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How cheap does solar power need to get before it takes over the world?

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Re: How cheap does solar power need to get before it takes over the world?

#81

Post by pjc50 »

swombat wrote: post #60
Gustomaximus wrote: post #48

Earlier quoted context omitted.

Similar to pumped water storage I wonder if we could do a household version with weight. Something like the gravity light (gravitylight.org) but on larger scale. I wonder if we could see a resurgence of chimneys on houses except now instead of letting smoke out they contain a XY ton weights that gets pushed up by excess solar capacity during the day, and then drops by evening powering the house. I have no idea if tha…

A much better and denser option for storing energy mechanically is flywheels. I haven't researched what happened to this option since but when I was looking into it 15 years ago it seemed like a good option that needed more R&D into frictionless axles and vacuum chambers.

The Formula 1 "KERS" system is based around high-speed flywheels and seems to work quite well.

Re: How cheap does solar power need to get before it takes over the world?

#82

Post by almostarockstar »

CapitalistCartr wrote: post #18
oolongCat wrote: post #13

Earlier quoted context omitted.

If the whole world could get their s * together, we can perhaps have a worldwide grid.

Electricity transmission is constrained by line loss, which is proportionate to amperage. To minimize it, voltage is raised to as much as over a million volts, keeping amperage down. This makes for very serious cross-country transmission lines, and electric companies still lose a quarter of the generated power to it. In my opinion, the two great strengths of solar are cleaner power and localizing power generating wit…

Unless you user superconductors, like cooled aluminium (if I remember correctly). There is a lot of research in this area at the moment. If you cool a conductor low enough, the resistance reduces dramatically and you can transmit electricity with very little line loss.

Re: How cheap does solar power need to get before it takes over the world?

#83

Post by xbmcuser »

WaylonKenning wrote: post #27
martinald wrote: post #11

I think the issue is that OK, say we managed to get to 100% electricity being solar when the sun is shining. You'd still have the time the sun is not shining, which would likely be more expensive than before (a gas powered plant would only be running half the time - effectively doubling its capital/construction cost per kWh). So you'd definitely have an improvement on some levels but I'm not sure that would really he…

Everyone seems a bit obsessed by batteries as a storage method, when we have more traditional methods: - Pumped-storage hydroelectricity - https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... . Sure it's not suitable everywhere. - There's always Molten Salt as well - http://www.solarreserve.com/en/technology/molten-salt-energy... . Also, solar isn't the be all and end all of renewable energy generation. Wi…

Batteries are the best bet for going off grid not for utilities based solar. Now that in more cities and states of US the utilities are getting net metering banned for home solar.

Re: How cheap does solar power need to get before it takes over the world?

#84

Post by dagw »

almostarockstar wrote: post #82
CapitalistCartr wrote: post #18

Earlier quoted context omitted.

Electricity transmission is constrained by line loss, which is proportionate to amperage. To minimize it, voltage is raised to as much as over a million volts, keeping amperage down. This makes for very serious cross-country transmission lines, and electric companies still lose a quarter of the generated power to it. In my opinion, the two great strengths of solar are cleaner power and localizing power generating wit…

Unless you user superconductors, like cooled aluminium (if I remember correctly). There is a lot of research in this area at the moment. If you cool a conductor low enough, the resistance reduces dramatically and you can transmit electricity with very little line loss.

The problem is that it costs lots of energy to cool things so it's difficult to end up ahead unless we make dramatic advances in high temperature superconductors.

Re: How cheap does solar power need to get before it takes over the world?

#85

Post by kaybe »

olau wrote: post #78
WaylonKenning wrote: post #27

Earlier quoted context omitted.

Everyone seems a bit obsessed by batteries as a storage method, when we have more traditional methods: - Pumped-storage hydroelectricity - https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... . Sure it's not suitable everywhere. - There's always Molten Salt as well - http://www.solarreserve.com/en/technology/molten-salt-energy... . Also, solar isn't the be all and end all of renewable energy generation. Wi…

Wind pioneer and former CTO of Siemens Wind Power is currently working on energy storage using rocks instead of a molten salt - he's blogging about it in the Danish engineering news site ing.dk. Molten salt is efficient because of the phase change, but also much more difficult and expensive to handle than a big (well enormous) bunch of hot rocks. Last thing I heard, he's currently trying to get demonstration plant up…

We had research show that you can offset storage with capacity to some degree. [0]

Some numbers: 100% renewable energy with a capacity of 340% would require 8% storage just for Germany, 3.8% for Europe (due to larger area which means more diverse weather). Also 8% for Europe using no solar and more wind instead.

The 340% capacity is needed to get to the 100% coverage since there is more downtime compared to old energy which had 180% in 2007.

If we go to 390% capacity (which corresponds to 170 GW additional production as calculated for Germany) we only need 0.9% storage.

Depending on the relative pricing of additional capacity and storage, the price for building the whole infrastructure can go down by half. (The upper limit given in numbers is of the same order of magnitude as Europe's GDP in 2009, 12·10^12 €)

[0] (German) http://onlinelibrary.wiley.com/doi/10.1002/piuz.201201301/ab...

Re: How cheap does solar power need to get before it takes over the world?

#86

Post by Osiris30 »

martinald wrote: post #11

I think the issue is that OK, say we managed to get to 100% electricity being solar when the sun is shining. You'd still have the time the sun is not shining, which would likely be more expensive than before (a gas powered plant would only be running half the time - effectively doubling its capital/construction cost per kWh). So you'd definitely have an improvement on some levels but I'm not sure that would really he…

Every time Solar and Wind and other renewables get mentioned - people get very confused over what is 'baseload', 'intermittency', why those terms are important and the whole "oh but the sun doesn't always shine and the wind doesn't always blow argument.

See my comment further below https://news.ycombinator.com/item?id=11520789

Re: How cheap does solar power need to get before it takes over the world?

#87

Post by ars »

imaginenore wrote: post #76
marvin wrote: post #64

Earlier quoted context omitted.

Did you compensate for cost in this example?

Cost has nothing to do with this argument. He is talking about energy density.

Quite the opposite. For grid storage (in contrast to cars) energy density is irreverent (there is plenty of space). What matters is cost.

Re: How cheap does solar power need to get before it takes over the world?

#88

Post by thinkcontext »

Gustomaximus wrote: post #48
WaylonKenning wrote: post #27

Earlier quoted context omitted.

Everyone seems a bit obsessed by batteries as a storage method, when we have more traditional methods: - Pumped-storage hydroelectricity - https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... . Sure it's not suitable everywhere. - There's always Molten Salt as well - http://www.solarreserve.com/en/technology/molten-salt-energy... . Also, solar isn't the be all and end all of renewable energy generation. Wi…

Similar to pumped water storage I wonder if we could do a household version with weight. Something like the gravity light (gravitylight.org) but on larger scale. I wonder if we could see a resurgence of chimneys on houses except now instead of letting smoke out they contain a XY ton weights that gets pushed up by excess solar capacity during the day, and then drops by evening powering the house. I have no idea if tha…

You are referring to a hydraulic accumulator[0], such systems were built in the 19th century, though not for household use.

There is a modern effort to use the technology in a massively scaled up fashion by Heindl Energy[1]. Their concept uses pumped water to raise a rock weight 100 meters or more in diameter.

[0] https://en.wikipedia.org/wiki/Hydraulic_accumulator [1] http://www.heindl-energy.com/hydraulic-rock-storage/overview...

Re: How cheap does solar power need to get before it takes over the world?

#89

Post by RNiK »

Right now there are 2 different articles on Hacker News front page stating the opposite (almost).

Bloomberg article (http://www.bloomberg.com/news/articles/2016-04-14/first-sola...) states the following: "First Solar is producing panels for as little as 40 cents a watt, or about 15 percent less than China’s Trina Solar Ltd. In 2019, First Solar’s module cost could be as low as 25 cents a watt, according to analysts’ models.".

VOX article (http://www.vox.com/2016/4/18/11415510/solar-power-costs-inno...) states the following: "How cheap? Sivaram and Kann argue that the industry should set a goal of pushing the installed price of solar to 25 cents per watt by 2050 — down from around $3 per watt today."

Re: How cheap does solar power need to get before it takes over the world?

#90

Post by jasonwatkinspdx »

dredmorbius wrote: post #34
WaylonKenning wrote: post #27

Earlier quoted context omitted.

Everyone seems a bit obsessed by batteries as a storage method, when we have more traditional methods: - Pumped-storage hydroelectricity - https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... . Sure it's not suitable everywhere. - There's always Molten Salt as well - http://www.solarreserve.com/en/technology/molten-salt-energy... . Also, solar isn't the be all and end all of renewable energy generation. Wi…

No idea why the hivemind is downvoting you, but you're absolutely correct. A couple of additions and caveats. Friend of mine at ORNL has been talking up compressed air energy storage (CAES). I'm somewhat dubious due to the Boyles law heating/cooling problem (gasses heat when compressed, cool when expanded, and the resulting heat flows affect both efficiency and equipment function -- gas turbines don't spin well when…

> Carbon source from seawater appears somewhat promising, though my concern is that there's been 50 years of research without a large-scale demonstration project, making me suspect deeper issues.

I haven't seen anything about it recently, but the Navy was/is funding a demonstration plant in Hawaii. I really hope it works out as I'm skeptical that the developing world will shift to electric vehicles anytime soon.

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