I think the future will be robust national/international grids, with a mixture of storage options (batteries/pumped hydro) to smooth out the intermittent nature of wind and solar.
Cynics always talk about the amount of energy storage required for solar as if you need to store 24 hours of energy for solar/wind to be viable.
I'd like to see numbers on having 1 hour of storage for peak demand, a robust national grid, and appropriately provisioned and placed solar and wind, taking the duck curve into consideration.
Even achieving just one hour of storage globally amounts to 2.5 TWh of storage. By comparison the entire world produces ~300 GWh worth of lithium ion battery annually. That leaves geographically limited options like pumped hydroelectricity, and solutions not yet deployed at any significant scale like hydrogen fuel cells, synthetic methane, thermal batteries, flywheels, etc.
Realistically we should saturate daytime energy demand with solar, and if there aren't any scalable storage options by then switch gears and proceed with hydroelectric where it's viable and nuclear where it's not.
>By comparison the entire world produces ~300 GWh worth of lithium ion battery annually.
And this will increase a hundredfold to make EV production possible.
That means that if 10% of production goes to stationary storage then within 10 years, we'll have 10 full global hours of storage.
If there's serious demand then the supply will scale up to create it.
Also, old EV batteries will provide plenty of extra stationary storage. Not to mention batteries still in EVs, in a pinch.
Realistically we won't throw insane amounts of storage at the problem. We'll make demand more flexible so it does work when electricity is cheap and eases off when it becomes more expensive.
For instance, something like heating: why store the electricity for heating? Wouldn't it make more sense for a house to have some form of heavily-insulated thermal mass that it can massively heat when electricity is dirt cheap, then tap into at midnight without drawing power? Storing heat is cheap, you just need a giant block of concrete with solid insulation. You don't need fancy nanoscale tech like with lithium-ion.
Even something like a kettle: the hot water taps you see at companies that are pre-heated. Have a home-version. Insulate the shit out of that and do 90% of the boiling with peak electricity.
And that's not even touching industrial power usage.
Trying to ape past systems that were based on flat electricity prices just seems like a failure of imagination. Of course it would be expensive, but why the heck would you even want to?
> Even achieving just one hour of storage globally amounts to 2.5 TWh of storage. By comparison the entire world produces ~300 GWh worth of lithium ion battery annually
... so if we could increase battery production by just 10x, then we could create an hours worth of storage every year. That seems... very doable.
>Even achieving just one hour of storage globally amounts to 2.5 TWh of storage. By comparison the entire world produces ~300 GWh worth of lithium ion battery
What's the point of this comparison?
Lithium ion batteries are probably the least cost effective means of dealing with intermittency. It's also rare that the entire world is without wind and sun simultaneously.
I would imagine the approach to store the energy would be to use the energy from solar panels to do work that can be used to produce electricity later.
For example, you could use solar energy to pump water back uphill to flow down through a hydro electric dam later.
Even if it isn't the most efficient, in the long run it would likely provide the best scalability and least long term environmental impact. Once you have the facility in place, the same water could be pumped uphill to flow back down a million times over with the only overhead replacing water lost through evaporation and maintaining the facility.
Am I missing something that makes such an approach unfeasible?
I suspect most of the intermittency of wind and solar will be addressed through super-capacity (500% of peak demand, not 100%) and geographic diversity. Batteries will be used for very short-term local balancing and power regulation ... then for those occasional times when hydro, wind and solar don’t cut it, we’ll still burn a little gas but it will be bio gas or green hydrogen, rather than fossil gas. This gas will be expensive, but these plants will hardly ever run.
I agree entirely. I chose the 1 hour of storage as a number because I had to say something, and I didn't want to go to low as it would undoubtedly knee jerk responses of "that's not enough, you need X hours".
The main point I was going for is that we shouldn't think of a national network in the same way as we think of a off grid house with solar, where you have to deal with many hours without sunlight, and have storage capacity for several days of rain.
In a similar vein, the intermittency of solar and wind look bad when you look at isolated generation instances, but when you have a continent spanning network, the intermittency is reduced as the wind is always blowing somewhere, and the sun is shining for many more hours than when you look at any single point on map.
Again, I would love to see the numbers if you were plan out a realistic build out of this ideal network. It would probably be a pretty big number, but how would it compare to building out with nuclear, or even just lots of coal power plants from scratch.
Super-capacity is going to be a major driver for the build-out of water electrolysis for the production of hydrogen. You can turn what will basically be a waste product into a highly useful fuel. I've seen people contend that this will be expensive, but given the very cheap input costs I believe this will be a very cheap process.
Europe didn't want to act when russia invaded crimea, because russia supplied all the gas. Being dependent on your neighbors for your electricity supply and having no backup would only make this problem worse.
I wonder what the limits are on transmitting power around the world? Like, if we wanted to connect Northern Africa to the North American power grid, how feasible would it be, and what would the losses and power capacity be?
It seems that with all the interest in using ReBCO tape in tokomaks due to its ability to transmit more power at higher temperatures than the materials that preceded it (used, for example in ITER) that it could be used to transmit power over long distances. Has anyone actually done it yet, or is it just too expensive? (Apparently the current capacity of superconducting cable is finite; if you run too much current through it, it'll transition to becoming non-superconducting. So maybe the amount of ReBCO tape needed per unit of power or the amount of active cooling needed makes it impractical.)
Eventually, to be able to usefully transmit power from daytime sun to nighttime will require crossing oceans. Which I imagine would be tough to do with a cable has to be actively cooled and work for many years without maintenance. Maybe for my hypothetical North America to North Africa route, you'd run a superconducting cable down through Central and South America over to Brazil, then have a normal high-voltage DC line across the Atlantic, with another superconducting cable that crosses the Sahara.
I dunno, back of the envelope says you'd only lose 33% with today's HVDC lines from North Africa to North America. The ocean will sink the lost energy for us. And we can make up the difference with more solar/wind, which is cheap.
Superconducting would be nice to have, but doesn't seem necessary.
It's not cynicism, it's understanding capacity factors and how difficult large scale storage is. If solar panels have a capacity factor of around .25, which is what we're seeing in real installations worldwide, then it is necessary to overproduce by at least 4x and store it somewhere for off-peak solar production hours.
It's even worse if there is not other dispatchable generation available unless people are willing to accept periodic blackouts.
We're in the process of building out a combined solar and battery installations in Guam, which is about the ideal case with predictable weather, predictable load, little heavy industry and low potential for load growth. It'll enable them to retire all their old fuel oil generators, but they'll be keeping the diesel/LNG plant for at least the next 30 years even if they only run it a few days worth of time every month.
That Guam use case would be perfect to trial combined desal and hydrogen production and storage for production troughs instead of keeping the diesel genny. Saltwater and renewables goes in, clean water and hydrogen come out.
So I've been watching these Van build outs into full time living vans for travel. Most of them have solor panels on the roof, and 3 two hundred watt batteries. One guy said it would take him 23 days to fully charge these batteries off of solar vs just a few hours to charged them from the alternator when he is driving. It just doesn't seem very practical at this point. They all seem to have 2 or 3 thousand watt panels on the roof. Is he correct? How does the math work here? How long should it take for a 1000 Watt panel to charge a two hundred watt battery?
I think that your recollection is incomplete or garbled. Modern solar panels are about 20% efficient. They can generate about 200 watts per square meter in midday sun with clear skies. 2000 to 3000 watts of panels would be about 10-15 square meters (107-161 square feet). Do these vans actually have roofs that large, completely covered with panels?
You might expect roof top panels with sub-optimal orientation to generate about 12.5% of their peak rating when averaged over a year. That would be 375 watts, annualized, from a system with a peak capacity of 3000 watts. There is no van-portable battery system currently on the market that can store 375 * 24 * 23 = 207,000 watt-hours. (For comparison, the Tesla Model S battery stores 100,000 watt-hours.)
My guess is that you are not correctly recalling how much solar capacity these vans have installed. When I Google for van life solar I get guides and kits referencing much less power.
uses a single 150 watt panel. Based on the photo the article includes, I don't think that the van rooftop has room for more than 3 panels of this type.
If solar were free, but we still needed to pay for battery storage, how would it then compare in cost to fuel-based alternatives (fossil fuel, nuclear etc)?
Might be of interest to you: the think tank Rethinkx is forecasting wind and solar + lithium ion batteries will be cheaper than continuing to run already existing coal and gas power plants by 2030. They believe this will cause the capital invested in other types of power plants to become "stranded".
And even simpler: electric heat pump water heaters, which already coat about the same as has water heaters to operate, and also serve as dispatchable one way energy storage for intermittent renewables.
It's a little hard to predict how the price of battery storage will change as demand for it increases by orders of magnitude, and also how energy usage patterns will change as the relative cost of nighttime energy usage goes up. I've explored these themes in the past in a number of notes.
David MacKay wrote a wonderful and highly accessible overview of the topic in 02009 as part of his excellent book, Sustainable Energy Without the Hot Air, which is specifically about sustainable energy in Britain. Unfortunately it needs to be updated—in particular, it doesn't consider utility-scale battery facilities at all—and he is sadly no longer in a position to update it. The license does permit third parties to provide an updated version, but he did not publish the source code. Still, here it is: https://www.withouthotair.com/c26/page_186.shtml
...how energy usage patterns will change as the relative cost of nighttime energy usage goes up.
My fondest dream is that they'll stop dotting the countryside with those ridiculous pole-mounted "security" lights, and we'll be able to experience nighttime again.
Using batteries for all storage use cases is bad engineering. Hydrogen can be stored underground for $1/kWh of energy storage capacity (there is also a per-kW cost, but it is independent of the size of the underground storage caverns). Use that (burned in turbines) instead of batteries for the rare correlated outages of solar/wind, and the cost goes down.
People use way too much power for battery storage to be viable. The average household consumes 28.9kwh in a day (in 2017), which is way more than rooftop solar can provide.
Maybe when we have smaller houses and don't have a bajillion devices plugged in all the time.
It's amazing how much less of something you use when you don't have basically an endless, cheap supply of it. You tend to conserve a lot more because you know it's finite and will run out if you use too much.
> The average household consumes 28.9kwh in a day, which is way more than rooftop solar can provide.
The average house doesn't need to source 100% of their electricity from rooftop solar. Electric utilities are how most people will still get a significant portion of their electricity, even those with rooftops solar.
Also, the average household's electricity needs could be reduced significantly while increasing comfort via better insulation, air sealing, and higher efficiency appliances.
Once solar generating costs are further reduced, there needs to be improved effort on improving local infrastructure (within a single residence). Getting rid of DC-AC-DC conversion would be a huge improvement. If we standardize on a DC system (48v?) then household devices can be more efficient without the conversions.
In a northern latitude, it looks like I could (more than) meet my electric use with ~1/2 of the southern face of my roof (so like 25% of the roof area).
An additional benefit of solar is that it is the most politically stable energy source since it can be deployed off-grid. This is important because the more unstable regions of the world can sometimes be seen as hopeless because investments require high upfront costs and can't be trusted with being properly maintained. Therefore solar can enable growth and be deployed during periods of unrest/conflict.
What if instead of pulling carbon above ground, we inject oxygen underground, produce electricity and CO2 below ground and then leave the CO2 down there. Has anyone tried this?
This is more or less what post-combustion capture carbon-capture-and-storage plants do, with the minor detail that they do the actual combustion above ground instead of below ground. But the inputs and outputs are as you describe: oxygen from the air, fossil fuels from underground, CO₂ outputs injected back underground, heat outputs sent to somewhere unspecified, typically the air.
CCS power stations are substantially more expensive than the usual kind of fossil-fuel power station, and they are generally considered to be economically uncompetitive.
It's probably better to do the actual combustion aboveground in many cases—although it makes your power plants easier to blow up with bombs, it also makes them enormously easier to build and maintain, and much less dangerous to work in when nobody is trying to blow them up.
Economically uncompetitive compared to solar/wind 500% overbuilt? How many hours storage have to be added to the solar / wind to make a ccs gas plant competitive?
This is good to hear. I assume location must play a large part in this? Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska.
I sometimes wonder if the widespread adoption of solar is going to have an environmental impact that isn't immediately apparent. Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn means that plant can't absorb carbon from the atmosphere. So unless we just limit ourselves to rooftop solar panels there's sure to be some sort of environmental impact if we just switch all our energy to solar.
> Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska.
I don't think this was your intention, but this reminded me of something I see in so many of these conversations.
In discussions about solar (and electric cars) there are always people who say "well this won't work in situation X", with an unsaid implication of "this is not the solution".
It is unlikely that we will find a single solution that will be a good fit for all situations. Instead we will have many tools in our belt and apply accordingly.
I know that you used alaska as an extreme, perhaps they will never get off fossil fuels. But alaska is a tiny population overall. Its the main population centers that we need to worry about, not the extremes that are hand picked to be difficult.
I've read a few articles that these solar farms are creating their own microclimates, and particularly in already warm areas can have significant impacts to wildlife with the local temperature increasing in the range of 3-4 degrees C: https://www.nature.com/articles/srep35070
“A total of 173,000 terawatts (trillions of watts) of solar energy strikes the Earth continuously. That's more than 10,000 times the world's total energy use“
That article is from 2011, but I think it’s a very safe bet that factor is still more than 1,000 today.
Also, I would think about every solar panel you put on the ground reflects less energy into space than the ground did.
I've wondered about that too (competing with nature for the sun) but I think just putting panels on the roof or over the parking lot would probably address 95% of the problem.
Along similar lines, I've wondered if solar panels will start to look like pine trees at some point.
>I've wondered if solar panels will start to look like pine trees at some point.
Interesting thought, but I'm not sure there same factors that led to plant evolution will play out with solar panels. Plants reaching up into the air was a direct response to competition with other types of plants. Presumably the same sort of competition won't be necessary with solar panels. I'm sure nature still has a lot of inspiration we can draw from for creating new types of solar panels, but my guess is that the most efficient surface for collecting solar energy is the flat square design we see today.
> I assume location must play a large part in this? Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska.
Yes, each peak kilowatt of utility-scale solar produces about 240 watts average in Arizona, 140 in Maine, and 100 in Germany ("capacity factors" of 24%, 14%, and 10%). I assume the number for Alaska would be even lower.
> Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn means that plant can't absorb carbon from the atmosphere.
Yes, and also it will reflect less heat back into space than the plant or bare dirt would, locally raising the temperature. These will start to be important problems when the quantity of power produced by solar panels is about 100 times larger than current world marketed energy consumption. I expect that this will happen in about 30 years. However, merely switching all our energy to solar will have an effect that's about 100 times too small to matter.
> Yes, each peak kilowatt of utility-scale solar produces about 240 watts average in Arizona, 140 in Maine, and 100 in Germany ("capacity factors" of 24%, 14%, and 10%). I assume the number for Alaska would be even lower.
In this US government report [1] that looks at solar energy in remote parts of Alaska the capacities of 11 systems in use in 11 villages they looked at ranged from 7.1% to 11.6%. Looks like around 9.4% average.
> it will reflect less heat back into space than the plant or bare dirt would, locally raising the temperature
I'm not sure this checks out... the light gets absorbed, but the energy doesn't get turned into heat, it gets turned into electricity. If anything, where it's covering up concrete or asphalt it should reduce the conversion of sunlight to local heat.
> These will start to be important problems when the quantity of power produced by solar panels is about 100 times larger than current world marketed energy consumption. I expect that this will happen in about 30 years.
You predict energy needs will increase 100x in 30 years? Surely you mean just solar energy production?
One possibility is to use farmland or grazing land. You can pick crops that do better in part shade and then place solar panels over them. If done right it could have a beneficial effect on crop growth while at the same time earning extra money.
This is a allowed but semi-rare technique in Japan. Rare because of the capital costs to built the panels. Certain high end plants, such as tea, prefer the shade.
I like to believe that millions of years ago the people of Saturn made giant solar collection tree-like space elevator power facilities to catch all those passing rays. That is where Saturn’s rings came from.
The intermittent problem is the one that worries me the most.
As an engineer, if I think really long term, I would like to couple water storage with energy storage. I think water will itself need to be stored in a better manner. And I would store it in tunnels at different heights. And optimize that height difference for maximum potential energy.
The tunneling tech would advance faster when it serves both of these functions and things like Hyperloop.
It doesn't matter that solar itself is cheap, it still needs backup plants which are the reason Germany has the highest electricity prices - world-wide.
It's really strange that users on HN keep rehashing the myth that solar and wind energy will result in lower electricity prices for consumers - they won't, never.
Even if solar and wind energy was free, consumers would still have to pay the costs for running backup and/or storage plants which lets consumers prices soar.
The problem with solar and wind is that they simply can't produce electricity on-demand which means the kWh has an actual market value and can therefore be sold with a profit.
If a solar or wind park produces huge amounts of electricity when demand is low, the result are dumping or even negative prices.
Affordable and clean electricity in populous industrial countries like Germany or the US can be provided through nuclear energy only.
Here is a commercial installation of solar + storage at $0.04/kWh[1]. And it’s not unique, that article links to the cheapest solar + storage in the US at $0.025/kWh.
Additionally, these are today’s prices, as per this article the price for renewables is dropping exponentially every year. And if Elon Musk is to be believed (which I do) the price for storage is also dropping exponentially.
storage alone will almost never be enough. The electricity is just too important for the modern societies to leave it to chance. You will have events where there will be no wind or sun for weeks. In order to have that many batteries it would require monumental investments. And those batteries would sit unused for years.
You need a diverse and distributed generation network, backed by gas burning plants.
Right now the grids in Texas go negative from an over abundance of wind power, and California regularly pays to get rid of peak power during the duck curve. It’s cheap, and also not very valuable.
The stable, high-duty cycle of a power plant is very valuable per kWh, and what renewables must compete against. Maybe someday we’ll get cheap versions of that through new battery inventions, but that day is definitely not today or the near future. There’s only one carbon free way to get it at scale.
German electricity is dirt cheap if your business qualifies for tax exemptions. Consumers have to pay all the renewable energy taxes and they get higher as the spot market price drops.
Readit News
Cynics always talk about the amount of energy storage required for solar as if you need to store 24 hours of energy for solar/wind to be viable.
I'd like to see numbers on having 1 hour of storage for peak demand, a robust national grid, and appropriately provisioned and placed solar and wind, taking the duck curve into consideration.
Realistically we should saturate daytime energy demand with solar, and if there aren't any scalable storage options by then switch gears and proceed with hydroelectric where it's viable and nuclear where it's not.
And this will increase a hundredfold to make EV production possible.
That means that if 10% of production goes to stationary storage then within 10 years, we'll have 10 full global hours of storage.
If there's serious demand then the supply will scale up to create it.
Also, old EV batteries will provide plenty of extra stationary storage. Not to mention batteries still in EVs, in a pinch.
Realistically we won't throw insane amounts of storage at the problem. We'll make demand more flexible so it does work when electricity is cheap and eases off when it becomes more expensive.
For instance, something like heating: why store the electricity for heating? Wouldn't it make more sense for a house to have some form of heavily-insulated thermal mass that it can massively heat when electricity is dirt cheap, then tap into at midnight without drawing power? Storing heat is cheap, you just need a giant block of concrete with solid insulation. You don't need fancy nanoscale tech like with lithium-ion.
Even something like a kettle: the hot water taps you see at companies that are pre-heated. Have a home-version. Insulate the shit out of that and do 90% of the boiling with peak electricity.
And that's not even touching industrial power usage.
Trying to ape past systems that were based on flat electricity prices just seems like a failure of imagination. Of course it would be expensive, but why the heck would you even want to?
... so if we could increase battery production by just 10x, then we could create an hours worth of storage every year. That seems... very doable.
What's the point of this comparison?
Lithium ion batteries are probably the least cost effective means of dealing with intermittency. It's also rare that the entire world is without wind and sun simultaneously.
In terms of cost:
Demand shaping < overproduction < pumped storage < < lithium ion batteries
I would imagine the approach to store the energy would be to use the energy from solar panels to do work that can be used to produce electricity later.
For example, you could use solar energy to pump water back uphill to flow down through a hydro electric dam later.
Even if it isn't the most efficient, in the long run it would likely provide the best scalability and least long term environmental impact. Once you have the facility in place, the same water could be pumped uphill to flow back down a million times over with the only overhead replacing water lost through evaporation and maintaining the facility.
Am I missing something that makes such an approach unfeasible?
https://en.m.wikipedia.org/wiki/Flow_battery
Dead Comment
The main point I was going for is that we shouldn't think of a national network in the same way as we think of a off grid house with solar, where you have to deal with many hours without sunlight, and have storage capacity for several days of rain.
In a similar vein, the intermittency of solar and wind look bad when you look at isolated generation instances, but when you have a continent spanning network, the intermittency is reduced as the wind is always blowing somewhere, and the sun is shining for many more hours than when you look at any single point on map.
Again, I would love to see the numbers if you were plan out a realistic build out of this ideal network. It would probably be a pretty big number, but how would it compare to building out with nuclear, or even just lots of coal power plants from scratch.
Europe didn't want to act when russia invaded crimea, because russia supplied all the gas. Being dependent on your neighbors for your electricity supply and having no backup would only make this problem worse.
It seems that with all the interest in using ReBCO tape in tokomaks due to its ability to transmit more power at higher temperatures than the materials that preceded it (used, for example in ITER) that it could be used to transmit power over long distances. Has anyone actually done it yet, or is it just too expensive? (Apparently the current capacity of superconducting cable is finite; if you run too much current through it, it'll transition to becoming non-superconducting. So maybe the amount of ReBCO tape needed per unit of power or the amount of active cooling needed makes it impractical.)
Eventually, to be able to usefully transmit power from daytime sun to nighttime will require crossing oceans. Which I imagine would be tough to do with a cable has to be actively cooled and work for many years without maintenance. Maybe for my hypothetical North America to North Africa route, you'd run a superconducting cable down through Central and South America over to Brazil, then have a normal high-voltage DC line across the Atlantic, with another superconducting cable that crosses the Sahara.
Superconducting would be nice to have, but doesn't seem necessary.
It's even worse if there is not other dispatchable generation available unless people are willing to accept periodic blackouts.
We're in the process of building out a combined solar and battery installations in Guam, which is about the ideal case with predictable weather, predictable load, little heavy industry and low potential for load growth. It'll enable them to retire all their old fuel oil generators, but they'll be keeping the diesel/LNG plant for at least the next 30 years even if they only run it a few days worth of time every month.
You might expect roof top panels with sub-optimal orientation to generate about 12.5% of their peak rating when averaged over a year. That would be 375 watts, annualized, from a system with a peak capacity of 3000 watts. There is no van-portable battery system currently on the market that can store 375 * 24 * 23 = 207,000 watt-hours. (For comparison, the Tesla Model S battery stores 100,000 watt-hours.)
My guess is that you are not correctly recalling how much solar capacity these vans have installed. When I Google for van life solar I get guides and kits referencing much less power.
For example, this guide:
https://www.genericvan.life/2018/04/30/complete-vanlife-sola...
uses a single 150 watt panel. Based on the photo the article includes, I don't think that the van rooftop has room for more than 3 panels of this type.
https://youtu.be/6zgwiQ6BoLA
Play with the assumptions and find out.
https://dercuano.github.io/topics/solar.html and in particular https://dercuano.github.io/notes/energy-storage-efficiency.h..., https://dercuano.github.io/notes/heliogen.html, and https://dercuano.github.io/notes/lithium-supplies.html. https://dercuano.github.io/notes/balcony-battery.html and https://dercuano.github.io/notes/the-suburbean.html explore the question at the household scale.
More recently, https://news.ycombinator.com/item?id=26219344 and https://news.ycombinator.com/item?id=26229595 explore this question in more detail, and https://news.ycombinator.com/item?id=26308189 explores specifically what it would cost for California to switch to an all-solar grid with only battery storage over the next decade.
David MacKay wrote a wonderful and highly accessible overview of the topic in 02009 as part of his excellent book, Sustainable Energy Without the Hot Air, which is specifically about sustainable energy in Britain. Unfortunately it needs to be updated—in particular, it doesn't consider utility-scale battery facilities at all—and he is sadly no longer in a position to update it. The license does permit third parties to provide an updated version, but he did not publish the source code. Still, here it is: https://www.withouthotair.com/c26/page_186.shtml
My fondest dream is that they'll stop dotting the countryside with those ridiculous pole-mounted "security" lights, and we'll be able to experience nighttime again.
Maybe when we have smaller houses and don't have a bajillion devices plugged in all the time.
Maybe in the USA.
> which is way more than rooftop solar can provide.
Maybe in your part of the world this is true, but it is not unrealistic in many places.
Also, why are you limiting your thinking to rooftop solar?
The average house doesn't need to source 100% of their electricity from rooftop solar. Electric utilities are how most people will still get a significant portion of their electricity, even those with rooftops solar.
Also, the average household's electricity needs could be reduced significantly while increasing comfort via better insulation, air sealing, and higher efficiency appliances.
It wouldn't be enough for winter heating though.
CCS power stations are substantially more expensive than the usual kind of fossil-fuel power station, and they are generally considered to be economically uncompetitive.
It's probably better to do the actual combustion aboveground in many cases—although it makes your power plants easier to blow up with bombs, it also makes them enormously easier to build and maintain, and much less dangerous to work in when nobody is trying to blow them up.
I sometimes wonder if the widespread adoption of solar is going to have an environmental impact that isn't immediately apparent. Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn means that plant can't absorb carbon from the atmosphere. So unless we just limit ourselves to rooftop solar panels there's sure to be some sort of environmental impact if we just switch all our energy to solar.
I don't think this was your intention, but this reminded me of something I see in so many of these conversations.
In discussions about solar (and electric cars) there are always people who say "well this won't work in situation X", with an unsaid implication of "this is not the solution".
It is unlikely that we will find a single solution that will be a good fit for all situations. Instead we will have many tools in our belt and apply accordingly.
I know that you used alaska as an extreme, perhaps they will never get off fossil fuels. But alaska is a tiny population overall. Its the main population centers that we need to worry about, not the extremes that are hand picked to be difficult.
“A total of 173,000 terawatts (trillions of watts) of solar energy strikes the Earth continuously. That's more than 10,000 times the world's total energy use“
That article is from 2011, but I think it’s a very safe bet that factor is still more than 1,000 today.
Also, I would think about every solar panel you put on the ground reflects less energy into space than the ground did.
Along similar lines, I've wondered if solar panels will start to look like pine trees at some point.
Interesting thought, but I'm not sure there same factors that led to plant evolution will play out with solar panels. Plants reaching up into the air was a direct response to competition with other types of plants. Presumably the same sort of competition won't be necessary with solar panels. I'm sure nature still has a lot of inspiration we can draw from for creating new types of solar panels, but my guess is that the most efficient surface for collecting solar energy is the flat square design we see today.
Yes, each peak kilowatt of utility-scale solar produces about 240 watts average in Arizona, 140 in Maine, and 100 in Germany ("capacity factors" of 24%, 14%, and 10%). I assume the number for Alaska would be even lower.
> Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn means that plant can't absorb carbon from the atmosphere.
Yes, and also it will reflect less heat back into space than the plant or bare dirt would, locally raising the temperature. These will start to be important problems when the quantity of power produced by solar panels is about 100 times larger than current world marketed energy consumption. I expect that this will happen in about 30 years. However, merely switching all our energy to solar will have an effect that's about 100 times too small to matter.
In this US government report [1] that looks at solar energy in remote parts of Alaska the capacities of 11 systems in use in 11 villages they looked at ranged from 7.1% to 11.6%. Looks like around 9.4% average.
[1] https://www.energy.gov/sites/prod/files/2016/02/f29/Solar-Pr...
I'm not sure this checks out... the light gets absorbed, but the energy doesn't get turned into heat, it gets turned into electricity. If anything, where it's covering up concrete or asphalt it should reduce the conversion of sunlight to local heat.
You predict energy needs will increase 100x in 30 years? Surely you mean just solar energy production?
It's a combination of solar, wind, and hydrogen (with a little battery storage).
As an engineer, if I think really long term, I would like to couple water storage with energy storage. I think water will itself need to be stored in a better manner. And I would store it in tunnels at different heights. And optimize that height difference for maximum potential energy.
The tunneling tech would advance faster when it serves both of these functions and things like Hyperloop.
> https://www.globalpetrolprices.com/electricity_prices/
It's really strange that users on HN keep rehashing the myth that solar and wind energy will result in lower electricity prices for consumers - they won't, never.
Even if solar and wind energy was free, consumers would still have to pay the costs for running backup and/or storage plants which lets consumers prices soar.
The problem with solar and wind is that they simply can't produce electricity on-demand which means the kWh has an actual market value and can therefore be sold with a profit.
If a solar or wind park produces huge amounts of electricity when demand is low, the result are dumping or even negative prices.
Affordable and clean electricity in populous industrial countries like Germany or the US can be provided through nuclear energy only.
Proof:
> https://ourworldindata.org/grapher/ghg-emissions-by-sector?t...
> https://ourworldindata.org/grapher/ghg-emissions-by-sector?t...
Germany: 350 million tons p.a. CO2 in the energy sector France: 50 million tons p.a. CO2 in the energy sector
Germany: 38 cents per kWh France: 22 cents per kWh
Germany: 50% renewables in its electricity mix France: 70% nuclear in its electricity mix
Cost of a simple cycle gas turbine powerplant: $400/kW (combined cycle, $1000/kW)
Go ahead and back up those renewables. It's still less expensive than installing nuclear, even if the turbines burn renewable-derived hydrogen.
Additionally, these are today’s prices, as per this article the price for renewables is dropping exponentially every year. And if Elon Musk is to be believed (which I do) the price for storage is also dropping exponentially.
[1] https://pv-magazine-usa.com/2019/09/10/los-angeles-commissio...
You need a diverse and distributed generation network, backed by gas burning plants.
The stable, high-duty cycle of a power plant is very valuable per kWh, and what renewables must compete against. Maybe someday we’ll get cheap versions of that through new battery inventions, but that day is definitely not today or the near future. There’s only one carbon free way to get it at scale.