Comment by idiotsecant | Hacker News Reader

Comment by idiotsecant | Hacker News Reader

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the economics of clean energy (as they are mostly presented in media) only work when there is sufficient dispatchable (typically dirty) power available. After a certain tipping point the grid is no longer stable if you provide only non-dispatchable generation on a MW-for-MW basis. In order to avoid this catastrophe you need one of two things - you need a multiplier on your clean power generation and investments in transmission to support it, or you need storage sufficient to make a non-dispatchable source dispatchable (and of course transmission to support that, but not quite so much). Otherwise, the physics simply don't work. The trend does not extrapolate. It all breaks!

Renewable energy is absolutely essential, but the path we are going down of simply building new renewable generation, performing a linear regression on that line, and assuming that it can keep going until the grid is 100% renewable is a big flashing red warning light to anyone who understands the physics. If you want to support renewable generation, support storage!!! Build batteries, build pumped storage hydro, build transmission. The generation is the easy part!

Without planning and policy, the economics of the issue will not solve it on their own, we will end up with a mess of an unreliable power grid until such time that the incentives no longer support building new renewables and we will have the worst of both worlds.

The cost of firm renewables is approaching a point where they are cheaper than fossil fuels. Firm renewables are dispatchabale because they're battery backed. Refer to the NextEra slide graphic in my comment below [1]. Maybe you need some natural gas or transmission in there to meet extreme shortfalls, but this is baked into the costs.

There's roughly 430GW of storage currently in US ISO interconnect queues wrt to your comment about supporting storage [2]. If the grid is unreliable, funds will be spent on storage to make it reliable, because the alternatives are uneconomical (Hawaii's Oahu island is replacing its last coal fired plant in the next 60 days with Tesla Megapacks for grid services, for example [3]). The demand for this is fairly evident [4].

[1] https://news.ycombinator.com/item?id=31926560

[2] https://www.energy-storage.news/estimated-427gw-of-energy-st...

[3] https://electrek.co/2022/06/27/tesla-megapacks-replace-hawai...

[4] https://www.teslarati.com/tesla-megapack-demand/

The NextEra graphic says "near-firm", not "firm". Some dispatchable generation is absolutely required.

The estimate is for late 2020s costs, which is not too far away. I'm guessing they ignored the end of the solar subsidy, and all the necessary grid changes to reach 100% renewables.

The O'ahu batteries replace the last coal plant, but not the last fossil fuel plant. Also, it's meant for black-start.

Nobody knows exactly what the last mile will look like yet. The graphic doesn't claim to know either. As a reader, you should not extrapolate those near-term forecasts and anecdotes all the way to the end.

Agreed no one knows what the last mile looks like, but all data demonstrates fossil fuels have very little role in that last mile. Your splitting hairs while the data is a bazooka of good news (with regards to cost decline and tech/manufacturing learning curves).

I didn't think I was splitting hairs. The data does not suggest what you say because the foundational assumptions stop being true the closer we get to the finish line. That's why you can't extrapolate the current trend all the way. It will take a different path.

Storage is something that until a few years ago I hadn't considered but it really is a big deal. I've talked to a number of people who say something like "If we run out of oil or really need to make changes we can just build more solar/wind/etc" but that only solves one side of the problem. You can't pour solar into a 747 (yes, I'm aware of the electric planes but they aren't passenger planes and aren't close to being that yet). Gas, for all it's problems, is incredibly energy-dense and replacing that is not something done easily.

There are some applications that need to be chemically powered for the foreseeable future, even with expected battery improvement. Those applications are also rounding error in the overall consumption of energy. I am happy with a world that is able to move away from coal, natural gas, and fuel oil burning to produce bulk electricity, even if that world still has 747s in it! One piece at a time.

No argument here, though while it may be a rounding error in overall energy (something I don’t know) the main uses I’m thinking of, planes and cargo ships, are pretty bad polluters which is a concern. And while pollution is my top concern, running out (or more realistically supply dropping and price skyrocketing) is a close second.

As in, I agree that all of this is a win but we could be forced into a very bad position if oil suddenly skyrockets in price due to scarcity (with no end in sight) and don’t have alternative, applicable energy storage options for things we depend on.

There is plenty of oil. Oil products are likely to increase in price due to lack of refinery investment.

We're already building millions of Electric Vehicles with giant battery packs. We need vehicle-2-grid, and the manufacturer, regulator, and grid operator alignment to support that.

Millions of EVs charging at night and the in the middle of the day, and discharging in the morning and evening, goes a long way to balancing demand and generates a tidy profit for EV buyers, further encouraging adoption.

Electric vehicle batteries are very, very far from sufficient. We cannot build enough of them. And, of much greater moment, we could not charge them up without a hell of a lot more renewable generating capacity than is planned.

We will need, after enough generating capacity is built out, much cheaper storage than any car has. Cars have radically different requirements for their storage than the grid does: fast charging, fast discharging, lightweight, compact, collision tolerant. These make it much more expensive than alternatives.

The utility storage that will be built will necessarily be much cheaper, and store enormously more, than even a fully electric fleet could store. We are nowhere near a fully electric fleet, and barely moving toward one. The exact mix of utility storage we will have is impossible to predict, but it will be driven by the cost at the time it is being built.

We need to build factories for every kind of storage now, even though some will not be favored later. Demand will be high enough that more expensive ones that have factories ready will find buyers even if another will be cheaper "soon".

It also goes a long way to decreasing the life of those battery cells. Will you voluntarily sacrifice a few years off your vehicles life for the health of the grid for a few pennies? Will your neighbor? Counting on EV storage is wishful thinking, we need dedicated storage.

Base Model 3: 57.5 kWh battery.

In California, charging at 40c/kWh during the day and discharging at 85c/kWh (for evening peak) would yield about $23 daily - or $8,400 annually.

Most Tesla's retain above 90% battery capacity after 100,000 miles [1]

Completely charging and discharging daily for one year is equivalent to 99,280 miles. A new Model 3 battery pack costs $15,800 [1] currently. 10% degradation is equivalent to $1,580.

Doing this currently would provide a ~7-year payback period on a Model 3.

[1] https://evannex.com/blogs/news/tesla-model-3-battery-degrada...

[2] https://www.slashgear.com/857917/replacing-the-battery-pack-...

On one hand you suggest that we can solve grid battery storage if everyone contributes their personal vehicle battery packs, then on the other hand you suggest prices to support that based on current time of use billings curves. You of course realize that if everyone was contributing power during these times the amount you'd earn from it would be a tiny fraction of what it is now. On top of that, you're assuming a very, very high premium for the power you're selling anyhow. PG&E in California does offer time of use net metering at a much lower rate, but it's not going to be the prime CAISO rate for obvious reasons.

I ask again - would you do that? Do you think your neighbors would do that? Do you think it's reasonable to base an entire power grid on that? What about if power starts to get cheaper on a particular day? Do you let the grid reach brownout status based on individual market pricing of individual actors?

Or do you just build some dedicated storage stations like any reasonably designed system?

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