels together on the floor.

Although I understand some love to see problems rather than solutions.

[rovermorris999]

Without cost-effective storage and virtually loss-free transmission solar from desert areas is a non-starter on a scale large enough to make a difference.
I don't mind subsidising nuclear because it gives 24/7/365 power on a huge scale. 'Renewables' sadly don't. I have nothing against wind, solar, tidal, whatever per se just as long as they give meaningful amounts of reliable power at competitive prices. People seem to forget that renewables are subsidised up to the eyeballs and fossil fuels are taxed likewise when comparing costs.

[walm]

k-ink said:

Solar is not great on a small scale dotted around here and there in places like the UK. It would make more sense to put large arrays in very hot locations.

The money and effort spent on drilling for oil, building nuclear power stations, making wind turbines, hydro stations, coal power stations etc all adds up to an immense total effort. That time could simply be focused on laying out panels instead. If we can send robots to Mars I'm sure we could get some labourers to plug panels together on the floor.

Although I understand some love to see problems rather than solutions.

Which bit of "more expensive" are you struggling with?

Although I understand some love to see "costs more" and think they know better.

As for subsidising nuclear - that's true in the UK for the NEW plants, but not sure about the old ones. I think they were set up under a "no public subsidies" regime, I may be wrong about that though.

[walm]

rovermorris999 said:

Without cost-effective storage and virtually loss-free transmission solar from desert areas is a non-starter on a scale large enough to make a difference.

Rubbish. Just get some Polish labourers to drop a big cable from the Sahara to Staines, how hard can it be?
Or we just send super-tankers full of car batteries and charge them up to transport home.
Some people just see problems, honestly.

[rovermorris999]

walm said:

Rubbish. Just get some Polish labourers to drop a big cable from the Sahara to Staines, how hard can it be?
Or we just send super-tankers full of car batteries and charge them up to transport home.
Some people just see problems, honestly.

You've solved it! Ring the government and let them know the good news Just don't mention basic physics.

[Tuna]

k-ink said:

It's been said before, but here goes again. Apparently if we can capture 0.1% of the Suns rays which lands on Earth we could power everything civilisation demands for free. The sensible solution would be to put vast solar arrays in hot inhabitable areas: Australian outback, Middle East, Africa, etc. This would require international cooperation of course.

We could ditch all the other power sources. But then the rich and powerful would see a loss of profits. So this obvious solution is unlikely to happen until the day after all fossil fuels are burnt.

By vast, you do mean vast - 0.1% of the earth's surface is half a million square kilometers - or twice the area of the UK. At typical panel efficiencies, we would need to cover a quarter of the Sahara desert, without any gaps. Can you imagine the civil engineering needed to do that?

Then there is the small problem of getting that power to where it's needed. We still don't have a solution for storing enough of it to usefully provide energy during the hours of darkness.

Edited by Tuna on Monday 25th April 11:48

[feef]

rovermorris999 said:

Without cost-effective storage and virtually loss-free transmission solar from desert areas is a non-starter on a scale large enough to make a difference..

What are the losses associated with power transmission? I was under the impression it was about 1% per hundred miles for high-voltage, overhead cables

That would mean a 20% loss from the Sahara to the UK, but that still means 80% of the generated power is getting here, and if that 80% can supplant a bit chunk of fossil fuel power generation then is there a barrier other than cost?

[otolith]

k-ink said:

It's been said before, but here goes again. Apparently if we can capture 0.1% of the Suns rays which lands on Earth we could power everything civilisation demands for free. The sensible solution would be to put vast solar arrays in hot inhabitable areas: Australian outback, Middle East, Africa, etc. This would require international cooperation of course.

We could ditch all the other power sources. But then the rich and powerful would see a loss of profits. So this obvious solution is unlikely to happen until the day after all fossil fuels are burnt.

Hmm. But even if we had 100% efficient solar panels, that would require an area the size of Spain. And it would need multiple areas that size, to have power 24 hours a day.

[Tuna]

otolith said:

Hmm. But even if we had 100% efficient solar panels, that would require an area the size of Spain. And it would need multiple areas that size, to have power 24 hours a day.

I *think* you mean a hundred times the area of Spain.

[k-ink]

No you are right. All we can do is burn dinosaur juice. As you were

[feef]

otolith said:

k-ink said:

It's been said before, but here goes again. Apparently if we can capture 0.1% of the Suns rays which lands on Earth we could power everything civilisation demands for free. The sensible solution would be to put vast solar arrays in hot inhabitable areas: Australian outback, Middle East, Africa, etc. This would require international cooperation of course.

We could ditch all the other power sources. But then the rich and powerful would see a loss of profits. So this obvious solution is unlikely to happen until the day after all fossil fuels are burnt.

Hmm. But even if we had 100% efficient solar panels, that would require an area the size of Spain. And it would need multiple areas that size, to have power 24 hours a day.

I'd be interested to see a comparison of efficiency between solar panels and solar-furnace power generation.

Some of the more recent developments in solar furnace technology uses the heat to melt salts which then are used to vapourise the water and turn the turbines. The stored heat in the molten salt means it can run overnight while the sun isn't shining

Some of the solar furnace plants in the states are generating Gw of power.

[Tuna]

k-ink said:

No you are right. All we can do is burn dinosaur juice. As you were

You asked why we can't do solar on a global scale. There's your answer. Currently nuclear is looking like our best option, and some of the technical advances in that area are quite promising. It's quite possible that within my children's lifetime we could move to an energy source that is zero carbon and effectively 'infinite'. The effects of that on our civilization would be far, far beyond the effect of swapping to a different car engine.

[k-ink]

Yep, definitely impossible.

[otolith]

Tuna said:

otolith said:

Hmm. But even if we had 100% efficient solar panels, that would require an area the size of Spain. And it would need multiple areas that size, to have power 24 hours a day.

I *think* you mean a hundred times the area of Spain.

I used 0.1 * area of planet / 100, though should probably have used half that, as only half the planet faces the sun at any time. So area of the UK. It's a gross simplification anyway, because solar radiance is not even, but it puts the scale of the problem into context.

[skyrover]

Takes up similar land area to the amount if houses it could supply

[k-ink]

skyrover said:

Takes up similar land area than the amount if houses it could supply

There are no houses in the middle of deserts. Or the ocean. HTH.

[Tuna]

otolith said:

I used 0.1 * area of planet / 100, though should probably have used half that, as only half the planet faces the sun at any time. So area of the UK. It's a gross simplification anyway, because solar radiance is not even, but it puts the scale of the problem into context.

Doh! Yes of course

[rovermorris999]

It's a shame basic physics isn't taught to everyone. This thread has turned into a waste of pixels. Time to go.

[Tuna]

k-ink said:

Yep, definitely impossible.

That last image is First Solar, which cost $2.5 billion to cover 9 square miles. You want to cover 20,000 times that area.. which would cost 50 Trillion dollars if you ignore the complication of building at that scale.

Of course we're not saying solar is impossible. It has a useful place in a mixed source strategy. However, it's not a magic pill and there are huge technical and financial challenges to overcome to use it on a large scale.