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Solar’s Future is Insanely Cheap

rameznaam.com

171–180 of 223 posts

Re: Solar’s Future is Insanely Cheap

#171

Earlier quoted context omitted.

If my understanding is correct there is curious difference in perceived scale with kinetic vs thermal energy. Based on a a rowing machine's advertised metrics, I calculated you could row across the English channel on half a packet of chocolate biscuits.

This sounds interesting but I don't really understand, could you elaborate?

1 biscuit = 85 cal

1000m rowing = 60 cal [1]

English Channel = 35km (narrowest point)

35 * 60 / 85 = 24.7 biscuits!

[1] https://darkhorserowing.com/how-to-translate-calories-to-met...

Re: Solar’s Future is Insanely Cheap

#172

Earlier quoted context omitted.

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.

I don't know about its efficacy, but my favorite means of mass energy storage is a gravity battery: literally stacking heavy blocks in a huge tower, which are raised and lowered based on energy demands by automated cranes. https://en.wikipedia.org/wiki/Energy_Vault

There are many nifty schemes like this, such as compressed air, cryogenics, hydrogen, thermal, different battery chemistries, etc. Efficacy in the form economic scalability is the crucial characteristic.

Re: Solar’s Future is Insanely Cheap

#173

Earlier quoted context omitted.

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.

I don't know about its efficacy, but my favorite means of mass energy storage is a gravity battery: literally stacking heavy blocks in a huge tower, which are raised and lowered based on energy demands by automated cranes. https://en.wikipedia.org/wiki/Energy_Vault

Seems like a novel take on the same principal behind pumped storage hydro systems. But, at a max of 80MWh of storage, you'd need hundreds of them to match a single pumped hydro facility, which often have 10,000+ MWh of storage.

Re: Solar’s Future is Insanely Cheap

#174

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…

> The fact of the matter is that an intermittent kWh is not as valuable as an on-demand reliable kWh

Don't worry -- every single time renewables are mentioned on HN, this aspect is at the top of the posting.

Re: Solar’s Future is Insanely Cheap

#175

Earlier quoted context omitted.

It's not a bullshit purity test at all. It highlights the extremely neglected costs in raw material and non-electrifiable infrastructure that is required to produce materials that are nominally 'green'. In some cases it's questionable if some green technologies actually are a net positive at all. There is a strong 'abundance' bias implicit in articles by people like Ramez Naam, who push so strongly for green energy p…

> It highlights the extremely neglected costs in raw material and non-electrifiable infrastructure that is required to produce materials that are nominally 'green'. Ignored by whom? You? In fact, embedded energy is a huge consideration in the evaluation of green technologies.

It’s a depressingly common reality that “nobody has considered” is effectively equivalent to “I haven’t considered” on the internet.

The idea that solar panels might not be more efficient than burning coal is not an opinion held by someone who has done any level of research on the subject at all.

Re: Solar’s Future is Insanely Cheap

#176

Earlier quoted context omitted.

Or just smarter appliances. Plenty of opportunities for thermal banking/battery banking. Most of my loads, on average, don't need to run that exact second . I don't mind if my hot water tank super-heats water in the middle of the day for the rest of the day. If electricity is really cheap, my freezer can jump into overdrive. I don't need my clothes to dry in the next hour, just over the next 8. I don't care if my fri…

>I don't mind if my hot water tank super-heats water in the middle of the day for the rest of the day. Water does not have the capability to store much energy. >If electricity is really cheap, my freezer can jump into overdrive. Your freezer can't if it's not a ammonia refrigerant. You will actually be wasting energy. >I don't care if my fridge/freezer takes a break Your fridge actually does not use electricity const…

> Water does not have the capability to store much energy.

Systems that make ice at night and use it for A/C during the day date back to the 1950s.

The general class of these facilities is phase-change materials. Water is pretty amazing, both for ice and for steam.

Re: Solar’s Future is Insanely Cheap

#177

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.be/Zk11vI-7czE

Re: Solar’s Future is Insanely Cheap

#178
post #71

Earlier quoted context omitted.

Intermittency and the unsuitability of grid storage batteries to compensate is heavily played up by the carbon industry. The future of low emissions energy production will be largely driven by overproduction and demand shifting, not banks of grid level batteries. This likely won't happen as soon in America, however, the economy is too tied in to fossil fuels and the appetite to upgrade the electric grid by utility co…

But the solution isn't batteries, it stored hydroelectric. Only works where you have mountains though.

How is that a solution when it's difficult to build more of it?

Re: Solar’s Future is Insanely Cheap

#179

Earlier quoted context omitted.

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.

I don't know about its efficacy, but my favorite means of mass energy storage is a gravity battery: literally stacking heavy blocks in a huge tower, which are raised and lowered based on energy demands by automated cranes. https://en.wikipedia.org/wiki/Energy_Vault

Hmm I'm not so sure about that: gravity is weak.

In some news article they say Energy Vault uses 35-ton blocks hoisted up to ~150 m - while it sounds impressive, that's only 14.3kWh (assuming 100% conversion efficiency), or about 1/7 of a single Tesla Model S (100kWh).

Re: Solar’s Future is Insanely Cheap

#180
post #44

This tells me that until fossil plants are mostly shut down (and perhaps afterward), we will continue to have negative electricity prices at times. It might be a profitable idea to buy extra energy storage capacity to get paid for storing energy at certain times, then sell it when it is high demand.

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.

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