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by dvasdekis 1428 days ago
The surprising inference from me, as an energy layman, is that solar output coincides with periods of peak demand. Obviously this is seasonally adjusted, but in an era when the Saudis have solar contracts being supplied for $10USD/MWh [0], the potential profits for a solar provider at periods of peak demand seem more than sufficient to encourage investment, especially with interest rates still at a historic low for big capital projects.

So, what gives? Where's the solar?

[0] https://reneweconomy.com.au/saudi-solar-plant-locks-in-new-r...

5 comments

Solar capacity in Texas tripled since last summer.

https://www.washingtonpost.com/opinions/2022/07/21/heat-ener...

Another factor for building solar right this moment is that the price of polysilicon has jumped to the point where large projects are potentially at risk of cost overruns/delays. Growing pains.

https://www.bloomberg.com/news/articles/2022-07-22/china-is-...

What does it take to setup a decent size solar farm? There’s a lot of cheap, flat, easy to develop land in far west Texas (Brewster county).
The hardest part tends to be the interconnection to the grid, at least in most of the country. I think that ERCOT is also experiencing geographic regions with consistent grid congestion, though I can't recall which. That data is all public, but there are some providers that make it nice and easy to view:

https://www.energyacuity.com/blog/ercot-lmp-map/

Grid connection, land use permissions (i.e. local planning). The latter is very easy in rural Texas so just the former really.
Don't forget about environmental studies and approval.
That's a big problem in most of the US, especially the Coasts. Not so much in Texas.
In Texas?? Lol
One thing I wonder about is how far can you be from population centers in practice? I remember hearing that you want to be close or else you lose a lot to transmission but that might not be at all true
Long distance synchronous AC transmission or HVDC transmission is pretty efficient - enough to overcome the inherent land pricing differential.
You make the X vs Y call.

Assuming it is material, at some distance the cost of land (X) vs the transmission loss (Y), it becomes economical to choose X instead of Y

It doesn't take much honestly: https://www.erthos.com/
Thanks! Makes sense if it's being built as fast as possible given the number of workers available for installation.
Solar is actually super super hard to install right now, because tariffs are in an uncertain space, so nobody knows if, should they import, if they are are going to get a bill in the next 12 months for past sales that's 1x-2x the cost of the import (I forget the exact factor).

This sort of protectionism isn't even buying us a bunch of local solar panel production, unfortunately. I'm not a free-market purist, and am in favor of protectionist tariffs to build a nascent industry, but this is not a way to do to it and we are only harming our installer industry with these terrible forms of tariffs and uncertainty.

Edit: here's an article from a little while ago on this

https://www.reuters.com/world/us/us-solar-industry-warns-slo...

There’s about 100GW of solar generation in ERCOT’s interconnect queue at the moment. If there is uncertainty, utility scale developers aren’t signaling it.

https://news.ycombinator.com/item?id=32071998

> As of 30 September [2021] developers had 100.3GW of solar capacity in the queue, 42.4GW of utility-scale battery storage, 22.5GW of wind, 13.5GW of natural gas and minor amounts of other technologies such as biomass.

For comparison, ERCOT has a maximum capacity of 15GW of coal generation, and 65GW of fossil gas generation (per electricitymap.org, which sources zone capacity data in the US from US EIA-860 reporting).

Well if you are a solar developer it makes sense to get in line in the interconnection queue and hope that this stupid tariff stuff gets sorted out before it's time to actually buy all the panels. But I bet we'd have a lot more installed all over the US if it weren't for this.
> But I bet we'd have a lot more installed all over the US if it weren't for this.

Agreed. Solar PV module tariffs are suspended for 24 months FYI, so there is some near term policy clarity for utility scale developers. The ITC tax credit is also phasing down over the next 2 years, so the incentive is there to build build build.

https://www.utilitydive.com/news/biden-to-pause-solar-tariff...

https://www.whitehouse.gov/briefing-room/statements-releases...

Since batteries are always the issue... How inefficient is mechanical storage? For example using electricity to just raise a heavy mass then as that lowers it can produce power. It seems that would be cheap to build at scale with the chance for almost unlimited storage.

I have to assume there would be a more than 50% loss through the process, hope someone on hn can comment. Maybe it's not worth it when you can tap into unlimited sunlight the next day.

> How inefficient is mechanical storage?

The density is the problem.

If you raise a 25,000kg mass by 100m, that's 24.5MJ, or roughly the energy contained in one kilogram of coal. Or 6.6kWh (standard meter units) of electricity.

(and that's on the input side, not accounting for losses)

This system is currently only cost-effective with water, and only where you have a natural place to put it (i.e. a crater on top of a mountain vs. building a tank on a tower). Constructing a greenfield mechanical apparatus is too expensive for the energy stored.
Pumped hydro is usually considered the best way to do this. Basically, you pump water from the bottom of the dam back up to the top. This is great because you probably already wanted most of the infrastructure for hydroelectric power; the pumps are a relatively inexpensive addition once you have that. There are other techniques, but pumped hydro is generally what you'll see for this reason.

Flywheels are also pretty good short term, but supercapacitors mostly do their job better these days. That said they are competitive, and technological changes could nudge them into more use. Just making your wind turbine really large gives a flywheel effect, e.g., so again if you already have a spinning thing they are often worth it.

Not worth it, easier to scale up battery manufacturing (which the world also needs for all vehicles to transition to electrification).

https://youtu.be/iGGOjD_OtAM

People are actively researching and working on kinetic energy storage systems, for example https://www.energyvault.com/ev1
> 100GW of solar generation in ERCOT’s interconnect queue at the moment.

This seems mad - is that built and not connected, or just awaiting permitting?

Interconnection listing is one of the first stages for a project; but that doesn't mean that all of these projects will go through.

It does give a good sense of investor sentiment between relative technologies, however.

That’s surely the purpose. Natural gas and coal interests want chaos and uncertainty in solar coated with a glaze of misdirection.
> So, what gives? Where's the solar?

Being installed as fast as the fabs can churn it out? Production capacity isn't infinitely elastic, factories take time to build. Solar is growing very rapidly, for reasons exactly like this, but it's not magic.

Also huge tariffs on Asian solar panels cuts demand.
Tariffs are a thing, but there is absolutely no shortage of demand right now, and hasn't been for a while.
It's a bit more insidious than that, because uncertainty on the part of the importer means that they don't know how much to charge. A tariff action in the future can be assessed on past sales, and when you don't know how much can be assessed, you can't even really hedge or buy and then give rebates later. It's a really fucked up situation.
That may be so, but it remains the case that every wafer that comes out of a solar panel fab gets sold, with a large backlog of demand in every market. And the supply side is responding to that by building out capacity rapidly. Tariffs may or may not be "fucked up" as a matter of principle, but in practice they aren't a barrier.
They get sold, just not in the US, or specifically, Texas, as the original poster was asking.

This hurts us in the US, quite a bit. And I wouldn't mind, if it meant that there was going to be a more robust US industry for panel production, as that would be fantastic. But the tariffs don't appear to be designed for that, but instead to benefit a few tiny manufacturers that are not expanding.

Is every wafer that comes out of Asia being purchased in the USA or have tariffs shifted demand to other countries? How have tariffs affected future purchase orders and new factory build outs? I’m just having a hard time believing they have a negligible effect when the worlds second largest economy adds added cost to solar panel imports.
What makes you say there is no shortage of demand? If demand is elastic then lower price would mean more demand. I know that’s just econ101 which is often misleading, but what makes you say otherwise?
I only ever took econ 101, so forgive me if I'm missing a subtle point...

Isn't saying that there exists a *shortage* of demand the same as saying that there is available supply but no one is willing to buy at the current price? Thus, by definition, there cannot be a shortage of demand if all units are being purchased at the current price?

On a typical supply and demand curve you can expect that raising the price reduces demand. No one in this thread has actually established that all units are being purchased by the USA. So what you will see are projects in the US that would have gone to solar if it was 30% cheaper but instead go to natural gas or some other source, and those units that would have been purchased get purchased by people in other countries.

But also if demand significantly exceeds supply, that is cause for manufacturers to make more investment in increased production. You’d see major solar projects booking out orders six months in advance for example, and with more demand they would book out one year in advance let’s say. So the thing is that demand is a gradient and it’s not a binary thing of “everything is being purchased”. Raising the price of something will usually price someone out of that purchase.

I found this really interesting as well as here in New Zealand that relationship is inverted - we don't typically have residential air conditioning yet use a lot of electric heating so our peak demand is in the mornings and evenings, and most intense in the winter. This makes the business case for solar a lot trickier here as the periods of max generation (daytime during the summer) coincides with low demand and subsequently low wholesale energy prices.
It makes we wonder if something like the Australia-Asia power link would make sense. 2.2GW would be enough to cover current Gas, Coal and Diesel generation for NZ. With sufficient storage (Batteries, Pumped Hydro), you could recharge in the day, carry load into the evening peak, before switching to stored power.

Initial cost would be higher, but long term cost of Solar is ridiculously cheap.

> It makes we wonder if something like the Australia-Asia power link would make sense.

There is the AAPowerLink project which proposes exactly this. It's a ~20GW solar farm in Australia with battery storage and a 4500km HVDC undersea cable to export power to Singapore. Seems currently in a planning and Project seems to be in a planning and exploration stage with funding not fully secured though.

Doesn't New Zealand have tons of hydro? Is it possible summer solar could be used to pump up a mountain reservoir somewhere with that energy sold 6 months later at a premium?
Getting only one cycle per year out of your storage solution is hard to justify economically. Regular pumped hydro gets 200-365 cycles per year, and there's already a substantial difference between day and night electricity prices.
I've seen this idea elsewhere, but for latitudes like NZ it makes sense to tilt panels in a way that it optimises for winter & morning/evening sun.

Also wonder how much kWh batteries one would need for winter heating (generate at day, use at evening). Kinda feel NZ, especially north island should have enough. Over in Eastern Europe you can get recycled batteries for $150/kWh!

Wind should work better than. Especially offshore. Tends to be much more expensive than solar in a sunny place like Texas, but also much more reliable/stable.

In the end, you'll always need a mix of supply. Or simply better insulation and efficient heat pumps rather than wasting electricity on heating at above freezing.

People need to realise that not all forms of renewable generation are good solutions in all parts of the world, just because they're renewable. I hate the "green energy" cults that shout you down for suggesting solar might be bad idea for these sorts of reasons.
Well, bad idea for now. If we can start storing up solar energy for the winter, then it might start making a lot of sense. The sand battery that can store thermal energy for months seems pretty interesting in this aspect.

https://www.bbc.com/news/science-environment-61996520

Getting one discharge per year and being less than 30% efficient is a major limitation for any kind of construed thermal battery.

A more viable though still impractical approach is to store energy in rocks underground. Essentially trading the need for a multi km deep borehole for geothermal with the need to provide your own heat.

The first thing I did was move the mouse over the demand curve and noticed that it was 1:1 with something in the wind / solar box. It is almost too obvious that there should be 20-30GW of solar installed.

So much for "sometimes the wind doesnt blow" as well. Looks like they are doing just fine with their wind power in texas.

This is why some places have net metering arrangements for PV. Energy provided at your yearly and daily peak and located at your demand centers and so reducing peak transmission load? Worth far more than the 1 for 1 offer adopted purely for convenience due to how old meters worked.

Yet Texas doesn't have such a policy statewide. Because a simple money saving idea got politicised and lots of people got convinced they were subsidizing liberal elites, rather than paying their neighbours for providing a useful service.