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A near 100% renewables grid is well within reach, and with little storage

reneweconomy.com.au

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Re: A near 100% renewables grid is well within reach, and with little storage

#131

Post by throwaway894345 »

Retric wrote: post #115
ZeroGravitas wrote: post #105

Earlier quoted context omitted.

Yeah, but that renewable hydro is unlikely to grow much in the USA, while wind and solar will be growing exponentially. Hydro is cool, and works well with solar/wind/nuclear to help match supply and demand, but ... If you look at global renewable output, the big chunk of hydro production that's been flat for decades, somewhat obscures the recent sudden rise of solar and wind.

Swapping hydro from 24/7 power to a backup for wind and solar goes a long way to eliminate the need for storage. We don’t need more total kWh per year of hydro we need to be able to more flexibility get those kWh.

I’m not sure that’s true. Electricity generation is pretty regional, so it’s not like we can use a region’s hydro capacity to store energy for other regions. It can store energy for the region that already has hydro, but that region already has hydro so it probably needs less storage in the first place?

Re: A near 100% renewables grid is well within reach, and with little storage

#132

Post by ZeroGravitas »

eldaisfish wrote: post #117
ZeroGravitas wrote: post #99

Earlier quoted context omitted.

No, because there never is such an issue. Renewables can turn themselves off and on so fast that this won't ever be a problem. The current Australian model we're discussing has about 15% 'overgeneration' because that's economically efficient, there's no problems caused by that.

What you have in mind requires someone to do the coordination. that is currently the system operator and they operate at a data rate measured in minutes or 4 s for the fastest changes (e.g. PJM). Meanwhile, solar output can go from 100% to 10% in three seconds. How is this not a problem?

The problem anonporridge was talking about was the 10% of solar meeting the current demand and then suddenly going to 100% in three seconds, so there's 'too much' power on the grid i.e. overprovision breaking things. Which it doesn't.

While your example is solar at 100% exactly meeting demand, and then dropping to 10% in 3 seconds, and the fix for that is: overprovision (and some other stuff).

They do need to have decent predictions of demand and supply, like this graph that shows the 1-hour ahead and 24-hour ahead predictions:

https://www.caiso.com/TodaysOutlook/Pages/default.aspx

To get the whole grid working together, but we already have that, and renewables and batteries help in various ways.

Re: A near 100% renewables grid is well within reach, and with little storage

#133

Post by Schroedingersat »

insane_dreamer wrote: post #118
Schroedingersat wrote: post #103

Earlier quoted context omitted.

For the cost of 5kW nameplate of new western nuclear (>$10/W) you can get, right now, at retail, as an individual: 50kW nameplate of solar, and 8kW nameplate of wind, and 75kWh of storage and a 5kW generator (which will almost never need turning on) and a biogas digester. And it will produce enough excess power to replace itself (with a cheaper version) or just triple the batteries if you can get 2-3c/kWh for the sur…

nuclear definitely needs to be in the mix to reach 100% fossil-fuel-free energy generation; not gonna happen on wind/solar/hydro alone

You're literally commenting on a thread about how 100% renewable is possible on a comment demonstrating that an individual can beat the cost effectiveness of new nuclear with 100% renewables.

The utility scale version of the digester is a gas peaker running on green ammonia possibly with a mix of long distance transmission. Everything else scales at least linearly.

Nuclear is dead. The last nail went into the coffin when green hydrogen first hit parity with delivered grey hydrogen in some regions. The case just gets worse from here. Stop shilling.

Re: A near 100% renewables grid is well within reach, and with little storage

#134

Post by philipkglass »

eldaisfish wrote: post #117
ZeroGravitas wrote: post #99

Earlier quoted context omitted.

No, because there never is such an issue. Renewables can turn themselves off and on so fast that this won't ever be a problem. The current Australian model we're discussing has about 15% 'overgeneration' because that's economically efficient, there's no problems caused by that.

What you have in mind requires someone to do the coordination. that is currently the system operator and they operate at a data rate measured in minutes or 4 s for the fastest changes (e.g. PJM). Meanwhile, solar output can go from 100% to 10% in three seconds. How is this not a problem?

PJM has "Regulation D" signals for sub-second response from energy storage resources (which are mostly batteries in practice):

https://www.pjm.com/~/media/committees-groups/task-forces/rm...

An energy storage regulating resource, such as a battery or flywheel, cannot burn fuels to produce electricity, but instead charge and discharge energy from the bulk electric system itself through a power inverter. Energy storage devices can match a desired output within 200 milliseconds of receiving the regulating signal; therefore these resources do not need to model any dynamics, ramp limitations, or dead-bands.

Australia is also using batteries in a similar way:

"South Australian Battery Responded in Just 140 Milliseconds After A Coal-Fired Power Plant Failed"

https://www.sciencealert.com/elon-musk-s-south-australian-ba...

Re: A near 100% renewables grid is well within reach, and with little storage

#135

Post by anonporridge »

eldaisfish wrote: post #117
ZeroGravitas wrote: post #99

Earlier quoted context omitted.

No, because there never is such an issue. Renewables can turn themselves off and on so fast that this won't ever be a problem. The current Australian model we're discussing has about 15% 'overgeneration' because that's economically efficient, there's no problems caused by that.

What you have in mind requires someone to do the coordination. that is currently the system operator and they operate at a data rate measured in minutes or 4 s for the fastest changes (e.g. PJM). Meanwhile, solar output can go from 100% to 10% in three seconds. How is this not a problem?

One thing I've learned recently is that grid management is extremely primitive. People are literally emailing each other word docs and pdfs and calling each other on the phone to make changes to generation output to keep the grid stable.

It's an area that's ripe for some software innovation, if they can actually break through the legacy management club that currently runs the grid.

Re: A near 100% renewables grid is well within reach, and with little storage

#136

Post by qqqwerty »

evancox100 wrote: post #110
Schroedingersat wrote: post #103

Earlier quoted context omitted.

For the cost of 5kW nameplate of new western nuclear (>$10/W) you can get, right now, at retail, as an individual: 50kW nameplate of solar, and 8kW nameplate of wind, and 75kWh of storage and a 5kW generator (which will almost never need turning on) and a biogas digester. And it will produce enough excess power to replace itself (with a cheaper version) or just triple the batteries if you can get 2-3c/kWh for the sur…

So you can buffer the wind/solar output for just 78 minutes? Doesn’t sound like a complete solution. Edit: I guess per the paper it really depends on the specific details of generation/load timing. Could be workable for a certain region but not for another.

The parent is pointing out, that if you are trying to find a solution to generate 5kw of constant power using nuclear, for the same cost you can get an absurd amount of renewable generation and storage plus a backup generator. The batteries can store 15 hours worth of energy at peak demand, you get a 10x overbuild of peak capacity in solar, plus wind, biogas and a backup generator to boot. It is highly unlikely that the system would ever fail. I would guess you could probably cut the system size in half and still have uptime in the high 9's. And the added bonus is you would have a fair bit of redundancy should any part of the system need maintenance, whereas the nuclear solution doesn't even come with a backup generator.

Re: A near 100% renewables grid is well within reach, and with little storage

#137

Post by ZeroGravitas »

anonporridge wrote: post #130
ZeroGravitas wrote: post #99

Earlier quoted context omitted.

No, because there never is such an issue. Renewables can turn themselves off and on so fast that this won't ever be a problem. The current Australian model we're discussing has about 15% 'overgeneration' because that's economically efficient, there's no problems caused by that.

It's not a technical issue, but an economic one. If you have so much wind and solar generation that they spend too much of their lifespans sitting idle and not generating income, they potentially never even pay for their initial build cost and basic maintenance, let alone be a better investment than just buying a treasury note yielding 1%. That's a recipe for long term stagnation and depression.

Well the economic part is solved by solar/wind/batteries being much cheaper than all the other options, that's why this model overprovisions wind and solar.

So yes, lots of solar might make it more cost effective to add some wind and/or batteries and vice versa but that's a good thing and what this model explores.

Re: A near 100% renewables grid is well within reach, and with little storage

#138

Post by throwaway894345 »

jaltekruse wrote: post #114
hammock wrote: post #82

Earlier quoted context omitted.

> even before the recent climate bill passed What is in the bill that is investment in renewables? My understanding is that there aren’t so much subsidies to generators-suppliers, but rather rebates and savings for homeowners and consumers.

Getting people to use more efficient appliances and insulating their homes should help reach these targets. We don't need to generate today levels of energy if we can drop usage by some percentage and just generate all of that with renewables. That being said, the bill is also pushing for heat pumps to replace natural gas burning furnaces, so I'm guessing the net impact will be we need today levels of electricity gen…

> Getting people to use more efficient appliances and insulating their homes should help reach these targets. We don't need to generate today levels of energy if we can drop usage by some percentage and just generate all of that with renewables.

Sure, but if the bulk of the problem isn’t residential inefficiency (or if these incentives are only going to recoup a small portion of that inefficiency), then perhaps this money and political will might be better spent elsewhere.

In particular, I suspect industry is a big emitter and the big gains are probably to be had in disincentivizing carbon emissions in industry. The low hanging fruit would be a border adjustment tariff on countries that don’t meet our current emission standards (bring more jobs to the US, which improves our supply chain security). From there we could set a low price on carbon and ratchet it up as necessary. I would much rather us squabble over the price of carbon than trying to play whack-a-mole with specific incentives and disincentives. Moreover, carbon pricing isn’t a cost, it’s a revenue source.

Besides carbon pricing, it would also be neat to see the money spent on increasing our renewable energy capacity. It’s not enough to convert our grid to renewables because we have all of these new EVs and electric heaters and electric industrial applications coming online and replacing fossil fuel applications. The grid is going to be much more strained than before, so we need to increase that capacity as quickly as possible.

Re: A near 100% renewables grid is well within reach, and with little storage

#139

Post by epistasis »

throwaway894345 wrote: post #127
ZeroGravitas wrote: post #69

Earlier quoted context omitted.

Quite a lot of people live in Texas and California where renewables are already pretty advanced, plus there's nuclear in the north, and they have hydro and grid connections with Canada who have even more hydro and nuclear so the USA should be easier. The US intends to hit this target (i.e. 95% carbon-free generation) in 8 years I think, with 100% and wider electrification of current fossil fuel uses in 2035 and it di…

The problem is that electrification of fossil fuel applications is going to significantly increase the demand on our grid. So it’s not enough to get to parity in renewables, but we have to go far beyond our current capacity in order to accommodate a world in which almost every car is electric (whether electric hybrid or green hydrogen) and almost every home uses electric rather than natural gas for heating (not to me…

It's going to increase the amount of energy flowing through the grid, but there's plenty of excess grid capacity to accommodate that.

The grid is a technological marvel, but one weakness about it is that it has never included storage except small amount of hydro (which I've heard some claim is because nuclear needed it so that the reactor could stay always on, but I have my doubts on that origin story)

Without storage, every grid component must be sized to maximum expected through put, which can be many many times as large as average throughput. The grid is also the most expensive part of delivering energy, more expensive than generation.

This means that storage, and a lot of electrification means storage, whether that's charging the battery on a car, or heating a hot water tank, or cooling/heating a building which can be used as several degrees of thermal storage, is going to drastically reduce the potential peak load as a ratio to average load.

Electrification has enormous potential to reduce grid cost, and overall energy cost, IMHO.

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