AukeHoekstra Profile picture
May 25 18 tweets 4 min read Read on X
California is entering phase 2 of something we will see worldwide:

Phase 1)
Solar+wind replace up to ~70% of fossil electricity

Phase 2)
Solar+wind+batteries replace up to ~90% of fossil electricity

Phase 3)
Solar+wind+batteries+eFuels replace 100% of fossil electricity

Phase 1)
Solar+wind can replace up to ~70% of fossil electricity

It depends on the solar/wind mix, proximity to the equator, grid interconnections, and demand but we are simplifying here.

This is the simple part: just turn off coal+gas when there is enough wind or solar.
But then you run into limits:
1) Solar and wind become worthless when there is an excess (which is increasingly the case)
2) Your grid might not be able to handle the solar or wind peaks
3) Daily demand fluctuations don't match solar+wind
4) Seasonal fluctuations in wind+solar
Phase 2)
Solar+wind+batteries replace up to ~90% of fossil electricity

Batteries can basically solve problem 1), 2) and 3) for you: that is huge!

They can flatten the "Duck curve" to a razor and it's already started in California:…
The reason batteries are now seen as the solution is their spectacular price reduction.

When I wrote a book on electric vehicles in 2008, prices where around $1500/kWh and they didn't last long.

Now we are heading for $50/kWh: 30x less!
See my thread:
This is why @mzjacobson proposed to increase the peak power of hydro back in 2010-2015: it used to be the best alternative before batteries came along.

(Replacing hydro with batteries in his papers was my first reflex, because I live in the Netherlands and wrote about EVs.)
Batteries are also great in the bigger picture: they need materials that are abundant and only use ~0.01% of land surface for mining, which becomes less as you recycle more.

Don't believe the fear mongers who claim otherwise.
By the way: electric vehicles are interesting here too. Not only because they eliminate the need for oil in road transport while reducing energy use by 4x. But also because they need 10x more batteries than the grid and you could use those batteries to flatten the daily curve too
Don't get me wrong:
- Hydro is great!
- Interconnections are often a cost effective way to increase usability of solar+wind
- Some amount of grid reinforcement is certainly needed
- There's lots of other stuff that can help too

We are simplifying here!
For me phase 1) and 2) are a 'done deal': 100% of coal and 90% of gas is near it's expiry date. The current system is a dead man walking that simply doesn't know it yet.

My biggest goal at the moment is make the period it takes to finish phase 2 as short as possible.
E.g. if we transition in 10 years instead of 30 we could:
- Save tens of trillions in wealth loss
- Save millions of people from respiratory illnesses
- Save countless animal and plant species
- Prevent hundreds of millions of climate refugees

This is URGENT
Imagine phase 2 is complete: we have abundant cheap low carbon energy (the sun gives us ~10000x what we need) wherever we want it and daily fluctuations are gone.

Does that mean our entire problem is solved?

No. Because there are longer periods without solar+wind too.
Phase 3)
Solar+wind+batteries+eFuels replace 100% of fossil electricity

The problem of the last 5-10% or so that we are trying to solve involves long duration storage. For that batteries are too expensive, both in terms of money and environmental cost.
Imagine that after phase 2 you have a system that is mostly electricity with a battery that can store 5 hours of average electricity use and is cycled 200-250x per year.

Any idea how much battery capacity you would need to store the maximum fluctuation that happens once a year?
In some places (far from the equator) you need up to TWO MONTHS. That is 150x as much as the battery you need for daily fluctuations. And you only need it once per year.

A battery that is used only once per year is hideously expensive.

So for that use case there is eFuel.
Bringing down the cost of eFuels and finding out what chemistries can be best used in some industrial applications or can be transported most easily is at the forefront of the most exciting research at the moment.

(Even though it's just the last 5-10% of fossil fuel use.)
Of course we could also use biofuels for that, but biofuels are extremely space inefficient: eFuels from PV need ~100x less land and with dual land use wind turbines need ~1000x less land.
California entering phase 2 (=adding batteries) of the transition from fossil fuels to wind+solar is something we should appreciate and cherish.

Too often we think this is all business as usual, while we are in what is arguably the biggest transition in human history.

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More from @AukeHoekstra

Jul 9
With new batteries solar and wind are not only faster and cleaner, but also cheaper.

I'm estimating:
$0.08/kWh for PV+batteries
$0.07/kWh for wind+batteries

@skorusARK gives a good overview of current wisdom, but strongly declining battery prices change EVERYTHING
I've recently written about how I was surprised I missed the enormous consequences of price reductions in batteries.

LFP cells are now $50/kWh and last 10 000 cycles.
That's $0.005 per kWh.

Say we double that to pack the cells and you are at $0.01/…
If you add batteries to solar PV, not all energy has to flow through batteries. But let's keep it at $0.01 and add that to the price of solar. That makes PV (and wind) SUPER cheap!

Batteries must be discounted more quickly you say?
Read 10 tweets
Jun 20
Cheap stationary batteries will pave the way for wind and solar in cheap and resilient energy grids. Unfortunately the @IEA is mispredicting it (again).

Thread based on a free substack article I just wrote.…
Many of my followers know this picture: it visualizes how the IEA underestimates solar. Now I see basically the same problem in their new battery report.

The IEAs new battery report gives a lot of great info on batteries but also two predictions taken from their authoritative world energy outlook:
1) STEPS which is basically business as usual
2) NZE (Net Zero Emissions) which is aspirational…
Read 11 tweets
Jun 16
Batteries: how cheap can they get?

I used the Sunday afternoot to describe how I think that dirt cheap batteries will completely transform our electricity grid, paving the way for solar and wind and replacing grid reinforcements with grid buffers…
This is something I'm working on for different government and grid operator projects, but I never realized just how cheap sodium batteries could become and how much of a game changer that will be.

So I used my Sunday evening to write this and would love your feedback!
First I look at the learning curve and then we see it is extremely predictable: every doubling of production has reduced prices by around 25%.

It's even steeper and more predictable than solar panels, the poster child of this type of learning curve.
(More details on substack.) Image
Read 15 tweets
Jun 5
Aaaand we have another winner of the "EVs and renewables can never happen because of material scarcety" sweepstake. I thought @pwrhungry was more serious. Let me explain why this is misleading bollox.
First of all, notice how his argument is mainly that Vaclav Smil says this and HE is an authority.

Why bother to write a substack that basically parrots someone else?

Because you don't really understand it yourself and needed to write another substack maybe?
I'm a bit tired of this because Bryce abuses Smil the same way most people who are against renewables abuse him. They emphasize this is a serious and revered figure that knows numbers. They make it about the messenger, not the argument.
Read 14 tweets
Jun 1
I wholeheartedly agree with @MazzucatoM that we should better evaluate tech companies contributions.

But the focus on energy use makes a mountain out of a molehill while we have bigger fish to fry.

I see computing as both a huge opportunity and an existential threat.
For me the focus on *how much electricity* an industry uses usually indicates an outdated focus.

We have to get rid of fossil fuels and the mantra is "electrify everything". Because electricity is the form of energy that is usually more efficient and that is greening rapidly.
Many people still can't wrap their heads around the fact that electricity from wind and solar is getting clean, abundant and relatively cheap while we have more than enough materials to make it happen.

IF you focus on datacenter electricity use...
focus on how green it is.
Read 15 tweets
May 24
Cheap batteries are a GAME CHANGER for

We are now moving towards $60 on the cell level for LFP and $40/kWh for sodium ion. $100 for stationary systems in Chine. Using them for demand response will turn the energy system upside down.
You might know that grid congestion is now the biggest problem facing the transition to renewables.

At the same time the grid is used 30% on average.
If you include all the safety buffers on different levels it might decrease to 15%.
The key to unlocking all that excess capacity is

That used to be complicated but with batteries it's relatively simple: just drop some containers with battery cells, connect them to the grid, and make them use a smart algorithm.
Read 10 tweets

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