In my (Dutch) newspaper @trouw, mobility historian Vincent Vinne proclaims electric cars are unsustainable because they have lots of power and can drive fast.
Let me explain (again) why these things are actually beside the point for electric cars. trouw.nl/opinie/waarom-…
Basically it's very simple: regular combustion engines get less efficient when they don't perform at their optimal power number of rotations per minute. You can see this in a BSFC plot.
On this map optimum is >250 g/kWh but it can increase to 475 g/kwh. x-engineer.org/brake-specific…
So this means that a powerful engine (with a high top speed) is usually used at an optimal of say 70% of max power but only at 10% which then doubles energy use.
So historically speaking, mobility historian Vincent Vinnes is right. More power and topspeed is energy inefficient!
For a combustion engine in a practical car 35% optimal efficiency is pretty good. In the city it can easily drop to 10% or so: >200% more fuel use.
For EVs it works similarly but the impact is small. E.g. efficiency drops from 92+% to 86%: 7% more energy. x-engineer.org/electric-vehic…
To make an issue out of the marginal extra energy use because of their top speed and acceleration betrays a fossil mindset.
(You could argue fast cars are less safe and driving at higher speeds does use more energy by the way. But these are very different issues.)
This doesn't mean electric vehicles are optimally sustainable! By making them larger and heavier and by not sharing them we use much more energy and material than is optimal!
So the Dutch head of state travels a lot more sustainably!
But let's put the focus where it belongs. When you want sustainable transportation, forget about making electric vehicles less powerful and slower (it hardly helps) and focus on making them smaller, lighter and shared.
/end
This should have been: an engine performs optimally at around 70% so a powerful engine that is usually used at much lower power (say 10%) will use twice as much energy as optimally possible in daily use.
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Cheap stationary batteries will pave the way for wind and solar in cheap and resilient energy grids. Unfortunately the @IEA is mispredicting it (again).
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 iea.org/reports/batter…
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 aukehoekstra.substack.com/p/batteries-ho…
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.)
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.
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.
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
Cheap batteries are a GAME CHANGER for
GRID CONGESTION and for SOLAR and WIND
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.
🧵
The key to unlocking all that excess capacity is
DEMAND RESPONSE
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.