8 ms·

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,

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 help that much. The real big breakthrough would be somme big improvement on storage. I'm not convinced this will happen quickly (at least not in anyway similar to the declining cost of PV panels). The consumer electronics industry has been paying $$$ for decades for better batteries/battery r&d and has seen pretty poor gains. I think Tesla and the electric car manufacturers will definitely rapidly get the price down by say 30% because of economies of scale but will then hit a brick wall as more of the cost becomes raw materials, transport, etc which will set a floor on the cost of batteries. Happy to be proved wrong though :)

oolongCat 11y ago
If the whole world could get their s* together, we can perhaps have a worldwide grid.
- CapitalistCartr 11y ago
  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 with its use.
  - marshray 11y ago
    Proportional to the square of current (amperage). Or alternatively, inversely proportional to the square of voltage.
  - almostarockstar 11y ago
    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.
    - dagw 11y ago
      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.
eru 11y ago
> The real big breakthrough would be somme big improvement on storage. I'm not convinced this will happen quickly (at least not in anyway similar to the declining cost of PV panels). The consumer electronics industry has been paying $$$ for decades for better batteries/battery r&d and has seen pretty poor gains. Actually, it's not too bad, just slower. Batteries improve around 8% per year, if I remember right. That's less than semiconductor based stuff improved when Moore's law held, but pretty impressive compared to lots of other technologies.
- p1mrx 11y ago
  Li-ion 18650 cells held 2300mAh in 2005[1], and 3350mAh today[2]. That's an increase of 45% in just under 11 years. If capacity were really growing at 8% per year, then 18650 cells should have a capacity of 5300mAh by now. [1] http://www.candlepowerforums.com/vb/showthread.php?88468-Triton-data-on-LiIon-cells-updated&p=1044873&viewfull=1#post1044873 http://www.candlepowerforums.com/vb/showthread.php?88468-Tri... [2] http://www.candlepowerforums.com/vb/showthread.php?417736-Test-Review-of-Sanyo-Panasonic-NCR18650GA-3500mAh-(Red)&p=4875552&viewfull=1#post4875552 http://www.candlepowerforums.com/vb/showthread.php?417736-Te...
  - marvin 11y ago
    Did you compensate for cost in this example?
    - imaginenore 11y ago
      Cost has nothing to do with this argument. He is talking about energy density.
      - ars 11y ago
        Quite the opposite. For grid storage (in contrast to cars) energy density is irreverent (there is plenty of space). What matters is cost.
      - eru 11y ago
icefox 11y ago
Of course if the more solar we get combined with cheap computing a market will emerge where there are two prices of electricity. Car charging will probably be first where they turn on/off depending on the solar output. Refrigerators and AC could follow.
- laurencerowe 11y ago
  In the UK we have Economy 7 which offers lower rates at night. https://en.wikipedia.org/wiki/Economy_7 https://en.wikipedia.org/wiki/Economy_7. It's generally used in homes with 'storage heaters' which heat up overnight and release heat during the day while you're out at work. https://en.wikipedia.org/wiki/Storage_heater https://en.wikipedia.org/wiki/Storage_heater
  - Qantourisc 11y ago
    I think we are more talking about hourly prices. You should take a look at the electric market, prices fluctuate heavy. So heavy even in some countries, that you are PAYING when you put electricity on the net: http://www.elia.be/nl/grid-data/balancing/onevenwichtsprijs http://www.elia.be/nl/grid-data/balancing/onevenwichtsprijs
- spacecowboy_lon 11y ago
  Bit of a problem if you have to do that "turn of electric car charging" if you have a non trivial number of electric cars.
- ZeroGravitas 11y ago
  You can already charge your EV for less if you let the utility modulate the charge rate to match their demand/supply. http://www.emotorwerks.com/index.php/component/rsform/form/14-ssp-signup http://www.emotorwerks.com/index.php/component/rsform/form/1... In areas where the utility is not set up to do this, you can programming it to monitor the grid and prefer charging when the grid is less carbon intensive.
WaylonKenning 11y ago
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_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-storage http://www.solarreserve.com/en/technology/molten-salt-energy.... Also, solar isn't the be all and end all of renewable energy generation. Wind, Solar, Hydro, and Geothermal all have different strengths and weaknesses, and flexibility of generation is important. But above all, I think security of supply is probably the number 1 requirement (unless you're a big fan of load shedding - https://en.wikipedia.org/wiki/Rolling_blackout https://en.wikipedia.org/wiki/Rolling_blackout), and therefore, we'll still need energy sources that are reliable. I predict a move away from coal towards natural gas. Sure it's not perfect, but it's not the worst either.
- dredmorbius 11y ago
  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 iced solid). Pumped-hydro is the most efficient storage solution bar none, but is painfully restricted by siting opportunities. Being able to use oceans as a lower baisin might address this, though salt-water engineering is a significant concern (corrosion and other issues). Interesting to see molten salt as at large scale that pencils out a viable for even, say, a two week total energy replacement solution for the US. You'd need tankage (insulated) roughly corresponding to current Oaklahoma oil transshipment storage facilities. Electricity-to-fuel is another option, with Sabatier and Fischer-Tropsch cycles both proven. 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 actually am a fan of load-shedding, and suspect that the concept of dispatchable load as opposed to supply may be part of the future way of thinking. Coal => gas is a no-brainer, though also not a total solution, by a long shot. Geothermal is highly underrated, especially if currently protected areas are opened for consideration. The Yellowstone caldera could possibly supply up to 15% of total US electrical demand.
graycat 11y ago
Short summary: The issue is not the cost of solar but the cost of storage.
- Qwertious 11y ago
  Currently, peak electricity costs are in the daytime. This makes no sense if storage is the biggest problem of the present.
  - graycat 11y ago
    We're talking about the grid, and there's plenty of demand when solar is not available -- nights, rain, snow, clouds, long winter nights, etc. To be brief, I left it out, but my ballpark guesstimate is that, due to the cost of storage, for the main grid, solar for free is still not cheap enough. So, that is an answer to a question in the OP -- how cheap does solar have to be? My guesstimate is $0.00 per megawatt hour is still not cheap enough. In really simple terms, the grid doesn't want solar, even for free because of the need for storage and the fact that solar is unstable, e.g., due to just a sudden summer thunderstorm. The grid is super big on stability -- a small source of instability, and the whole grid of the US NE can go down, and at least once did. Another, related point is that often the wholesale cost of power on the grid has been ballpark $0.005 per KWh, that is, half a penny per kilowatt hour. So, already, now, on the grid, intermittent power is nearly worthless, even when it is excess power from a rock solidly stable source. And why might there be excess power? Because at the generators it's not so easy to adjust power levels quickly. So, when there's an excess, just sell it off where can, get half a cent for it, and go on. Very much what the grid wants from the generators is rock solidly stable power, 24 x 7, no snap, crackle or pop, not even for two seconds, for years at a time. And we have that, now, that is, at least from the generators. Sure, for the lines and poles out to the burbs, during an ice storm, the reliability can be lower. Solar? Fine, if it is cheap enough AND there is good storage to make it reliable enough AND the storage is not too expensive. Again, the short answer, for solar, for the grid -- the storage costs too much. Again, we're talking about the grid. There are other candidate uses for solar power -- taking salt out of water (get to store the clean water), pumping water uphill (if have a big dam handy), getting hydrogen from water (get to store the hydrogen or just pump it into a pipeline), making gasoline from coal and water (get to store the gasoline and pump it into a pipeline). So, these uses all have the feature that there is a good way to store the results of the solar power. People have worked hard on storage for a long time, and that there is little or none installed on the grid indicates that so far no one has a good approach to storage. Likely, get the solar panels with 100% efficiency for free, and the issue will remain -- cost of storage. A lot of this is just my opinion, but what's been deployed on the real grid makes me suspect I'm basically correct. We can be sure that lots of smart engineers have checked the figures very carefully, and so have the public utility commissions, so we don't really have to go over all the figures ourselves. It's pretty clear that the smart engineers that have done all the arithmetic carefully don't want solar for the grid. But, sure, some people want to tax carbon, and tax it enough that solar with available storage will be cheap enough. That's another issue.
Osiris30 11y ago
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 https://news.ycombinator.com/item?id=11520789
ZeroGravitas 11y ago
Lots of gas plants already run only a fraction of the time. This is because demand goes up and down on both a short and long term basis e.g. in many places the peak daily demand is just after lunchtime, and peak yearly demand is mid-summer, with an absolute peak at noon on one summer day. Without grid scale storage demand must be matched, hence ridiculously expensive gas peaker plants and transmission lines built for these peak loads. It is in fact these very expensive gas plants that solar is destroying the market for first, both because they are the most expensive to run, but also because solar happens to align with the natural peaks in demand.

oolongCat 11y ago

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

CapitalistCartr 11y ago
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 with its use.
- marshray 11y ago
  Proportional to the square of current (amperage). Or alternatively, inversely proportional to the square of voltage.
- almostarockstar 11y ago
  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.
  - dagw 11y ago
    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.

eru 11y ago

> The real big breakthrough would be somme big improvement on storage. I'm not convinced this will happen quickly (at least not in anyway similar to the declining cost of PV panels). The consumer electronics industry has been paying $$$ for decades for better batteries/battery r&d and has seen pretty poor gains. Actually, it's not too bad, just slower. Batteries improve around 8% per year, if I remember right. That's less than semiconductor based stuff improved when Moore's law held, but pretty impressive compared to lots of other technologies.

p1mrx 11y ago
Li-ion 18650 cells held 2300mAh in 2005[1], and 3350mAh today[2]. That's an increase of 45% in just under 11 years. If capacity were really growing at 8% per year, then 18650 cells should have a capacity of 5300mAh by now. [1] http://www.candlepowerforums.com/vb/showthread.php?88468-Triton-data-on-LiIon-cells-updated&p=1044873&viewfull=1#post1044873 http://www.candlepowerforums.com/vb/showthread.php?88468-Tri... [2] http://www.candlepowerforums.com/vb/showthread.php?417736-Test-Review-of-Sanyo-Panasonic-NCR18650GA-3500mAh-(Red)&p=4875552&viewfull=1#post4875552 http://www.candlepowerforums.com/vb/showthread.php?417736-Te...
- marvin 11y ago
  Did you compensate for cost in this example?
  - imaginenore 11y ago
    Cost has nothing to do with this argument. He is talking about energy density.
    - ars 11y ago
      Quite the opposite. For grid storage (in contrast to cars) energy density is irreverent (there is plenty of space). What matters is cost.
    - eru 11y ago

icefox 11y ago

Of course if the more solar we get combined with cheap computing a market will emerge where there are two prices of electricity. Car charging will probably be first where they turn on/off depending on the solar output. Refrigerators and AC could follow.

laurencerowe 11y ago
In the UK we have Economy 7 which offers lower rates at night. https://en.wikipedia.org/wiki/Economy_7 https://en.wikipedia.org/wiki/Economy_7. It's generally used in homes with 'storage heaters' which heat up overnight and release heat during the day while you're out at work. https://en.wikipedia.org/wiki/Storage_heater https://en.wikipedia.org/wiki/Storage_heater
- Qantourisc 11y ago
  I think we are more talking about hourly prices. You should take a look at the electric market, prices fluctuate heavy. So heavy even in some countries, that you are PAYING when you put electricity on the net: http://www.elia.be/nl/grid-data/balancing/onevenwichtsprijs http://www.elia.be/nl/grid-data/balancing/onevenwichtsprijs
spacecowboy_lon 11y ago
Bit of a problem if you have to do that "turn of electric car charging" if you have a non trivial number of electric cars.
ZeroGravitas 11y ago
You can already charge your EV for less if you let the utility modulate the charge rate to match their demand/supply. http://www.emotorwerks.com/index.php/component/rsform/form/14-ssp-signup http://www.emotorwerks.com/index.php/component/rsform/form/1... In areas where the utility is not set up to do this, you can programming it to monitor the grid and prefer charging when the grid is less carbon intensive.

WaylonKenning 11y ago

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_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-storage http://www.solarreserve.com/en/technology/molten-salt-energy.... Also, solar isn't the be all and end all of renewable energy generation. Wind, Solar, Hydro, and Geothermal all have different strengths and weaknesses, and flexibility of generation is important. But above all, I think security of supply is probably the number 1 requirement (unless you're a big fan of load shedding - https://en.wikipedia.org/wiki/Rolling_blackout https://en.wikipedia.org/wiki/Rolling_blackout), and therefore, we'll still need energy sources that are reliable. I predict a move away from coal towards natural gas. Sure it's not perfect, but it's not the worst either.

dredmorbius 11y ago
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 iced solid). Pumped-hydro is the most efficient storage solution bar none, but is painfully restricted by siting opportunities. Being able to use oceans as a lower baisin might address this, though salt-water engineering is a significant concern (corrosion and other issues). Interesting to see molten salt as at large scale that pencils out a viable for even, say, a two week total energy replacement solution for the US. You'd need tankage (insulated) roughly corresponding to current Oaklahoma oil transshipment storage facilities. Electricity-to-fuel is another option, with Sabatier and Fischer-Tropsch cycles both proven. 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 actually am a fan of load-shedding, and suspect that the concept of dispatchable load as opposed to supply may be part of the future way of thinking. Coal => gas is a no-brainer, though also not a total solution, by a long shot. Geothermal is highly underrated, especially if currently protected areas are opened for consideration. The Yellowstone caldera could possibly supply up to 15% of total US electrical demand.

graycat 11y ago

Short summary: The issue is not the cost of solar but the cost of storage.

Qwertious 11y ago
Currently, peak electricity costs are in the daytime. This makes no sense if storage is the biggest problem of the present.
- graycat 11y ago
  We're talking about the grid, and there's plenty of demand when solar is not available -- nights, rain, snow, clouds, long winter nights, etc. To be brief, I left it out, but my ballpark guesstimate is that, due to the cost of storage, for the main grid, solar for free is still not cheap enough. So, that is an answer to a question in the OP -- how cheap does solar have to be? My guesstimate is $0.00 per megawatt hour is still not cheap enough. In really simple terms, the grid doesn't want solar, even for free because of the need for storage and the fact that solar is unstable, e.g., due to just a sudden summer thunderstorm. The grid is super big on stability -- a small source of instability, and the whole grid of the US NE can go down, and at least once did. Another, related point is that often the wholesale cost of power on the grid has been ballpark $0.005 per KWh, that is, half a penny per kilowatt hour. So, already, now, on the grid, intermittent power is nearly worthless, even when it is excess power from a rock solidly stable source. And why might there be excess power? Because at the generators it's not so easy to adjust power levels quickly. So, when there's an excess, just sell it off where can, get half a cent for it, and go on. Very much what the grid wants from the generators is rock solidly stable power, 24 x 7, no snap, crackle or pop, not even for two seconds, for years at a time. And we have that, now, that is, at least from the generators. Sure, for the lines and poles out to the burbs, during an ice storm, the reliability can be lower. Solar? Fine, if it is cheap enough AND there is good storage to make it reliable enough AND the storage is not too expensive. Again, the short answer, for solar, for the grid -- the storage costs too much. Again, we're talking about the grid. There are other candidate uses for solar power -- taking salt out of water (get to store the clean water), pumping water uphill (if have a big dam handy), getting hydrogen from water (get to store the hydrogen or just pump it into a pipeline), making gasoline from coal and water (get to store the gasoline and pump it into a pipeline). So, these uses all have the feature that there is a good way to store the results of the solar power. People have worked hard on storage for a long time, and that there is little or none installed on the grid indicates that so far no one has a good approach to storage. Likely, get the solar panels with 100% efficiency for free, and the issue will remain -- cost of storage. A lot of this is just my opinion, but what's been deployed on the real grid makes me suspect I'm basically correct. We can be sure that lots of smart engineers have checked the figures very carefully, and so have the public utility commissions, so we don't really have to go over all the figures ourselves. It's pretty clear that the smart engineers that have done all the arithmetic carefully don't want solar for the grid. But, sure, some people want to tax carbon, and tax it enough that solar with available storage will be cheap enough. That's another issue.

Osiris30 11y ago

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 https://news.ycombinator.com/item?id=11520789

ZeroGravitas 11y ago

Lots of gas plants already run only a fraction of the time. This is because demand goes up and down on both a short and long term basis e.g. in many places the peak daily demand is just after lunchtime, and peak yearly demand is mid-summer, with an absolute peak at noon on one summer day. Without grid scale storage demand must be matched, hence ridiculously expensive gas peaker plants and transmission lines built for these peak loads. It is in fact these very expensive gas plants that solar is destroying the market for first, both because they are the most expensive to run, but also because solar happens to align with the natural peaks in demand.