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Solar will supply almost all growth in U.S. electricity generation through 2025

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Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#221

Post by danans »

AnthonyMouse wrote: post #219
danans wrote: post #203

Earlier quoted context omitted.

> What do you do when it runs down, because it's unusually cold or you have an extended period of low generation, or both? I'm not talking about going off grid, just energy price arbitrage. You still have the option of pulling power from the grid to heat your house, although potentially at a higher price. With storage, you could also coordinate grid loads during the night so that at any given time the total load on t…

> I'm not talking about going off grid, just energy price arbitrage. You still have the option of pulling power from the grid to heat your house, although potentially at a higher price. It's not a different problem for the grid. If the grid is generating nearly all of its power from solar and wind and it's calm and cold and night, where does the grid get the power to run your heat pumps? Storage is not only expensive…

> On the coldest week of the decade when everyone's heating system is using 250% more power than usual, and has been for days, the storage runs down and then what?

Since we're talking about the grid of the future, there are several possible options:

- Hydrogen electrolyzed/stored (pressurized or as NH3) during the summer can be used to add supply to the grid.

- Pumped hydro increases its output during the cold snap.

- Power imported from regions that aren't experiencing the same cold snap with no renewable generation.

> If the grid is generating nearly all of its power from solar and wind

Since you said "nearly", there is some room for geothermal, synfuels, and maybe SMRs (if they can ever be built economically).

The point is that we won't have a lack of carbon-free generation sources or storage options in the future.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#222

Post by stcredzero »

AnthonyMouse wrote: post #139
stcredzero wrote: post #129

Earlier quoted context omitted.

Using solar for the air conditioning load in the summer is perfect. Ish. They don't completely correspond.

It's close enough that you can compensate by setting a lower indoor temperature during daylight and letting it rise a few degrees around sunset before the outdoor temperature declines.

Whether it be the thermal battery of the house, or something else, some form of storage or buffering is going to be needed. Therefore, not perfect correspondence.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#223

Post by ETH_start »

tallowen wrote: post #35
verisimi wrote: post #15

I don't get why solar is so popular. In more northern regions, you get much less light in the winter. You effectively can only generate around one tenth of the energy you can in the summer - this is from experience talking to others who monitor their solar installations. But, you need more energy in the winter. People are in more, using electricity for heat cos it's colder. I'm pointing out that there is a supply/dem…

I think solar is becoming popular because it is so much cheaper where it works. One point of disagreement is that you are saying "you need more energy in the winter". Right now, for example, tomato paste is made in a facility that runs year round. The main cost in converting tomatoes into tomato paste is in the thermal cost of energy. Having abundant cheap energy at one time of year will shift the way such industrial…

>Having abundant cheap energy at one time of year will shift the way such industrial processes work so that we use more energy when supply is the highest rather than using the most energy when demand is the highest.

That would require leaving a lot of capital idle, while is itself wasteful from both an economic and environmental perspective.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#224

Post by AnthonyMouse »

danans wrote: post #221
AnthonyMouse wrote: post #219

Earlier quoted context omitted.

> I'm not talking about going off grid, just energy price arbitrage. You still have the option of pulling power from the grid to heat your house, although potentially at a higher price. It's not a different problem for the grid. If the grid is generating nearly all of its power from solar and wind and it's calm and cold and night, where does the grid get the power to run your heat pumps? Storage is not only expensive…

> On the coldest week of the decade when everyone's heating system is using 250% more power than usual, and has been for days, the storage runs down and then what? Since we're talking about the grid of the future, there are several possible options: - Hydrogen electrolyzed/stored (pressurized or as NH3) during the summer can be used to add supply to the grid. - Pumped hydro increases its output during the cold snap.…

> Hydrogen electrolyzed/stored (pressurized or as NH3) during the summer can be used to add supply to the grid.

> Pumped hydro increases its output during the cold snap.

These are essentially other types of storage, and you're trying to go for something where you trade the cost of storage against the cost of the conversion equipment. (It can't be cheaper for both or that's what you'd use all the time.)

The nice thing about batteries is that you can draw power from them as fast as you'd usually ever want to, to the point of discharging the entire battery within 30-60 minutes. A 100kWh battery could give you 200kW for half an hour. And of course then two 100kWh batteries could give you 400kW for half an hour.

Whereas if you have a 100kW generator and 100kWh of NH3, you can generate 100kW. If you have a 100kW generator and 200kWh of NH3, you can generate at 100kW for two hours, but you can't generate 200kW, much less 400kW.

Which kind of leads to the problem here. If you're going to have a 50GW average shortfall for a week, you need 8.4TWh of storage. Ouch. Okay, so that's why we're using the ones with the cheapest storage, but that's still not cheap. And then you need 50,000,000 kW of generation capacity for that type of storage, on top of the storage.

But you're only going to use either of them for one week every two years.

That seems impractical.

> Power imported from regions that aren't experiencing the same cold snap with no renewable generation.

It's not obvious how this one is supposed to work either. Say it's -15 in the Northeast, that's trouble, we'll have to import power from Texas. Where it's also winter, and therefore 25 degrees with significant heating demand, and generation there isn't as low this week but it's below average. Texas can handle that, they charge a higher rate at night, people shift demand enough or lower their thermostats and they can break even. But they have none to spare.

Okay then, the Midwest? Nope, too close to the Northeast, it's -15 there too. The South then. Finally, a region with spare capacity... but it's only 10% of what you need and the Midwest wants it too.

And the general problem with this one is that people are going to optimize it out. If you have cross-continent transmission lines, they'll be used whenever they're useful, which will lower the price of electricity. And then people will build less generation capacity, because it's less needed and less profitable. And then the whole grid has less slack in it and you can't rely on the slack existing in situations like this. See also "just in time" supply chains in an emergency situation.

> Since you said "nearly", there is some room for geothermal, synfuels, and maybe SMRs (if they can ever be built economically).

But this is kind of the point. You don't build geothermal or nuclear plants for periodic use in an unusual supply crunch. If they're enough of the grid to address this, they're that much of the grid all the time.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#225

Post by AnthonyMouse »

stcredzero wrote: post #222
AnthonyMouse wrote: post #139

Earlier quoted context omitted.

It's close enough that you can compensate by setting a lower indoor temperature during daylight and letting it rise a few degrees around sunset before the outdoor temperature declines.

Whether it be the thermal battery of the house, or something else, some form of storage or buffering is going to be needed. Therefore, not perfect correspondence.

It's perfect correspondence in the amount of power required seasonally. You need more air conditioning in the summer because there is more sunlight, which also yields more solar generation. The times also align closely enough that the thermal buffer of the house is all you need, and since that is available, it's a solved problem. Whereas using solar power to provide heat in winter is exactly the opposite.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#226

Post by ClumsyPilot »

defrost wrote: post #195
ClumsyPilot wrote: post #193

Earlier quoted context omitted.

This is literally called magical thinking - there is money in breaking the law of gravity, so what?

Addressing storage | provisioning issues is not breaking the laws of thermodynamics. We're talking aviation industry as a reasonable equivilance here, not magical anti-grav machines. Reddit is really the venue for eponymous comments.

Actually they are exactly the same thing - seasonal storage with efficiency over 50% is basically magical infinite energy battery.

Just like anti-gravity machine, neither breaks the laws of physics, and neither has any known method for an engineer to implement.

Currently, you either need preposterous quantity of batteries, or you are stuck creating synthetic/green fuels at efficiencies of ~20% or less.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#227

Post by ben_w »

switchbak wrote: post #77
megaman821 wrote: post #25

Earlier quoted context omitted.

The answer is a bit simple. Only a small amount of Earth's population lives at north European latitudes ( https://engaging-data.com/population-latitude-longitude/ ). Solar is quite effective for the majority of the population, so its adoption rate will have the biggest impact on further climate change.

I get that it's a great solution for much of the world - and that is fantastic. But they were asking about its effectiveness in northern climates during winter (which I also live in). It sounds like your answer is: "it doesn't work there". If so, that's fine, we can focus on other approaches in such climates. What seems like an emerging shortsighted opinion (on HN at least) is: "it's so cheap, just use more". That do…

Regions that get down to -20 C in a normal winter have a rounding error of the total human population in them, what with humans not functioning too well in such conditions either.

There are three ways you can have winter power with PV when you're close to but south of the arctic circle:

1. more cells, which is basically fine because of the very low population density and the cheap cells.

2. storage, which you have to be careful about regardless, because (no matter how you actually store it) a month's worth of energy supply in stored form is an industrial accident waiting to happen, even if you're storing it as a petrochemical that we already have standards for.

3. transmission, which is basically fine for everyone except Russia and North Korea, because everyone else far from the equator has decent trade relations with someone closer, sometimes (US, China) it's another place inside the same country. And yes, although it would take a while to build, the losses from HVDC are low enough that this makes sense on paper.

> I can't imagine the system you'd have to build to satisfy such demand with solar and battery (or similar) storage in the worst case, but I don't imagine it's "cheap".

Correct, but this is why so few people live in those parts of the world in the first place: getting stuff there, and staying warm there in winter, is and always has been harder.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#228

Post by switchbak »

cycomanic wrote: post #99
switchbak wrote: post #77

Earlier quoted context omitted.

I get that it's a great solution for much of the world - and that is fantastic. But they were asking about its effectiveness in northern climates during winter (which I also live in). It sounds like your answer is: "it doesn't work there". If so, that's fine, we can focus on other approaches in such climates. What seems like an emerging shortsighted opinion (on HN at least) is: "it's so cheap, just use more". That do…

The OP was saying: "I don't get why solar is so popular" based on the fact it doesn't work as well in extreme Northern regions where only a tiny fraction of the world's population lives. That's sort of like saying I don't get why boats/ships are so popular because they can't drive on land.

I literally started with "I get that it's a great solution for much of the world - and that is fantastic." ... so I think I'm on board with what you're saying. I do agree that the OP sounded a little too sour on it though.

And yes, I think we can all agree that Solar works well where .. it works well.

The issue is many folks are pronouncing it as some kind of a panacea. The reality is that there's a lot of places where it's marginal (and needs effective dispatchable fallbacks) and others where it's just not suitable. Luckily there's comparatively few people that live in those places, so it won't make much of a difference on the environmental bottom line. But for folks like me, these distinctions are important.

And "just add more solar" actually isn't a great idea, as it reduces the ROI on each panel, and there's a minimum amount of dispatchable capacity you need to keep online anyway. Sounds like it really does come down to storage at that level, most of which is still progressing to full productization.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#229

Post by ben_w »

AnthonyMouse wrote: post #185
sheepybloke wrote: post #177

Earlier quoted context omitted.

You get a larger market share of the total energy consumption/payments to be during the day. E.g. because solar is cheaper, I shift my usage so that all of my energy costs are during the day, and if a majority of people do that, there will be enough money to keep the businesses afloat.

"Lose money on every kWh but make it up on volume" doesn't actually work. The most electricity should cost at night is approximately what it does now, because you can get that from nuclear or hydro, and why wouldn't you unless you have an alternative that costs less than that? The lowest sustainable daytime price has to pay for the panels, the labor to install them, the land, maintenance, loan interest etc. And a sig…

> The price difference is not going to be a factor of 100, and you'd be lucky to get a factor of 2 and still be able to pay back your costs, no matter how cheap the panels themselves get.

Perhaps not x100, but likely more than you think too, as european domestic PV installation costs were significantly lower than US installation costs last time I compared them.

I'm not sure what installation costs are now, but here in Germany several local supermarkets are selling PV systems you can install yourself on your apartment balcony for €199:

https://www.archyde.com/the-lidl-parkside-solar-panel-review...

I've seen other things like this with batteries for a similar price, though I can't remember the brand or exact specs.

Re: Solar will supply almost all growth in U.S. electricity generation through 2025

#230

Post by wiredfool »

mensetmanusman wrote: post #212
wiredfool wrote: post #157

Earlier quoted context omitted.

Other recent threads have mentioned gridscale battery storage on the order of 8-10c/KWh.

Lithium based is on the order of $100/kWhr: https://thundersaidenergy.com/downloads/battery-storage-cost... .

FWIW, that's a different measure -- the 8-10c/kwh is for amortized cost over the lifetime of energy storage, vs the capital cost to build it.
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