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Random renewable energy-related question that I've been thinking about: Specifically wrt solar, a big argument against is that it can't provide power during th

by bl0b 6y ago

Random renewable energy-related question that I've been thinking about: Specifically wrt solar, a big argument against is that it can't provide power during the night and we don't have a good way to store energy. What I'm wondering is why it's so imperative that residential/commercial properties are able to get full power from the grid 24/7? What if prices for power go way up during the night (because it can't come from solar), and people could just learn to get most of their power from the grid during the day? And have a relatively small per-house battery that charges during the day and can be used at night.

deleted 6y ago
[deleted]
motorcycleman9 6y ago
People prefer to not need to do that.
philips 6y ago
Many energy providers do this and they can provide back pressure to devices like smart thermostats. https://nest.com/energy-partners/ https://nest.com/energy-partners/ The industry for residential distributed energy resource systems and smart pricing is fairly nascent as far as I can tell though.
sparkie 6y ago
> What if prices for power go way up during the night Individual energy providers do not control prices. The market does. If there is market demand for energy at night, then people will fill in the gap to provide it. Anyone pushing up prices at night will have competition from someone else who will undercut them. They'll be forced to drop prices or lose customers. Batteries are inefficient, expensive, and do not provide an adequate amount of electricity for most purposes. Consider a UPS, they're about 90% efficient at most, and for all that 10% of wasted energy, you get to power your computer for about 15-60 minutes if the power is lost. The batteries only last a few years. Also, a bigger argument against solar (at least, photovoltaics) is that they use up rare earth metals, have limited lifetimes (<25 years), and then become non-recyclable toxic waste. Concentrating solar energy is more promising as a sustainable solution, but requires large infrastructure and the right climate to be cost effective.
- pfdietz 6y ago
  "Inefficient" = 90%? I think you need to think more about what you've written there.
  - sparkie 6y ago
    As stated, that is "at most". A usual UPS is 80-89% efficient. Even still, assuming they were 90% efficient, is it worth the extra 10% energy consumption just so you can run your computer for 1 hour at night when the solar energy provider ups their rate? You still need to consume the additional energy in the day to charge the battery. For me to label it efficient, I'd be looking for 95%+, but 99% would be preferable. Remember, this efficiency declines as the battery ages. You only get a few years of efficient use before it declines significantly. Then you have a disposal problem. A typical UPS uses lead-acid batteries, the same type used in cars. They're not environmentally friendly.
    - pfdietz 6y ago
      Of course it's worth it. Losing 10% of the energy in storage is close to trivial, particularly if that energy is otherwise curtailed excess production. It would be worthwhile to use far less efficient storage for long term load leveling, if the capital cost were low enough. Hydrogen with cheap electrolysers and combined cycle turbines might have a round trip efficiency of 33% -- and that would be GREAT as a last component for getting to a fossil-fuel free grid, particularly at high latitude.
      - sparkie 6y ago
        But this is missing the elephant in the living room (this thread), which is nuclear. One of the main issues with nuclear is that it isn't cost effective to turn on/off to meet demand changes in day and night. Nuclear power stations usually only generate energy for the baseload. If we were to cut energy consumption down at night (by increasing costs), the baseload would also drop, and leave an even larger gap to meet for peak, which must be met by other means like solar or fossil fuels. If anything, we want to shift some energy consumption to off-peak times like early hours, so that the baseload is higher and can be met by cheaper nuclear, along with other solutions like tidal. If this happens, the gap between peak and baseload during the day/evening will be smaller, and can be met with solutions like (concentrating) solar which are more environmentally friendly than photovoltaics + batteries.
losteric 6y ago
I think that's one of the ideas behind the Tesla power packs - acting as a power reserve over time.
unchocked 6y ago
Consumers would be better served to direct that investment toward utility scale storage, with advantages including economy of scale. This assumes quality utility management, which may be doubtful. But if we as a society cannot get our collective act together to run modern electrical utilities, distributed storage is a poor band-aid. It's worth noting that a feature of life on unreliable third world utility grids is that people with money spend a lot on redundant generation and storage.
Gibbon1 6y ago
Far as I can tell that argument isn't a technical argument. It's more of a lawyer type argument where you toss out objections and hope one of them sticks. One of my memories was my dad taking me to work after dinner. They were running a wind tunnel. They were scheduled to run it at 9pm but the power company didn't give them the go ahead till 11pm. Which meant they weren't done to 2am. The reason, thing draws close to 200 MW. They ran it at night because it's cheaper. Not because they particularly loved blowing their evening into the late morning. Lot of industrial users are chasing price. Friend of mine has solar panels and lives in Arizona. She and her husband run the air conditioner full tilt in the afternoon off the panels and then turn it off when the sun goes down. Much as I poop on the idea that free market pixie dust is the and only the solution to all of our problems. I would assume this is one it'll solve just fine. Seriously if running your air conditioner costs $1/hr in the afternoon and $5/hr after 8pm, you know what people will do.
tonyarkles 6y ago
One of the fun things I notice whenever the topic of renewables comes up is the assumption that the world around you is hospitable :). We have human populations living in areas where turning off the energy is a miserable experience, in both directions. It’s autumn in Saskatchewan right now. The nights are getting cool enough that we’ve, sadly, had to start the furnace. Within a few months, we’re likely to start getting temperatures that drop to -40 for sustained periods, and drop to around 8h of daylight per day. Power outages in the winter are a very big deal.
pfdietz 6y ago
Battery costs are falling rapidly, and will likely be much lower in ten years when any nuclear power plant started today might come online. Hydrogen electrolyser costs are also falling rapidly, and hydrogen can be stored underground for a per-energy cost two orders of magnitude cheaper than the per-energy cost of batteries.
jillesvangurp 6y ago
The simple solution to that problem is indeed batteries. Currently battery production is growing exponentially. Factories are crossing into the TWH per year territory. That's right now. Batteries are going to be absolutely everywhere. There are going to be millions of EVs on the road and plugged into the grid technically capable to absorb from and deliver energy to the grid. And that's just cars. For reference, one mid size EV with about 50KWH of battery is the equivalent of about 4-5 days of electricity usage for a normal household. 2 million such EVs would provide about 1 TWH of battery capacity, enough to power up to 10 million houses for a day. Now add wind, solar, domestic solar (on your roof, windows) and grid cables to the mix and we are talking about a massive distributed network of periodically (over) producing sites and hundreds of millions of EVs, trucks, grid batteries, and other energy storage solutions capable of either delivering or soaking up or delivering in the order of PWH energy. That's basically happening in the next two decades. So, we won't need gas plants or nuclear plants on the grid long term. Or rather, we might use them if they get much cheaper than they are currently are or are expected to be. Of course, any kind of planning involving today's price levels of battery or electricity cost are probably off by orders of magnitude as clean energy solutions and batteries are still dropping in cost. A 10x drop in price is entirely feasible with improvements in efficiency, mass production, use of cheaper materials, etc. For both solar and battery. There are so many companies working on a wide variety of this kind of improvements that I'd go as far as saying that that 10x drop in price is more a question of when than if. 'When' here is about 2 decades or less. It's the 100x mark that interests me because I believe that's feasible as well but obviously a bit further out. A 100x drop in the price of electricity (measured in $ per KWH) completely and utterly destroys the business case for any form of nuclear currently being planned, considered, or dreamed of. Or rather it reduces it to a niche market for places where it is desirable to have lots of power but impractical to be connected to the grid, lots of batteries, and wind/solar solutions. These places exist of course. But they are far from populated areas. Think remote sites in the arctic, large ships, etc. Small reactors would be awesome for cleaning up the shipping sector. One little snag here is of course that while small reactors are going to be safe, they can be made unsafe rather easily by slapping some explosives to them. You say small reactor, I say dirty bomb waiting to happen. They're kind of hopeless from a safety point of view unless you keep them in a maximum security facility. That makes using them rather expensive.
jabl 6y ago
In many parts of the world there are so-called deregulated electricity markets, where a market operator takes bids for producers and the marginal price then determines the wholesale price for that time period (usually the period being something between 15 minutes and 1 hour). So yes, if the marginal unit that sets the wholesale price is a low marginal cost producer like wind, solar or nuclear, the wholesale price for that period will be very low. Conversely, if demand is very high and the marginal producer is a peaker gas plant, the price will be very high. This is basically the business model behind grid batteries as well. Buy power and charge the batteries when power is cheap, sell the power when it's expensive. One big problem here is that despite wholesale markets working like this for a long time, customer uptake of electricity contracts with time-varying prices tied to the wholesale price has been very poor. In general it seems most customers rather pay a higher fixed electricity price than check the current price before starting their laundry (or something else that takes a decent amount of power).

by bl0b 6y ago

deleted 6y ago

[deleted]

motorcycleman9 6y ago

People prefer to not need to do that.

philips 6y ago

Many energy providers do this and they can provide back pressure to devices like smart thermostats. https://nest.com/energy-partners/ https://nest.com/energy-partners/ The industry for residential distributed energy resource systems and smart pricing is fairly nascent as far as I can tell though.

sparkie 6y ago

> What if prices for power go way up during the night Individual energy providers do not control prices. The market does. If there is market demand for energy at night, then people will fill in the gap to provide it. Anyone pushing up prices at night will have competition from someone else who will undercut them. They'll be forced to drop prices or lose customers. Batteries are inefficient, expensive, and do not provide an adequate amount of electricity for most purposes. Consider a UPS, they're about 90% efficient at most, and for all that 10% of wasted energy, you get to power your computer for about 15-60 minutes if the power is lost. The batteries only last a few years. Also, a bigger argument against solar (at least, photovoltaics) is that they use up rare earth metals, have limited lifetimes (<25 years), and then become non-recyclable toxic waste. Concentrating solar energy is more promising as a sustainable solution, but requires large infrastructure and the right climate to be cost effective.

pfdietz 6y ago
"Inefficient" = 90%? I think you need to think more about what you've written there.
- sparkie 6y ago
  As stated, that is "at most". A usual UPS is 80-89% efficient. Even still, assuming they were 90% efficient, is it worth the extra 10% energy consumption just so you can run your computer for 1 hour at night when the solar energy provider ups their rate? You still need to consume the additional energy in the day to charge the battery. For me to label it efficient, I'd be looking for 95%+, but 99% would be preferable. Remember, this efficiency declines as the battery ages. You only get a few years of efficient use before it declines significantly. Then you have a disposal problem. A typical UPS uses lead-acid batteries, the same type used in cars. They're not environmentally friendly.
  - pfdietz 6y ago
    Of course it's worth it. Losing 10% of the energy in storage is close to trivial, particularly if that energy is otherwise curtailed excess production. It would be worthwhile to use far less efficient storage for long term load leveling, if the capital cost were low enough. Hydrogen with cheap electrolysers and combined cycle turbines might have a round trip efficiency of 33% -- and that would be GREAT as a last component for getting to a fossil-fuel free grid, particularly at high latitude.
    - sparkie 6y ago
      But this is missing the elephant in the living room (this thread), which is nuclear. One of the main issues with nuclear is that it isn't cost effective to turn on/off to meet demand changes in day and night. Nuclear power stations usually only generate energy for the baseload. If we were to cut energy consumption down at night (by increasing costs), the baseload would also drop, and leave an even larger gap to meet for peak, which must be met by other means like solar or fossil fuels. If anything, we want to shift some energy consumption to off-peak times like early hours, so that the baseload is higher and can be met by cheaper nuclear, along with other solutions like tidal. If this happens, the gap between peak and baseload during the day/evening will be smaller, and can be met with solutions like (concentrating) solar which are more environmentally friendly than photovoltaics + batteries.

losteric 6y ago

I think that's one of the ideas behind the Tesla power packs - acting as a power reserve over time.

unchocked 6y ago

Consumers would be better served to direct that investment toward utility scale storage, with advantages including economy of scale. This assumes quality utility management, which may be doubtful. But if we as a society cannot get our collective act together to run modern electrical utilities, distributed storage is a poor band-aid. It's worth noting that a feature of life on unreliable third world utility grids is that people with money spend a lot on redundant generation and storage.

Gibbon1 6y ago

Far as I can tell that argument isn't a technical argument. It's more of a lawyer type argument where you toss out objections and hope one of them sticks. One of my memories was my dad taking me to work after dinner. They were running a wind tunnel. They were scheduled to run it at 9pm but the power company didn't give them the go ahead till 11pm. Which meant they weren't done to 2am. The reason, thing draws close to 200 MW. They ran it at night because it's cheaper. Not because they particularly loved blowing their evening into the late morning. Lot of industrial users are chasing price. Friend of mine has solar panels and lives in Arizona. She and her husband run the air conditioner full tilt in the afternoon off the panels and then turn it off when the sun goes down. Much as I poop on the idea that free market pixie dust is the and only the solution to all of our problems. I would assume this is one it'll solve just fine. Seriously if running your air conditioner costs $1/hr in the afternoon and $5/hr after 8pm, you know what people will do.

tonyarkles 6y ago

One of the fun things I notice whenever the topic of renewables comes up is the assumption that the world around you is hospitable :). We have human populations living in areas where turning off the energy is a miserable experience, in both directions. It’s autumn in Saskatchewan right now. The nights are getting cool enough that we’ve, sadly, had to start the furnace. Within a few months, we’re likely to start getting temperatures that drop to -40 for sustained periods, and drop to around 8h of daylight per day. Power outages in the winter are a very big deal.

pfdietz 6y ago

Battery costs are falling rapidly, and will likely be much lower in ten years when any nuclear power plant started today might come online. Hydrogen electrolyser costs are also falling rapidly, and hydrogen can be stored underground for a per-energy cost two orders of magnitude cheaper than the per-energy cost of batteries.

jillesvangurp 6y ago

The simple solution to that problem is indeed batteries. Currently battery production is growing exponentially. Factories are crossing into the TWH per year territory. That's right now. Batteries are going to be absolutely everywhere. There are going to be millions of EVs on the road and plugged into the grid technically capable to absorb from and deliver energy to the grid. And that's just cars. For reference, one mid size EV with about 50KWH of battery is the equivalent of about 4-5 days of electricity usage for a normal household. 2 million such EVs would provide about 1 TWH of battery capacity, enough to power up to 10 million houses for a day. Now add wind, solar, domestic solar (on your roof, windows) and grid cables to the mix and we are talking about a massive distributed network of periodically (over) producing sites and hundreds of millions of EVs, trucks, grid batteries, and other energy storage solutions capable of either delivering or soaking up or delivering in the order of PWH energy. That's basically happening in the next two decades. So, we won't need gas plants or nuclear plants on the grid long term. Or rather, we might use them if they get much cheaper than they are currently are or are expected to be. Of course, any kind of planning involving today's price levels of battery or electricity cost are probably off by orders of magnitude as clean energy solutions and batteries are still dropping in cost. A 10x drop in price is entirely feasible with improvements in efficiency, mass production, use of cheaper materials, etc. For both solar and battery. There are so many companies working on a wide variety of this kind of improvements that I'd go as far as saying that that 10x drop in price is more a question of when than if. 'When' here is about 2 decades or less. It's the 100x mark that interests me because I believe that's feasible as well but obviously a bit further out. A 100x drop in the price of electricity (measured in $ per KWH) completely and utterly destroys the business case for any form of nuclear currently being planned, considered, or dreamed of. Or rather it reduces it to a niche market for places where it is desirable to have lots of power but impractical to be connected to the grid, lots of batteries, and wind/solar solutions. These places exist of course. But they are far from populated areas. Think remote sites in the arctic, large ships, etc. Small reactors would be awesome for cleaning up the shipping sector. One little snag here is of course that while small reactors are going to be safe, they can be made unsafe rather easily by slapping some explosives to them. You say small reactor, I say dirty bomb waiting to happen. They're kind of hopeless from a safety point of view unless you keep them in a maximum security facility. That makes using them rather expensive.

jabl 6y ago

In many parts of the world there are so-called deregulated electricity markets, where a market operator takes bids for producers and the marginal price then determines the wholesale price for that time period (usually the period being something between 15 minutes and 1 hour). So yes, if the marginal unit that sets the wholesale price is a low marginal cost producer like wind, solar or nuclear, the wholesale price for that period will be very low. Conversely, if demand is very high and the marginal producer is a peaker gas plant, the price will be very high. This is basically the business model behind grid batteries as well. Buy power and charge the batteries when power is cheap, sell the power when it's expensive. One big problem here is that despite wholesale markets working like this for a long time, customer uptake of electricity contracts with time-varying prices tied to the wholesale price has been very poor. In general it seems most customers rather pay a higher fixed electricity price than check the current price before starting their laundry (or something else that takes a decent amount of power).