4 ms·

I don't understand what you mean by that. Could you explain?

jacquesm 11y ago
Scotland (and other countries besides) has a lot of 'pumped storage', lakes at a relatively high point that are fed from lakes at a lower point by running pumps that push the water from the lower lake to the higher one when energy is cheap and then back into the grid when it is more expensive (when there is a scarcity). The net effect of this is that electricity originally generated by nuclear plants and other fossil fuel plants gets 'converted' into (more expensive!) 'green' energy. It's a kind of white-washing for electrons. The price difference can be substantial more than making up for the cost of the pumping and subsequent re-generation. And of course it's the energy sold to the public that matters, not how it was originally generated so by double counting this energy it changes the balance considerably without there actually being more renewable energy to begin with.
- teh_klev 11y ago
  Sure, but during a suitably windy night who's to say that a good number of those electrons used to refill pumped storage schemes aren't sourced from wind farms?
- protomyth 11y ago
  I thought the whole point of pumped storage was to use solar / wind to do the pumping and release the water back (thus running the turbines) when it was dark or not windy. Why are they using nuclear or fossil fuels?
  - maxerickson 11y ago
    The owners of coal and nuclear plants are the ones that paid for the pumped storage, they had the idea of making their plant operations more efficient, not of storing renewable energy. This is one of the early large ones, built by the local utilities: https://www.consumersenergy.com/content.aspx?id=6985 https://www.consumersenergy.com/content.aspx?id=6985
  - jacquesm 11y ago
    Yes, that's another use. But when it is favorable economically speaking then fossil fuels and nuclear will be used as well. The pumps don't care what color the electrons are. It's mostly a matter of bookkeeping and less one of technology. And as long as demand for electricity during peak times does not coincide with the point in the day when the peak amount of electricity is generated this is a nice way to make some money for the operators.
  - seren 11y ago
    I am not sure about coal, but you can't easily shutdown a nuclear reactor, so there are times during the day when you are overproducing. So pumping some water is a way to not totally lose the energy produced during that time.
    - jacquesm 11y ago
      Shutting down a nuclear reactor can be done very fast (emergency shutdown, underload shutdown) but increasing the load takes much longer. This is one of the reasons that the blackout of 2003 lasted as long as it did, due the rapid decrease in load a couple of nuclear plants did a rapid shut-down. Most base-load generating plants are difficult to adjust to a rapidly varying load.
      - Retric 11y ago
        You could set a bypass around the generators to the cooling tower to reduce energy production without reducing the rate of nuclear reactions. They don't do this for a number of reasons which basically boil down to nuclear fuel being cheap so they would much rather shut down just about everything else. This does create a minor issue if the grid fails, but that’s a rare event and doing an actual shutdown is considered safer.
        jacquesm 11y ago
        Ah, so that's the reason. I actually wondered about this after the 2003 event, I was caught right in the middle of it and had plenty of reason for reflection on the theme of power generation (that plus a lifelong interest in renewables also caused me to look into the various alternatives).
      - logfromblammo 11y ago
        "Neutron poisons" that accumulate in fuel rods during normal operation can also interfere with a re-start. Sometimes a shutdown core has to sit for a few weeks to let those reaction poisons decay before it even becomes possible to sustain a controlled chain reaction in that core again.
- liotier 11y ago
  No, pumped storage is not "white-washing" : energy storage is the key piece to making unpredictable energy sources viable, by storing during low demand and having a buffer instantly available to respond to peaks. It displaces having extremely expensive gas turbines on standby or lighting up fuel burners during peak loads, so it has a direct impact on reducing fossil fuel consumption.
  - jacquesm 11y ago
    Of course it is. The arbitrage is what makes it happen because that's what makes it profitable. If the energy so generated were labeled with the point of origin then it would count as fossil fuel and then it would yield less on the energy market. The load variations are not such that the generating capacity could not be reduced in time, but there is less money in that. This is not renewable energy though it masquerades as such. Note that before green energy became a thing this was already happening so it is simply a re-labeling rather than that these lakes suddenly got re-purposed for renewable energy storage. If the source of the electricity is not originally renewable energy then it is deceptive to sell it as such. People pay a pretty premium for renewable energy.
    - msandford 11y ago
      > Of course it is. Not necessarily! It may be, it may not be. It depends on the time and place and whatnot. Pumped hydro today might be mostly "white washing" today in Scotland. It might not be "white washing" tomorrow in Germany. It depends on a lot of factors. If the electrical rates do occasionally go negative in mainland Europe (from wind) and there are pumped hydro stations there then it's entirely possible that the wind electrons are the ones pushing the water uphill rather than the fossil fuel electrons, and then when that water eventually does generate electricity again, it's technically still renewable. https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroelectric_power_stations https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroel... It sounds like the plant that you visited in Scotland was white washing, at least when you visited. But that doesn't mean that all pumped hydro everywhere in the world definitely, for sure, guaranteed, is also doing the same.
    - 11y ago
- teh_klev 11y ago
  Scotland only has one pumped storage scheme (Cruachan). It's annual generation was only 705 Gwh (as at 2009), which is only 13% of total hydro generation. Sure there might be "green electron" washing going on, but it's probably not significant. https://en.wikipedia.org/wiki/Cruachan_Power_Station https://en.wikipedia.org/wiki/Cruachan_Power_Station
  - jacquesm 11y ago
    I visited the station a few years ago and it is the reason for my original comment, at the time this was explained in some detail by one of the people on the tour. Very impressive by the way and highly recommended if you're in the region. As for the bookkeeping: A certain amount of electricity is produced using renewables which is always < the current baseload. It is then (much) more profitable to sell this energy to consumers directly and then to use the reduced base load requirements to top off the lakes before reducing base load generation capacity. At night the process reverses and now the 'newly minted green electrons' get added to the green energy already being sold. This makes more money than selling the nuclear/coal/NG generated electricity directly even though there is some loss from the whole pumping operation. Note that the scheme already made money based on the demand pricing of electricity, the 'green' aspect simply made it more profitable.
    - teh_klev 11y ago
      I too have visited it and can highly recommend visiting as well. My dad worked on its construction.
      - jacquesm 11y ago
        http://pics.camarades.com/v/jacques/trips/scotland08/dscf1584.jpg.html http://pics.camarades.com/v/jacques/trips/scotland08/dscf158... Awesome trip, we took a mini clubman (the real deal) to Scotland.
        teh_klev 11y ago
        Excellent. If you're interested in the history of hydro electric in Scotland I can thoroughly recommend "The Dam Builders: Power from the Glens": http://www.amazon.co.uk/dp/1841582255 http://www.amazon.co.uk/dp/1841582255 Also this chap has a fairly good bunch of images and maps of various scheme throughout Scotland, apparently blagging his way into some facilities to take photographs: http://www.corestore.org/hydro.htm http://www.corestore.org/hydro.htm It's a bit "Web 1.0" but there's some interesting stuff to look at if you like that sort of thing (which I do :) )
- jsingleton 11y ago
  Pumped storage is typically reported separately from Hydro. So much so that Hydro is officially referred to as "Non-pumped storage Hydro". Pumped isn't included as a renewable because the energy mix will depend on when it's recharging as a consumer of the grid. Typically this is overnight so usually nuclear power and wind is used as coal and gas spin down then. Currently both pumped and hydro are making up about 1% of the UK grid each: http://www.gridwatch.templar.co.uk http://www.gridwatch.templar.co.uk It's only useful to think about it in the short term as long term it adds nothing. It just functions as a buffer. You can go round one in Wales: http://www.electricmountain.co.uk http://www.electricmountain.co.uk
- danmaz74 11y ago
  > The net effect of this is that electricity originally generated by nuclear plants and other fossil fuel plants gets 'converted' into (more expensive!) 'green' energy. In some situations, even pumped storage storing non-renewable power power is "greener" than you seem to imply. The problem is that nuclear generators can't stop producing electricity when it's not needed; let's say you are France and a large part of your electricity is generated with nuclear power. If you can't store your energy, during the night you're producing power that you need to waste away. And during peak hours, you need to turn on many gas turbines to get additional power. If instead you can store your additional energy during the night, and use that one during peak hours, you burn less fuel and pollute less.
- pjc50 11y ago
  By "a lot" we mean "two power stations for a maximum of 0.7GW and 16GWH": http://www.withouthotair.com/c26/page_191.shtml http://www.withouthotair.com/c26/page_191.shtml

Scotland (and other countries besides) has a lot of 'pumped storage', lakes at a relatively high point that are fed from lakes at a lower point by running pumps that push the water from the lower lake to the higher one when energy is cheap and then back into the grid when it is more expensive (when there is a scarcity). The net effect of this is that electricity originally generated by nuclear plants and other fossil fuel plants gets 'converted' into (more expensive!) 'green' energy. It's a kind of white-washing for electrons. The price difference can be substantial more than making up for the cost of the pumping and subsequent re-generation. And of course it's the energy sold to the public that matters, not how it was originally generated so by double counting this energy it changes the balance considerably without there actually being more renewable energy to begin with.

teh_klev 11y ago
Sure, but during a suitably windy night who's to say that a good number of those electrons used to refill pumped storage schemes aren't sourced from wind farms?
protomyth 11y ago
I thought the whole point of pumped storage was to use solar / wind to do the pumping and release the water back (thus running the turbines) when it was dark or not windy. Why are they using nuclear or fossil fuels?
- maxerickson 11y ago
  The owners of coal and nuclear plants are the ones that paid for the pumped storage, they had the idea of making their plant operations more efficient, not of storing renewable energy. This is one of the early large ones, built by the local utilities: https://www.consumersenergy.com/content.aspx?id=6985 https://www.consumersenergy.com/content.aspx?id=6985
- jacquesm 11y ago
  Yes, that's another use. But when it is favorable economically speaking then fossil fuels and nuclear will be used as well. The pumps don't care what color the electrons are. It's mostly a matter of bookkeeping and less one of technology. And as long as demand for electricity during peak times does not coincide with the point in the day when the peak amount of electricity is generated this is a nice way to make some money for the operators.
- seren 11y ago
  I am not sure about coal, but you can't easily shutdown a nuclear reactor, so there are times during the day when you are overproducing. So pumping some water is a way to not totally lose the energy produced during that time.
  - jacquesm 11y ago
    Shutting down a nuclear reactor can be done very fast (emergency shutdown, underload shutdown) but increasing the load takes much longer. This is one of the reasons that the blackout of 2003 lasted as long as it did, due the rapid decrease in load a couple of nuclear plants did a rapid shut-down. Most base-load generating plants are difficult to adjust to a rapidly varying load.
    - Retric 11y ago
      You could set a bypass around the generators to the cooling tower to reduce energy production without reducing the rate of nuclear reactions. They don't do this for a number of reasons which basically boil down to nuclear fuel being cheap so they would much rather shut down just about everything else. This does create a minor issue if the grid fails, but that’s a rare event and doing an actual shutdown is considered safer.
      - jacquesm 11y ago
        Ah, so that's the reason. I actually wondered about this after the 2003 event, I was caught right in the middle of it and had plenty of reason for reflection on the theme of power generation (that plus a lifelong interest in renewables also caused me to look into the various alternatives).
    - logfromblammo 11y ago
      "Neutron poisons" that accumulate in fuel rods during normal operation can also interfere with a re-start. Sometimes a shutdown core has to sit for a few weeks to let those reaction poisons decay before it even becomes possible to sustain a controlled chain reaction in that core again.
liotier 11y ago
No, pumped storage is not "white-washing" : energy storage is the key piece to making unpredictable energy sources viable, by storing during low demand and having a buffer instantly available to respond to peaks. It displaces having extremely expensive gas turbines on standby or lighting up fuel burners during peak loads, so it has a direct impact on reducing fossil fuel consumption.
- jacquesm 11y ago
  Of course it is. The arbitrage is what makes it happen because that's what makes it profitable. If the energy so generated were labeled with the point of origin then it would count as fossil fuel and then it would yield less on the energy market. The load variations are not such that the generating capacity could not be reduced in time, but there is less money in that. This is not renewable energy though it masquerades as such. Note that before green energy became a thing this was already happening so it is simply a re-labeling rather than that these lakes suddenly got re-purposed for renewable energy storage. If the source of the electricity is not originally renewable energy then it is deceptive to sell it as such. People pay a pretty premium for renewable energy.
  - msandford 11y ago
    > Of course it is. Not necessarily! It may be, it may not be. It depends on the time and place and whatnot. Pumped hydro today might be mostly "white washing" today in Scotland. It might not be "white washing" tomorrow in Germany. It depends on a lot of factors. If the electrical rates do occasionally go negative in mainland Europe (from wind) and there are pumped hydro stations there then it's entirely possible that the wind electrons are the ones pushing the water uphill rather than the fossil fuel electrons, and then when that water eventually does generate electricity again, it's technically still renewable. https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroelectric_power_stations https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroel... It sounds like the plant that you visited in Scotland was white washing, at least when you visited. But that doesn't mean that all pumped hydro everywhere in the world definitely, for sure, guaranteed, is also doing the same.
  - 11y ago
teh_klev 11y ago
Scotland only has one pumped storage scheme (Cruachan). It's annual generation was only 705 Gwh (as at 2009), which is only 13% of total hydro generation. Sure there might be "green electron" washing going on, but it's probably not significant. https://en.wikipedia.org/wiki/Cruachan_Power_Station https://en.wikipedia.org/wiki/Cruachan_Power_Station
- jacquesm 11y ago
  I visited the station a few years ago and it is the reason for my original comment, at the time this was explained in some detail by one of the people on the tour. Very impressive by the way and highly recommended if you're in the region. As for the bookkeeping: A certain amount of electricity is produced using renewables which is always < the current baseload. It is then (much) more profitable to sell this energy to consumers directly and then to use the reduced base load requirements to top off the lakes before reducing base load generation capacity. At night the process reverses and now the 'newly minted green electrons' get added to the green energy already being sold. This makes more money than selling the nuclear/coal/NG generated electricity directly even though there is some loss from the whole pumping operation. Note that the scheme already made money based on the demand pricing of electricity, the 'green' aspect simply made it more profitable.
  - teh_klev 11y ago
    I too have visited it and can highly recommend visiting as well. My dad worked on its construction.
    - jacquesm 11y ago
      http://pics.camarades.com/v/jacques/trips/scotland08/dscf1584.jpg.html http://pics.camarades.com/v/jacques/trips/scotland08/dscf158... Awesome trip, we took a mini clubman (the real deal) to Scotland.
      - teh_klev 11y ago
        Excellent. If you're interested in the history of hydro electric in Scotland I can thoroughly recommend "The Dam Builders: Power from the Glens": http://www.amazon.co.uk/dp/1841582255 http://www.amazon.co.uk/dp/1841582255 Also this chap has a fairly good bunch of images and maps of various scheme throughout Scotland, apparently blagging his way into some facilities to take photographs: http://www.corestore.org/hydro.htm http://www.corestore.org/hydro.htm It's a bit "Web 1.0" but there's some interesting stuff to look at if you like that sort of thing (which I do :) )
jsingleton 11y ago
Pumped storage is typically reported separately from Hydro. So much so that Hydro is officially referred to as "Non-pumped storage Hydro". Pumped isn't included as a renewable because the energy mix will depend on when it's recharging as a consumer of the grid. Typically this is overnight so usually nuclear power and wind is used as coal and gas spin down then. Currently both pumped and hydro are making up about 1% of the UK grid each: http://www.gridwatch.templar.co.uk http://www.gridwatch.templar.co.uk It's only useful to think about it in the short term as long term it adds nothing. It just functions as a buffer. You can go round one in Wales: http://www.electricmountain.co.uk http://www.electricmountain.co.uk
danmaz74 11y ago
> The net effect of this is that electricity originally generated by nuclear plants and other fossil fuel plants gets 'converted' into (more expensive!) 'green' energy. In some situations, even pumped storage storing non-renewable power power is "greener" than you seem to imply. The problem is that nuclear generators can't stop producing electricity when it's not needed; let's say you are France and a large part of your electricity is generated with nuclear power. If you can't store your energy, during the night you're producing power that you need to waste away. And during peak hours, you need to turn on many gas turbines to get additional power. If instead you can store your additional energy during the night, and use that one during peak hours, you burn less fuel and pollute less.
pjc50 11y ago
By "a lot" we mean "two power stations for a maximum of 0.7GW and 16GWH": http://www.withouthotair.com/c26/page_191.shtml http://www.withouthotair.com/c26/page_191.shtml