What is the real limit of expanding solar+wind power?

Hmm yes let's see how things have been going.

electricity-prod-source-stacked (1).png

It's clearer in relative terms, betting on the green coloured wedge isn't doing too well, all those orange and dark blue wedges are expanding past it! Oh no!

electricity-prod-source-stacked.png



Well maybe it'll turn around soon, let's ask the experts at the IEA where things are heading.

Oh what's that? It's to be explosive growth? Renewables collectively overtake coal as the largest source of electricity by 2027, driven entirely by solar and wind?

Screenshot_2023_0104_034543.jpg


Huh, weird.

And the acceleration is pretty widely projected to continue well beyond that until most electricity is renewables in a couple decades? Haven't they heard the pronouncements from 2005 about land area? Have they NO FEAR OF INTERMITTENCY. Don't they know only that little chunk of dark green can do the job.
 
Of course they are not. The only pipe dream is human survival if we don't.

But in order for us to achieve proper decarbonization atomic energy needs to be a large and indeed the dominant part of the package. It's simply the only one that actually fulfills our requirements of easy scalability with minimum environmental impact and minimal environmental requirements. Renewable energy sources like hydro, solar and wind are all nice to have but they simply do not scale as well as atomic due to the large environmental impact of setting them up and their reliance on environmental conditions to work. So they will always be at best a supplemental source of energy.

And unfortunately you are right that right now public opinion and certain very misguided lobbies in the green sector are preventing us from actually using it properly. Which is why my opinion on the future of mankind is grim in this respect.

Australia should show if decarbonization without atomic power can work.
A nice, big, isolated island with plenty of land and a strong green lobby.
No reserve currency to just print money and import at will.

Check out the price data $/MWh this year.

I'm not sure what this price data is signaling.
It seemed steady enough back in 2015, but this year it seems to be whipsawing up and down?
Might be the war and covid.
Or continuing to add new power lines out to all the renewables. :dunno:

I find it hard to think there would be a statistically hard limit of 25% or whatever number, even if as an observable tendency I would be hesitant to chalk it up as being divine mathematical prohibition rather than local fluctuations in political will, economic cost, and innate environmental factors.

A good point! :D
Yes, I picked 20% because it seemed like going above this number for wind+solar would cause exploding costs as multiple technological problems began manifesting and the grand total of all the energy returned vs. energy invested declined.
Divine mathematical prohibition heh.

Ultimately, the physics question stops mattering when the energy returned vs. energy invested goes above 1.
Wind and solar do produce more energy than they take.
So this whole thing is a matter of economics yes. :)

The environmentalists insist carbon polluters are fundamentally destroying the planet, which appears to be quite right.
We have to get rid of the carbon!


Take the more pessimistic assessment.

We switch to 100% solar + wind and our standard of living drops because we need energy returned to be 7 times higher than what we invested and wind+solar with storage technology is below this.
So why not just use nuclear power to produce the windmills and solar panels?
If we don't need a lot of nuclear power plants, then they can be put in only a few places where people will feel safest.

I think a majority Solar+Wind world is possible with Nuclear power and Hydro helping.
If we can just find a good way to store electricity at a huge scale.

An atomic power plant can be built anywhere. It has no special requirements for construction or operation. And it is utterly independent of all environmental conditions short of a meteor impact. And it produces huge amounts of energy in a very small footprint. Atomic has all the benefits of traditional power generation with none of the downsides.

Nuclear power needs a big source of water nearby for cooling purposes.
 
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I'm not sure what this price data is signaling.
It seemed steady enough back in 2015, but this year it seems to be whipsawing up and down?
Might be the war and covid.
Or continuing to add new power lines out to all the renewables.


Yeah it's partly the war with the loss of Russian trade driving world hydrocarbon prices up and thus domestic prices. Natural gas is heavily exposed to export prices, coal is also impacted by this.

Notably Western Australia which isn't on the NEM has legislated protections for domestic supply against world gas prices, and the ACT whose supply is mostly covered by contract-for-difference 100% net renewable purchases, haven't seen these rises.

The other big factor is a coal power availability crisis, over the period of the critical price spikes a lot of coal plants were either genuinely offline or were "offline" for electricity spot market manipulation reasons. The market operator ended up suspending the market and directly controlling bidding and load matching for a few periods.

(Note that this is wholesale price of energy in the electricity market only, any transmission induced price rises would be a margin paid by retailers and retail customers, and not included in this. They would also be a steady step change applied on July 1 each year in most states, not wild day to day fluctuations)
 
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There's always plenty of space somewhere else.


So answer me this, as I assume you would have good information on the subject.
Let's say someone offered a farmer or a rancher to lease long term 1 acre for every 200 or so acres they have under production, to plant a windmill on. So long as that 1 acre had access to a road of some sort. What would the windmill builder have to pay the farmer or rancher for the farmer or rancher to be better off than they are now?
 
I mean most of them just have cows or whatever in and around them anyway yeah. Big open flat plains with gentle inclines are great for wind resources and also tend to be under some sort of agricultural or pastoral production.

cowes.PNG
 
They called me crazy 7 years ago. :old:
Obama Declares War on Coal June 2nd | Page 4 | CivFanatics Forums


I thought that solar + wind power can't go above 20% of an interconnected power grid without disaster.
(If a country consumes 10000MWh in a year, they better not get above 2000MWh from wind+solar)

Wind + Solar are fundamentally unreliable power sources.
(I like reliable hydro power, so I don't count it towards the 20% figure even if it is renewable energy)

I don't care if a country is 60% Wind+Solar if they are hooked up to another country that supplies it with endless amounts of power on cloudly and windless days.


Let's see where we were in 2020 since that is good data.

Europe-27 - Solar+Wind 19%
(All the countries connect together into effectively one power grid with various levels of connectivity)
EU Power Sector 2020 | Electricity Trends | Ember (ember-climate.org)

USA - Solar+Wind 11.6%
(All the lower 48 states, except Texas, connect together into an eastern and western power grid)
(*I can't figure out how to pull Texas out of that 11.6%. The real number should be a bit lower than 11.6% for the lower 48 states)
Renewables = 20.6% of US Electricity in 2020 - CleanTechnica

Texas - Solar+Wind 25%
Graphic Shows What Percentage of Texas' Energy Is Renewable (newsweek.com)

Australia - Solar+Wind 18%
Electricity generation | energy.gov.au



If my theory is correct, as of 2020 Texas should be a permanent yearly disaster.
Europe and Australia should be flirting with electricity problems.


I think this is currently an unresolvable problem.
Experiments where a third or a quarter of the grid run on this stuff, I can't make it work with my feeble brain.
Solar could be fixed if the entire world was connected into 1 power grid perhaps. :hmm:
Or if it was in space being beamed down.
Wind power could be fixed if there was a cheap way to store all that energy somehow at a massive scale.


I made this thread because this article here told me I'm quite wrong. :mad:
Three Myths About Renewable Energy and the Grid, Debunked - Yale E360



Gah!

We just have to use ___(has not been invented yet)___ gigantic amounts of cheap energy storage technology and we can build a power grid out of wind+solar in the next few years.

Surface Area!
 
So answer me this, as I assume you would have good information on the subject.
Let's say someone offered a farmer or a rancher to lease long term 1 acre for every 200 or so acres they have under production, to plant a windmill on. So long as that 1 acre had access to a road of some sort. What would the windmill builder have to pay the farmer or rancher for the farmer or rancher to be better off than they are now?
Sometimes! Windmills work better. But some of them are trying solar. The footprint on the land of solar farms is heavier. May as well be a parking lot.
 
Sometimes! Windmills work better. But some of them are trying solar. The footprint on the land of solar farms is heavier. May as well be a parking lot.





That's the whole point. You can dual use land by building all your solar over parking lots. So no land is actually used up. All the land is still in use for it's previous use.


 
Well, yes. I rather like that solution for solar. Not the "somewhere else" solution as it plays out.





I look around, and I see row crop monocultures and windmills farther than I can see. And yet there are ever more creative explanations for why, in order to save the land, we must intensify its use even more. Now rather than monocropping it and erecting wind towers, we must claim the sunfall itself. Always in the name of progress, ever bottomless - hunger.
 
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Making a solar roof is going to be a significantly higher unit cost than putting them on the ground. As in, if you look at the per-unit cost, it will be a real percentage. Nevermind whether maintenance is more costly.

The land underneath would have to be productive to compensate. If it is, then it's a fairly simple calculation as to whether it should be roofed, left alone, or replaced with ground-level solar.

Solar on fairly desolate lands would be interesting from an ecosystem perspective, because it would add to the ecosystem diversity in the form of novel habitats. There's no way a solar farm is going to be actually a significant unit of space relative to what a 'desolate land' would be.

We also need the scalable technologies to be exportable. Westerners need to decarbonize much faster than they are, but the rest of the world needs to add a lot of energy infrastructure and supply. The best thing we could do for the climate is get the renewables to naturally out-compete coal. That means subsidizing R&D.
 
Yeah utility solar farms are generally just going to be on flat low value land with a lot of sun that nobody wants to use for anything else, that's the practicalities of it. The largest tend to be in desert or arid areas with little alternative use, like Bhadla here in the Thar desert in India, which is about 20km square, which was otherwise not being used for anything.

bhadla.PNG


The largest US ones are in the desert southwest, near Calexico, near Boulder City in Nevada, etc. The largest in Australia is on rural freehold in arid low intensity grazing land, pressed up against a state forest and a coal mine. They end up in such dry areas partly for insolation obviously, but also just that there's unused land available for basically nothing and solar farm geographic needs are a little less finnicky than more locally variable wind resources.

I'm not sure why people are talking like solar plants are about to start swamping actual farmland when that's just not what's happening. Land currently being used has higher values than prospective plants can find elsewhere. Solar farms aren't some hypothetical future possibility, they're a thing which exist now and have pretty solid requirements and economics governing them. I think this is another example of the electricity sector being talked about on the basis of vague feelpinions, and stuff nobody in the sector has thought since like 2005.

Honestly "the solar farms and wind turbines will take over all the land" has roughly the vibe of "trains will go too fast and people will have heart attacks from the speed".
 
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Making a solar roof is going to be a significantly higher unit cost than putting them on the ground. As in, if you look at the per-unit cost, it will be a real percentage. Nevermind whether maintenance is more costly.

The land underneath would have to be productive to compensate. If it is, then it's a fairly simple calculation as to whether it should be roofed, left alone, or replaced with ground-level solar.

Solar on fairly desolate lands would be interesting from an ecosystem perspective, because it would add to the ecosystem diversity in the form of novel habitats. There's no way a solar farm is going to be actually a significant unit of space relative to what a 'desolate land' would be.

We also need the scalable technologies to be exportable. Westerners need to decarbonize much faster than they are, but the rest of the world needs to add a lot of energy infrastructure and supply. The best thing we could do for the climate is get the renewables to naturally out-compete coal. That means subsidizing R&D.


The positive externalities of solar over parking or other structures is that it lowers fuel/cooling costs for those other structures. And saves a lot of gasoline. So there's a lot of cost offset.
 
Also since you're providing that solar electricity for car charging, it just has to be competitive with electricity coming out of mains sockets, which is pretty spenno
 
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The positive externalities of solar over parking or other structures is that it lowers fuel/cooling costs for those other structures. And saves a lot of gasoline. So there's a lot of cost offset.

That would effectively be adding to the productivity (adding is the same as subtracting a negative) to the land underneath. After that, as long as the externalities align with the incentives, it could be a boost for sure.

We will watch it happen in real time, because the more obvious the specific case is, the more likely it is to happen. The advantage of solar over nuclear is also that small players can do small things for small rewards and affect the aggregate due to the number of players.
 
i know it's from july, but parts of the op baffles me. there's no real correlation between the % of the power grid and the feasibility of the thing. understand that oil and coal is still massive, active investments by the goverments in all listed cases. the % is low not because of feasibility, but because of choice.

it's like me punching you in the face and then saying it's inevitable and practical because it happened.
 
there's no real correlation between the % of the power grid and the feasibility of the thing
I don't understand this at all.

I can see a grid alternate between 22% -> 55% renewable energy one day, then 26% -> 48% the next day and ponder what that will look like when even more wind and solar get added.
Negative prices, exploding prices, the demand and supply of electricity have to match at all times.
 
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You're pretty continually mixing up instantaneous power mix at a point in time, and aggregate percentage shares of generation over a year. They don't necessarily have a lot to do with each other.

To the basic issue though, you're misinterpreting the existence of fluctuation itself as a crisis. Nothing about moment to moment fluctuation implies anything is broken, wrong or unfeasible. Demand varies a lot over the course of the day, week, year and always has done. As a result, power sources coming online and offline constantly has long been a thing, driven by weather factors, demand levels, and supply changes due to outages or maintenance. All that switching activity happens at the behest of the central operator and that's been how grids have operated for a long time.

Go back 20 years to when there was no renewable energy in some places and you could still describe certain fuel sources as moving like this over the course of a day:

between 22% -> 55% renewable energy one day, then 26% -> 48% the next day

South Australia, which is now all wind and gas, used to be all coal and gas, and the gas would have regularly gone from basically zero to 50% over the course of a single day.

Against this backdrop, variable generation based on wind and sun is just a new variable which helps determine the need for dispatched power. It shifts the market by reducing the market share for less flexible sources (note that coal fired power getting outcompeted is strictly a good thing too), and it changes how much hedging different generators need to do in futures markets, but that's all pretty standard stuff anyway.
 
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I thought that solar + wind power can't go above 20% of an interconnected power grid without disaster.
(If a country consumes 10000MWh in a year, they better not get above 2000MWh from wind+solar)
I can see a grid alternate between 22% -> 55% renewable energy one day, then 26% -> 48% the next day and ponder what that will look like when even more wind and solar get added.
Negative prices, exploding prices, the demand and supply of electricity have to match at all times.

The UK averaged about 34% wind and solar over the past year (mostly offshore wind), without the lights going out. While we do have some interconnectors to European power grids, they can only handle a small percentage of the UK's total demand. In the last year imports accounted for about 2%, while exports accounted for 4%, so not really a major reliance in either direction.

Fossil fuels were at about 43%, almost exclusively natural gas. This has been a concern due to a combination of the effects on gas prices from Russia's war, and an incompetent government failing to set up and fill adequate gas storage facilities in this country. With nuclear accounting for a fairly stable percentage across the year, the traces for gas and wind/solar are mostly mirror images of each other. It is a serious mistake not to have enough stored gas to cover a lengthy period of low wind.

In terms of variability there can be some relatively long periods of low wind generation. We had a run of about 30 days from late November to just before Christmas where it was cold, clear and still across most of the country, and you can see the resulting notch in renewable generation (down to about 19%), and corresponding spike in gas use on the graph. Solar is a fairly minor component of the UK power grid, and variation mostly comes down to the point in the year. Even with continuous clear weather, like we had, the solar generation in winter is very low due to how short the days are this far north (about 8 hours at the shortest, vs. 16 in the middle of summer). In summer solar can get up to about 8% exploiting the the long days.
 
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