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Solar’s Future is Insanely Cheap

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Re: Solar’s Future is Insanely Cheap

#201

Post by pfdietz »

opo wrote: post #137
remmargorp64 wrote: post #73

Earlier quoted context omitted.

All they need to do is build mechanical/hydraulic systems for storing solar power during the day and unleashing it at night. For example, use solar power during the day to pump fluid from a lower reservoir into a higher reservoir, and then harness the energy of the water flowing from the higher reservoir into the lower reservoir through turbines. As long as your output energy is always coming from the turbines, and a…

>...For example, use solar power during the day to pump fluid from a lower reservoir into a higher reservoir, and then harness the energy of the water flowing from the higher reservoir into the lower reservoir through turbines. Trying to rely only on intermittent power sources has huge storage requirements due to weather along with daily/seasonal variation. If grid energy storage was a simple problem it would have be…

> If grid energy storage was a simple problem it would have been done decades ago.

Except storage is much less useful in the old paradigm, so the motivation wasn't there. Going forward, prices will swing wildly, so storage will be more valuable.

Re: Solar’s Future is Insanely Cheap

#202

Post by pfdietz »

m463 wrote: post #177
sephamorr wrote: post #28

Power markets are more complicated than most people realize. One thing to note is that solar power can be cheaper than gas, but still not be economic. The fact of the matter is that an intermittent kWh is not as valuable as an on-demand reliable kWh to a utility who's number 1 priority is reliability. Even as solar is acquired at lower and lower prices, if evening power is generated by expensive and inefficient gas t…

also, solar might not be solar. "Utility scale solar" is ambiguous and can mean solar thermal or pv solar. I think solar thermal might be a completely different animal that is not long-lived and not clean. It might be a similar situation to where "renewable power" turns out to me mostly burning garbage or burning trees. This documentary might be a little biased but also have some interesting insights: https://youtu.b…

Concentrated solar thermal is basically dead. PV just slaughtered it.

Re: Solar’s Future is Insanely Cheap

#203

Post by 2wrist »

gwright wrote: post #139
blake1 wrote: post #81

Earlier quoted context omitted.

As mentioned in the article, solar power is insanely cheap. So while you are right that a kWh of solar is not, on average, as valuable as a kWh of semidispatchable coal, the insane cheapness means that at some point, it is economical to massively overbuild renewable and decommission fossil fuel plants. You provide no evidence for the implausible claim that solar causes emissions to go up: your argument is only that t…

It doesn't matter that if solar/wind is cheap (or even zero) because you still have to have an alternate power source for when your intermittent power has gone AWOL. You need cheap grid-scale storage, which doesn't exist at the moment.

Hydrogen... which can then be put back through a fuel cell to produce electrickery. The germans are looking at this. I believe.

Re: Solar’s Future is Insanely Cheap

#204

Post by EarthMephit »

sephamorr wrote: post #28

Power markets are more complicated than most people realize. One thing to note is that solar power can be cheaper than gas, but still not be economic. The fact of the matter is that an intermittent kWh is not as valuable as an on-demand reliable kWh to a utility who's number 1 priority is reliability. Even as solar is acquired at lower and lower prices, if evening power is generated by expensive and inefficient gas t…

Battery prices are also dropping, although as not as fast as solar, but its at the point where in some regions solar + battery is cheaper than coal

Modern Gas turbines can also act as a good backup for solar in times where there is unusual demand because they can start up on under a minute

Re: Solar’s Future is Insanely Cheap

#205

Post by SAI_Peregrinus »

Retric wrote: post #99
rootusrootus wrote: post #52

Earlier quoted context omitted.

Here's a recent analysis: https://teslatap.com/articles/solar-vehicle-roof-analysis/ To me it looks like it will never be a meaningful solution, due simply to physics.

That has several really bad assumptions by assuming all solar roofs need to fit on an existing Tesla‘a roof. > The usable clear area of a Model S glass roof is 42” x 45” A Model S is actually 195.9” by 77.3 (ex. mirrors). Assuming a reasonable shaped solar car using 75% of that surface is covered in panels that’s 12x the area. But you also gain from panels covering the sides of the vehicle. Further “Because the vehic…

> Solar panels and batteries are both DC so you don’t need an inverter, the charge discharge efficiency of lithium ion can be over 90%.

You'll still need a DC-DC converter, which is just an inverter with a rectification step. The 81% number is low, but there is a loss here.

Re: Solar’s Future is Insanely Cheap

#206

Post by [deleted] »

SAI_Peregrinus wrote: post #205
Retric wrote: post #99

Earlier quoted context omitted.

That has several really bad assumptions by assuming all solar roofs need to fit on an existing Tesla‘a roof. > The usable clear area of a Model S glass roof is 42” x 45” A Model S is actually 195.9” by 77.3 (ex. mirrors). Assuming a reasonable shaped solar car using 75% of that surface is covered in panels that’s 12x the area. But you also gain from panels covering the sides of the vehicle. Further “Because the vehic…

> Solar panels and batteries are both DC so you don’t need an inverter, the charge discharge efficiency of lithium ion can be over 90%. You'll still need a DC-DC converter, which is just an inverter with a rectification step. The 81% number is low, but there is a loss here.

[deleted]

Re: Solar’s Future is Insanely Cheap

#207

Post by Scoundreller »

greglindahl wrote: post #180
Scoundreller wrote: post #63

Earlier quoted context omitted.

I just wish the negative electricity prices reached the non-industrial consumer. If it reached me, I'll have an Arduino controlled hot water heater, furnace and fridge/freezer dynamically turning on/off to take the most advantage of prices pronto.

It's all up to the charging algorithm. If your grid access is priced according to energy transferred, you pay a positive retail price no matter how negative the wholesale price is. If your grid access is a fixed charge, you could directly take advantage of the negative wholesale price. In some places, industrial users have the second algorithm.

Reality is that grid access (transport/distro) should be more variable too.

Line sag is worst when demand is highest or it’s hot outside. Same with running out of transformer capacity.

When an upgrade is triggered, it’s to build more peak capacity.

Re: Solar’s Future is Insanely Cheap

#208

Post by mistermann »

pfdietz wrote: post #170
mistermann wrote: post #131

Earlier quoted context omitted.

> I suspect you are just repeating anti-renewable lies here. You speak with a tone of authority - do you have deep expertise and knowledge in this field? Yes or no? Please don't dodge the question. This is the best article I could find with about 10 minutes of googling. I have excerpted a small portion, but there is more relevant information immediately following this portion. This does not sound like a solved proble…

The listing of cadmium there should be a tipoff. Cd is used in CdTe, which is a small and shinking fraction of the PV market (most is Si, which does not use Cd; CdTe is also limited by the availability of tellurium). And I already explained about lead. The projection there that c-Si market share will shrink seems very dubious. c-Si market share is growing, not shrinking (displacing multi xtal Si). The waste from PV i…

Perhaps you should become a consultant, sounds like you can save these countries a lot of money by telling them how things really are.

Re: Solar’s Future is Insanely Cheap

#209

Post by mistermann »

avmich wrote: post #194
mistermann wrote: post #107

Earlier quoted context omitted.

> Of course it is considered... One would certainly hope so, but lots of weird things happen on this planet. Where could someone who is interested to learn about the degree to which this is true go to read about what is really happening on the ground? Where did you learn about it?

First, Fermi estimate. You can estimate how much something weights, costs, takes to construct etc. Then you become particularly good in it when you read texts from this area, so you gradually replace your estimates with data. And correct your errors when they disrespect reality too much. It's harder to estimate CO2 emissions from cement production from first principles; but you may have actual numbers from typical pl…

Sorry, I'm not doubting that it can be done, I'm wondering about how you know it is done. Huge difference.

Re: Solar’s Future is Insanely Cheap

#210

Post by woodandsteel »

mistermann wrote: post #108
woodandsteel wrote: post #102

Earlier quoted context omitted.

Vaclav Smil is looking at this all wrong. There are three phases here 1) power is produced by plants that take fossil fuels to build and fossil fuels to run 2) power is produce by plants that take fossil fuels to build and no fossil fuels to run 3) power is produced by plants that were built using renewable energy and run off of it too. Most of the people who focus on phase 2 basically want us to stay on fossil fuels…

> Most of the people who focus on phase 2 basically want us to stay on fossil fuels forever, but they don't want to come out and say it. How do you know this? Serious question.

Because if you leave out the first and third phases, then there is no reason to develop renewables and get off of fossil fuels. And if that was not what they thought, they should say it, but they don't.

But let me ask you the question, what is your position on global climate change and renewables? Do you believe global climate change is real, caused at least considerably by human fossil fuel emissions and dangerous? Do you believe we should be replacing fossil fuels with renewables?

And what do you think of my three phase analysis?

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