7 ms·

Repowering California for all purposes with wind, water, and sunlight [pdf]

51 points by ejr 12y ago

leccine 12y ago
You still need a base power plant and few others for controlling the amount of energy in the system. Using only renewable is kind o hard. If we can figure out a way to store energy the way we can access it very quickly with arbitrary output, we could move on to renewables exclusively.
- jerven 12y ago
  No we need to be able to shed unwanted power. Generation using renewable sources can be over provisioned, and still be economically feasible. Power usage fluctuations are thé key issue to manage. As wind is a very good base load provider. Don't look at capacity factor that is very misleading.
  - schainks 12y ago
    > As wind is a very good base load provider. What? Please show us where the wind blows 24 hours a day, 365 days a year, every year. Not being a nay-sayer, but your comment is very misleading. "Good base load provider" means high availability - reliable enough so the lights don't go out. When's the last time you remember a power outage in the US that did not make the news? Yeah, that kind of availability. Outages are rare enough that they make the news when they do happen. Right now, wind cannot provide this kind of "base load" guarantee unless we overbuild a huge amount of capacity and implement a very sophisticated real-time system to manage all the inputs/outputs, and even then you'll be lucky to generate stable baseline load. China's trying right now and having a very difficult time both delivering stable power, and making money doing it[1]. [1] http://www.windpowermonthly.com/article/1171987/analysis---chinese-wind-curtailments-double-2012 http://www.windpowermonthly.com/article/1171987/analysis---c...
    - jerven 12y ago
      What is base load? Its the minimum load required in a network or is it those plants for whom it is uneconomical to go below a certain output. For the first no power plant is truly base load as all plants must shutdown sometimes. So you need to look at a system. So taking into account that in a large area like California it always blows some where, can wind generate the minimal base load at any time. For wind the law of large numbers eventually means that given a per wind turbine capacity factor of 36% a pure wind net achieves 36% capacity factor. If the 36% is the day peak load, then at 18% you are at night low load, considering that wind can be base load. On the second base load is pump it when you got it e.g. because it costs to much to ramp down (coal, nuclear) or because you got the power anyway (wind, day/noon solar) then yes wind is base load. Single wind turbines are not base load power plants, but when you have thousands of them over a large area they start to guarantee with high accuracy a minimal load with very good prediction properties. Of course this ignores economic efficiency, but that depends very much on oil prizes. e.g. The us uses 18 million barrels of oil a day. That means the yearly oil consumption of the US is very roughly equivalent to the volume of oil required to flood Rhode island state one foot deep. Which on the face of it does not seem economically efficient but at the moment it is.
  - leccine 12y ago
    What? You have no idea what you are talking about. But anyways, thanks for the downvotes retards.
beloch 12y ago
This paper proposes converting California's power generation over to wind and solar, with electric vehicles and electrically generated hydrogen vehicles replacing all others. All use of fossil fuels and nuclear power is to be phased out. Notably, it suggests that hydroelectric power should be used to balance loads. i.e. It proposes that California's power grid be stabilized with only hydroelectric power as an on-demand source of generation. Firstly, in 2013 California imported 32.7% of it's electricity. California has little control over how this is generated. Of the power used by California, 40.8% is from Natural Gas, 8.1% is hydroelectric, 6.0% is Nuclear, 4.3% is from wind power, 4.2% is geothermal, 2.1% is from biomass, and 1.4% is solar[1]. Natural Gas and Nuclear power are both excellent on-demand sources of power, and currently meet 46.8% of California's electricity requirements. If these power sources are to be phased out, they must be replaced with energy sources that are on-demand. Wind and solar do not fit this description. Hydro does, but quintupling California's hydroelectric capacity will have a huge impact on the environment. This paper greatly underestimates how much on-demand power generation capacity a power grid needs in order to be stable. Side note: California currently derives little of it's electricity from wind or solar power. Electric vehicle batteries carry a high environmental cost to produce, so it is imperative that the energy they are charged with be of renewable origin for any net environmental benefits to be reaped. Given that 40.8% of California's electricity currently comes from natural gas, it's clear that anyone plugging their EV's into California's grid is doing the environment no favors. [1]http://energyalmanac.ca.gov/electricity/electricity_gen_1983-2013.xls http://energyalmanac.ca.gov/electricity/electricity_gen_1983...
- schainks 12y ago
  I'd like to clear up your terminology a little bit, since the way you use "on demand" actually means two different use-cases. You're referring to "spinning reserve" versus "on-demand" sources of power. "Spinning reserves" are plants that we keep online in a "ready" state, but disconnected from the grid until we need them. "Spinning reserves" are kept online in the case of a failure elsewhere on the grid, or to adapt to load changes throughout the day. These plants are cost-effective for this use case. "On-demand" facilities are plants that have very fast spin-up time, and so they can be brought "online" from a powered-off very quickly. These kinds of plants are also cost-effective to cycle between both states. Natural Gas Combustion Turbines happen to have fast startup time (fast=minutes), and are cost efficient to keep running, so they're used on the grid for both "on demand" and "spinning reserve applications", as it's cheap to cycle them between both states and cheap to keep them spinning (as long as natural gas is cheap). Even better "on demand" sources of power are batteries, since they can be flipped on/off the grid like a lightswitch, but I digress. Nuclear power plants, on the other hand, are awful for "on demand" applications since they take many days, weeks or months to fully power on/power off, and it costs a lot of money to do so. But, they are good as "spinning reserve" facilities, since they produce very cheap electricity once they are online.
timthorn 12y ago
David MacKay's "Without Hot Air" is an excellent investigation of what needs to be done to power the UK. http://www.withouthotair.com/ http://www.withouthotair.com/
schainks 12y ago
I'd like to take a moment to point out another really great "renewable" technology that is a clever arbitrage hack using power prices: Compressed Air Energy Storage. (http://en.wikipedia.org/wiki/CAES http://en.wikipedia.org/wiki/CAES) To me, this is "Grid 2.0" technology. You are moving energy from times where you have cheap excess and placing it on the grid in times of expensive need. If we are going to move to a grid with a lot of renewables, technologies like CAES and pumped hydro (https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...) are two necessary ingredients. The primary difference between CAES and pumped hydro is that CAES is cost effective for both medium (50+MW) and large (500+MW) installations, while pumped hydro is cost effective only at large scale (500MW+) installations.
- virmundi 12y ago
  I wish I could find the PDF from a research group on the topic of CAES. Their thesis is that we could generate most of the USA's power by installing solar in the south west. The power would get pushed to the rest of the US and stored in CAES repositories using natural caves. Each cave system should provide 3 days of sustained use for its region. This would allow for power disruptions. I can't recall if they also included natural gas as a fallback incase of protracted outage. It does open us up to a single point of attack, but I thought it was an interesting idea.
- dredmorbius 12y ago
  CAES works, but has some challenges, most notably the Ideal Gas law: PV = nRT That means that as you increase (or decrease) pressure, you increase (or decrease) heat. This affects CAES two ways. On storing high-pressure gas (usually air), you're creating significant heat of compression. In thin-walled structures (e.g., compressed air tanks), this is generally wasted to the environment. In subterranean storage, often in largely spent (but not fully exhausted) natural gas reservoirs (proven high-pressure gas capacity), you risk explosions within the storage reservoir as hot gas enters. On energy recovery, you've got the reverse problem: the expanding air cools rapidly. In most CAES systems, apparently, the solution is to create a combined-form recovery, in which both expanding gas _and_ natural gas combustion (to raise the gas temperature) are used, so recovery isn't fully from the compressed air storage itself. That said: it is among the more promising options, others being pumped hydro (including sea-based pumped hydro), thermal storage, and seawater-based Fischer-Tropsch fuel synthesis (low round-trip efficiency, but excellent scalability and very long-term storage). See: http://www.reddit.com/r/dredmorbius/comments/28nqoz/electrical_fuel_synthesis_from_seawater_older/ http://www.reddit.com/r/dredmorbius/comments/28nqoz/electric... http://www.reddit.com/r/RenewableTech/comments/29t6t7/seawater_pumped_hydro_storage/ http://www.reddit.com/r/RenewableTech/comments/29t6t7/seawat... (Disclaimer: I'm mod of those subs).
schainks 12y ago
I'm seeing a lot of misinformation on this thread, and I think it would be useful to point hacker news at the Electric Power Research Institute (EPRI), which is a cited source in this paper. They are an engineering-based, independent, non-profit research company. And their headquarters is in the "heart" of Silicon Valley next to Xerox... http://www.epri.com/ http://www.epri.com/ Full disclosure: I am not an EPRI employee, but I've read a lot of their papers and presentations. Their research is original and unbaised. Their engineering is pragmatic and chocked full of raw 100% reality. I wish some of the websites people are citing here were talking to places like EPRI first, but instead write sensationalist headlines that hide details and misinform, making sane, coordinated discussion difficult. I suggest hacker news check them out and maybe send some emails to get better information about this proposal and learn more how the grid truly functions politically, economically, and technically.
- spenrose 12y ago
  EPRIs Board of Directors appears to be dominated by executives from large power monopolies: http://www.epri.com/About-Us/Pages/Board-of-Directors.aspx http://www.epri.com/About-Us/Pages/Board-of-Directors.aspx Yes, there are other members, but PG&E does not join groups which accelerate the rollout of renewables (especially distributed renewables); it focuses on slowing them. So your "independent" and "unbiased" assertions are quite misleading.
- dredmorbius 12y ago
  What misinformation and bias are you seeing? EPRI is largely comprised of traditional utilities, it has major operations outside of California, particularly in North Carolina, which is home to much more conservative utilities than PG&E (whose own record is increasingly checkered). EPRI is generally positive source of information, but I would hesitate to call it unbiased in all regards.
naland 12y ago
no need to think about wind, water, and sunlight, first break great suckers —intel and ms.
dredmorbius 12y ago
The California state plan proposal has been getting discussed recently: "How to power California with wind, water and sun (Jacobson and Delucchi)" (http://www.reddit.com/r/RenewableTech/comments/2btow7/how_to_power_california_with_wind_water_and_sun/ http://www.reddit.com/r/RenewableTech/comments/2btow7/how_to...). J&D's proposal for a US national wind, water, and sun energy system: (http://web.stanford.edu/group/efmh/jacobson/Articles/I/sad1109Jaco5p.indd.pdf http://web.stanford.edu/group/efmh/jacobson/Articles/I/sad11...) is one of the more complete such prosals around. See more links on their website: http://web.stanford.edu/group/efmh/jacobson/Articles/I/susenergy2030.html http://web.stanford.edu/group/efmh/jacobson/Articles/I/susen... Recently they've been providing proposals for each of the 50 states: http://www.stanford.edu/group/efmh/jacobson/Articles/I/WWS-50-USState-plans.html http://www.stanford.edu/group/efmh/jacobson/Articles/I/WWS-5.... David McKay's Without the Hot Air (http://www.withouthotair.com/ http://www.withouthotair.com/) is one of the few comparable efforts I'm aware of, though RMI/Amory Lovins Reinventing Fire (http://www.powells.com/biblio/1-9781603585385-0 http://www.powells.com/biblio/1-9781603585385-0) probably belongs in the mix. Also being discussed on reddit: http://www.reddit.com/r/RenewableTech/comments/2d8ptl/a_roadmap_for_repowering_california_for_all/ http://www.reddit.com/r/RenewableTech/comments/2d8ptl/a_road... (Disclaimer: I'm a moderator of that sub).

51 points by ejr 12y ago

You still need a base power plant and few others for controlling the amount of energy in the system. Using only renewable is kind o hard. If we can figure out a way to store energy the way we can access it very quickly with arbitrary output, we could move on to renewables exclusively.

jerven 12y ago
No we need to be able to shed unwanted power. Generation using renewable sources can be over provisioned, and still be economically feasible. Power usage fluctuations are thé key issue to manage. As wind is a very good base load provider. Don't look at capacity factor that is very misleading.
- schainks 12y ago
  > As wind is a very good base load provider. What? Please show us where the wind blows 24 hours a day, 365 days a year, every year. Not being a nay-sayer, but your comment is very misleading. "Good base load provider" means high availability - reliable enough so the lights don't go out. When's the last time you remember a power outage in the US that did not make the news? Yeah, that kind of availability. Outages are rare enough that they make the news when they do happen. Right now, wind cannot provide this kind of "base load" guarantee unless we overbuild a huge amount of capacity and implement a very sophisticated real-time system to manage all the inputs/outputs, and even then you'll be lucky to generate stable baseline load. China's trying right now and having a very difficult time both delivering stable power, and making money doing it[1]. [1] http://www.windpowermonthly.com/article/1171987/analysis---chinese-wind-curtailments-double-2012 http://www.windpowermonthly.com/article/1171987/analysis---c...
  - jerven 12y ago
    What is base load? Its the minimum load required in a network or is it those plants for whom it is uneconomical to go below a certain output. For the first no power plant is truly base load as all plants must shutdown sometimes. So you need to look at a system. So taking into account that in a large area like California it always blows some where, can wind generate the minimal base load at any time. For wind the law of large numbers eventually means that given a per wind turbine capacity factor of 36% a pure wind net achieves 36% capacity factor. If the 36% is the day peak load, then at 18% you are at night low load, considering that wind can be base load. On the second base load is pump it when you got it e.g. because it costs to much to ramp down (coal, nuclear) or because you got the power anyway (wind, day/noon solar) then yes wind is base load. Single wind turbines are not base load power plants, but when you have thousands of them over a large area they start to guarantee with high accuracy a minimal load with very good prediction properties. Of course this ignores economic efficiency, but that depends very much on oil prizes. e.g. The us uses 18 million barrels of oil a day. That means the yearly oil consumption of the US is very roughly equivalent to the volume of oil required to flood Rhode island state one foot deep. Which on the face of it does not seem economically efficient but at the moment it is.
- leccine 12y ago
  What? You have no idea what you are talking about. But anyways, thanks for the downvotes retards.

beloch 12y ago

This paper proposes converting California's power generation over to wind and solar, with electric vehicles and electrically generated hydrogen vehicles replacing all others. All use of fossil fuels and nuclear power is to be phased out. Notably, it suggests that hydroelectric power should be used to balance loads. i.e. It proposes that California's power grid be stabilized with only hydroelectric power as an on-demand source of generation. Firstly, in 2013 California imported 32.7% of it's electricity. California has little control over how this is generated. Of the power used by California, 40.8% is from Natural Gas, 8.1% is hydroelectric, 6.0% is Nuclear, 4.3% is from wind power, 4.2% is geothermal, 2.1% is from biomass, and 1.4% is solar[1]. Natural Gas and Nuclear power are both excellent on-demand sources of power, and currently meet 46.8% of California's electricity requirements. If these power sources are to be phased out, they must be replaced with energy sources that are on-demand. Wind and solar do not fit this description. Hydro does, but quintupling California's hydroelectric capacity will have a huge impact on the environment. This paper greatly underestimates how much on-demand power generation capacity a power grid needs in order to be stable. Side note: California currently derives little of it's electricity from wind or solar power. Electric vehicle batteries carry a high environmental cost to produce, so it is imperative that the energy they are charged with be of renewable origin for any net environmental benefits to be reaped. Given that 40.8% of California's electricity currently comes from natural gas, it's clear that anyone plugging their EV's into California's grid is doing the environment no favors. [1]http://energyalmanac.ca.gov/electricity/electricity_gen_1983-2013.xls http://energyalmanac.ca.gov/electricity/electricity_gen_1983...

schainks 12y ago
I'd like to clear up your terminology a little bit, since the way you use "on demand" actually means two different use-cases. You're referring to "spinning reserve" versus "on-demand" sources of power. "Spinning reserves" are plants that we keep online in a "ready" state, but disconnected from the grid until we need them. "Spinning reserves" are kept online in the case of a failure elsewhere on the grid, or to adapt to load changes throughout the day. These plants are cost-effective for this use case. "On-demand" facilities are plants that have very fast spin-up time, and so they can be brought "online" from a powered-off very quickly. These kinds of plants are also cost-effective to cycle between both states. Natural Gas Combustion Turbines happen to have fast startup time (fast=minutes), and are cost efficient to keep running, so they're used on the grid for both "on demand" and "spinning reserve applications", as it's cheap to cycle them between both states and cheap to keep them spinning (as long as natural gas is cheap). Even better "on demand" sources of power are batteries, since they can be flipped on/off the grid like a lightswitch, but I digress. Nuclear power plants, on the other hand, are awful for "on demand" applications since they take many days, weeks or months to fully power on/power off, and it costs a lot of money to do so. But, they are good as "spinning reserve" facilities, since they produce very cheap electricity once they are online.

timthorn 12y ago

David MacKay's "Without Hot Air" is an excellent investigation of what needs to be done to power the UK. http://www.withouthotair.com/ http://www.withouthotair.com/

schainks 12y ago

I'd like to take a moment to point out another really great "renewable" technology that is a clever arbitrage hack using power prices: Compressed Air Energy Storage. (http://en.wikipedia.org/wiki/CAES http://en.wikipedia.org/wiki/CAES) To me, this is "Grid 2.0" technology. You are moving energy from times where you have cheap excess and placing it on the grid in times of expensive need. If we are going to move to a grid with a lot of renewables, technologies like CAES and pumped hydro (https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...) are two necessary ingredients. The primary difference between CAES and pumped hydro is that CAES is cost effective for both medium (50+MW) and large (500+MW) installations, while pumped hydro is cost effective only at large scale (500MW+) installations.

virmundi 12y ago
I wish I could find the PDF from a research group on the topic of CAES. Their thesis is that we could generate most of the USA's power by installing solar in the south west. The power would get pushed to the rest of the US and stored in CAES repositories using natural caves. Each cave system should provide 3 days of sustained use for its region. This would allow for power disruptions. I can't recall if they also included natural gas as a fallback incase of protracted outage. It does open us up to a single point of attack, but I thought it was an interesting idea.
dredmorbius 12y ago
CAES works, but has some challenges, most notably the Ideal Gas law: PV = nRT That means that as you increase (or decrease) pressure, you increase (or decrease) heat. This affects CAES two ways. On storing high-pressure gas (usually air), you're creating significant heat of compression. In thin-walled structures (e.g., compressed air tanks), this is generally wasted to the environment. In subterranean storage, often in largely spent (but not fully exhausted) natural gas reservoirs (proven high-pressure gas capacity), you risk explosions within the storage reservoir as hot gas enters. On energy recovery, you've got the reverse problem: the expanding air cools rapidly. In most CAES systems, apparently, the solution is to create a combined-form recovery, in which both expanding gas _and_ natural gas combustion (to raise the gas temperature) are used, so recovery isn't fully from the compressed air storage itself. That said: it is among the more promising options, others being pumped hydro (including sea-based pumped hydro), thermal storage, and seawater-based Fischer-Tropsch fuel synthesis (low round-trip efficiency, but excellent scalability and very long-term storage). See: http://www.reddit.com/r/dredmorbius/comments/28nqoz/electrical_fuel_synthesis_from_seawater_older/ http://www.reddit.com/r/dredmorbius/comments/28nqoz/electric... http://www.reddit.com/r/RenewableTech/comments/29t6t7/seawater_pumped_hydro_storage/ http://www.reddit.com/r/RenewableTech/comments/29t6t7/seawat... (Disclaimer: I'm mod of those subs).

schainks 12y ago

I'm seeing a lot of misinformation on this thread, and I think it would be useful to point hacker news at the Electric Power Research Institute (EPRI), which is a cited source in this paper. They are an engineering-based, independent, non-profit research company. And their headquarters is in the "heart" of Silicon Valley next to Xerox... http://www.epri.com/ http://www.epri.com/ Full disclosure: I am not an EPRI employee, but I've read a lot of their papers and presentations. Their research is original and unbaised. Their engineering is pragmatic and chocked full of raw 100% reality. I wish some of the websites people are citing here were talking to places like EPRI first, but instead write sensationalist headlines that hide details and misinform, making sane, coordinated discussion difficult. I suggest hacker news check them out and maybe send some emails to get better information about this proposal and learn more how the grid truly functions politically, economically, and technically.

spenrose 12y ago
EPRIs Board of Directors appears to be dominated by executives from large power monopolies: http://www.epri.com/About-Us/Pages/Board-of-Directors.aspx http://www.epri.com/About-Us/Pages/Board-of-Directors.aspx Yes, there are other members, but PG&E does not join groups which accelerate the rollout of renewables (especially distributed renewables); it focuses on slowing them. So your "independent" and "unbiased" assertions are quite misleading.
dredmorbius 12y ago
What misinformation and bias are you seeing? EPRI is largely comprised of traditional utilities, it has major operations outside of California, particularly in North Carolina, which is home to much more conservative utilities than PG&E (whose own record is increasingly checkered). EPRI is generally positive source of information, but I would hesitate to call it unbiased in all regards.

naland 12y ago

no need to think about wind, water, and sunlight, first break great suckers —intel and ms.

dredmorbius 12y ago

The California state plan proposal has been getting discussed recently: "How to power California with wind, water and sun (Jacobson and Delucchi)" (http://www.reddit.com/r/RenewableTech/comments/2btow7/how_to_power_california_with_wind_water_and_sun/ http://www.reddit.com/r/RenewableTech/comments/2btow7/how_to...). J&D's proposal for a US national wind, water, and sun energy system: (http://web.stanford.edu/group/efmh/jacobson/Articles/I/sad1109Jaco5p.indd.pdf http://web.stanford.edu/group/efmh/jacobson/Articles/I/sad11...) is one of the more complete such prosals around. See more links on their website: http://web.stanford.edu/group/efmh/jacobson/Articles/I/susenergy2030.html http://web.stanford.edu/group/efmh/jacobson/Articles/I/susen... Recently they've been providing proposals for each of the 50 states: http://www.stanford.edu/group/efmh/jacobson/Articles/I/WWS-50-USState-plans.html http://www.stanford.edu/group/efmh/jacobson/Articles/I/WWS-5.... David McKay's Without the Hot Air (http://www.withouthotair.com/ http://www.withouthotair.com/) is one of the few comparable efforts I'm aware of, though RMI/Amory Lovins Reinventing Fire (http://www.powells.com/biblio/1-9781603585385-0 http://www.powells.com/biblio/1-9781603585385-0) probably belongs in the mix. Also being discussed on reddit: http://www.reddit.com/r/RenewableTech/comments/2d8ptl/a_roadmap_for_repowering_california_for_all/ http://www.reddit.com/r/RenewableTech/comments/2d8ptl/a_road... (Disclaimer: I'm a moderator of that sub).