Sponsored by Brilliant. While renewable energy sources like
solar and wind have now become cheaper than fossil fuels , developing long-term energy storage is key
to overcome their intermittency. Lithium-ion batteries are the state-of-the-art storage
technology but they can only cost-effectively provide energy for about 6 hours. So, what if we
could extend the battery duration to 100 hours ... out of thin air ... and rust? Literally!
I'm Matt Ferrell ... welcome to Undecided.
Solar and wind energy adoption is growing, but they'll never be available 24/7.
On top of that, climate change-induced extreme weather events like storms can cause several
days of power outages. The booming demand for a more secure and cleaner energy supply
is driving the need for storing surplus green energy, so that it can be fed back to the grid
on a cloudy day or when the wind isn't blowing. To quench the thirst for carbon-free power,
grid operators are investing in today’s most mature storage technology:
lithium-ion batteries. In the US, the scale of these installations is expected to grow
from a *current* level of 1.5 gigawatts up to hundreds of gigawatts by 2030.
After the last heatwave-induced blackouts, California has been *warming up* the race to
energy storage. Last year, Vistra Energy began developing the world’s largest battery with a
300-megawatt capacity of lithium-ion battery technology. Along with another 100-megawatt
storage unit scheduled to go online this year, the Californian plant will provide energy to
about 300,000 homes for four hours during evenings, or whenever a power outage occurs.
But what if demand outstrips supply for 24 hours or even for a few days? Lithium-ion systems are
better suited for delivering short-term bursts of energy. The downside, their charge dissipates over
time and you'd need many of them to provide energy over a longer period of time. While lithium-ion
batteries are already at commercial scale, their levelized cost of storage (LCOS) doesn't scale
well. We're talking about $132-245/MWh for large-scale applications according to Lazard.
You can probably see why a cheaper, long-duration energy system would come in handy.
So, is there anything like that? Form Energy seems to have something *in storage* for us.
The Massachusetts-based startup has developed a rechargeable iron-air battery. This technology
isn't exactly new. NASA was the first at playing around with it back in 1968, but it was never
commercialized because of technical challenges with its components, such as the electrodes and
electrolytes. For example, NASA struggled with the hydrogen formation at the anode.
Because of this, the electrode had to be overcharged to reach its full capacity.
Form Energy has spent years fine-tuning the process and said its innovation will let us have
low-cost renewable energy every day of the year. Dubbed as a multi-day storage solution,
Form’s batteries can store large amounts of energy and release it over more than four days.
This storage option could tackle the day-to-day and seasonal variability of renewable production.
The company managed to close $240 million of series D funding by attracting big investors
like Jeff Bezos, Bill Gates’ Breakthrough Energy Ventures, and ArcelorMittal, which is one of the
world's leading iron ore producers who will help Form Energy generate the raw material.
But how does Form Energy's battery work? Think of a box filled with racks of 10 to 20 cells.
Every cell is filled with an electrolyte solution, similar to the one used in AA batteries,
and two plates: an anode made of iron pellets and an air-breathing cathode. This setup allows
an electrochemical redox reaction to happen. Essentially, Form Energy's battery stores
electricity through a reversible rusting cycle ... yes, rust. They turn corroded iron pellets into an
energy dispenser. The way it works is actually pretty simple. When they expose the tiny iron
pellets to air, oxygen will turn them into rust, a.k.a. iron oxide. That oxidation releases
electrons, which is the electricity that can be sent to the grid. To charge up the battery,
you basically reverse that process. The incoming electrons will *eat up* the oxygen and reduce the
rust layer until it converts it back into metallic pellets. Thanks to this ... e-looping ... process,
the iron-air battery can store energy for much longer than conventional setups.
The benefits of this type of technology could be absolutely massive.
No matter if you’re in Pittsburgh, the cloudiest city in the US
or in Oak Ridge, Tennessee, where the wind is calmer than anywhere else in America.
You could store and have 100% clean energy for at least 4 days. Forget about fossil fuels backup.
But the thought of that probably raises another question in your mind,
how do iron-air batteries stack up against other energy storage systems?
If you compare them to lithium-ion batteries, the gold standard in power storage,
Form Energy's device boasts a 17x longer duration. Based on a recent study , a 100+
hour storage system could have a huge impact on reducing the power generation costs.
Although Form hasn't put a price tag on its invention yet, they claim that technology
improvements paired with using extremely abundant materials like Iron and air would make their
batteries 10 times cheaper than lithium-based systems. If they managed to go below $20/kWh,
the integration of their batteries in our energy systems could save billions in electricity costs.
Besides being more widely recycled, Iron is the fourth most common element on
Earth , while lithium is about 2,000 times less plentiful. You may see why the production of
Form Energy's batteries are more sustainable than lithium-based devices in the long run.
And it’s also safer. That’s because the electrolyte solution isn't flammable,
unlike the mixture of lithium salts and organic solvents inside typical lithium-ion batteries.
On the other hand, Form Energy doesn't see their batteries as a replacement for lithium-ion storage
systems, but as a complement to them. Lithium-ion batteries are great for fast-response actions like
frequency regulation and grid stabilization. They also have a high power-to-weight ratio
or energy density. That means they can hold a lot of energy while keeping a small size,
which is ideal for electric vehicles (EVs). In contrast, Iron-air batteries would be best at
storing and supplying large amounts of energy at lower power and density. Which makes sense
given their *dishwasher size* they’re no where near fitting inside your smartphone
and are nearly as large as your EV. Instead, they’re designed to be hooked together in grids.
But Form Energy isn't the only one working on long-duration batteries.
The Oregon-based company ESS built a factory producing iron flow batteries back in 2019.
One of the company’s key achievements was to invent a Proton Pump that recycles the unwanted
hydrogen from the anode into the electrolyte solution. By recirculating protons into the
liquid phase, the pump rebalances the chemistry of the electrolyte and maintains its conductivity,
which preserves the battery efficiency. ESS has recently launched a new scalable
and custom-designed system starting from a power capacity of 3 MW. However,
their commercial plant can continuously supply electricity for only 16 hours at most.
And it’s not just about Iron. The Canadian start-up Zinc8 has developed a Zinc-air
battery that can also provide 100+ hours of storage. This works pretty much the same way
as the Iron-air system, except you store the energy in Zinc particles which are as big as
grains of sand rather than in Iron pellets. When you need electricity, you combine the charged
Zinc particles with the oxygen from the air and water to form zincate, an oxidised form of zinc.
That probably helps make sense of the companies name. This is then broken down upon recharging to
close the loop. Same principle but different price as the capital cost of a 100-hour
Zinc8 battery is $60/kWh , which is above the $20/kWh threshold Form Energy may go under.
Nevertheless, Zinc8 has been working towards three pilot projects.
A problem with Zinc is that it’s more prone to form dendrites compared to Iron. These crystals
pile up onto the anode over time damaging the electrode and affecting its durability.
Besides Iron and Zinc, Aluminium is another active element that could be used in the metal-air
battery setup. I've actually got a video I put out a few weeks ago on this topic. Aluminium-air units
are touted to have high energy density and to be cheaper and safer than lithium-ion batteries.
This places them as a potential alternative to lithium packs in EVs. While you can’t recharge the
Aluminium-air battery, you could swap it for a new one at the fuel station and recycle the old one.
Looping back to the iron-air system, Form Energy touts flexibility as another plus for
their technology. Based on the energy demand, tens of thousands to hundreds of thousands of modules
can be grouped into megawatt-scale power blocks. Their modular plants can be built anywhere,
including urban areas, targeting utility-scale energy needs.
All this sounds *electrifying*, right? But will it actually work? It's a little too
early to tell since the US startup isn't launching its first pilot until 2023.
They'll build a 1MW plant at the Great River Energy utility's Minnesota facility. It's going
to take reaching a commercial scale before we’ll know the real feasibility of iron-air batteries.
According to some researchers, this storage unit should reach an efficiency of 80%
and have a cycle life of 5,000 cycles to withstand a commercial operation.
As of today, Form Energy seems to be keeping the efficiency and durability of their devices
behind an *iron curtain*, however, the company appears to be focusing on tech-savvy work.
Besides optimizing the electrodes manufacturing and the cell design,
modeling plays a key role. Form Energy appears to be ahead of the simulation game with their
grid modeling tool, Formware™. By factoring real-world weather variability across the year
with hourly resolution, the company toolkit could help design more reliable, cost-effective and
clean power systems that deliver around-the-clock electricity. One of the practical applications of
their tool was to assess whether long-duration storage units could cost-effectively replace
the energy supply of peaker plants in New York State between 2010 and 2019. According to their
estimates, low-cost multi-day batteries would economically match the operations of 83% of New
York’s plants. In addition, using long-duration storage along with lithium-ion batteries would
enable replacing 4 times more peaker plants compared to using lithium-based systems alone.
Based on data from one of their partners, Form Energy conducted some case studies to compare the
cost-effectiveness of their higher time resolution model with a standard method using a lower number
of data points. Results show that Form Energy’s more accurate approach would save grid users
$27 million per gigawatt of peak demand per year. That's because Formware captured
renewables variability across the year much better than the conventional model.
Long-lasting energy storage will be essential to increase the utilization of renewables and
leave fossil fuels underground. Combined with lithium-ion batteries, the Iron-air systems
could accelerate the transition to carbon-free electricity. While its feasibility still needs
to be proved out, this technology holds a lot of promise for recharging the planet’s batteries.
If you're interested in learning more about the principles behind Iron-air batteries or
how Form Energy can develop software that accurately predicts performance,
I'd strongly recommend checking out the Applied Probability course at Brilliant.
I calculated that you'll enjoy this course. I learned how we're able to model the unpredictable
world around us. How we're able to calculate outcomes, create weather models, and understand
probability in science. It's a fun one that really helped me wrap my head around a lot of this.
But even if that course isn't for you, there's a very high probability that they'll have something
you'll enjoy. They have over 60 courses including topics in scientific thinking,
quantum mechanics, and applied science. They've got something for everybody.
All of the concepts are taught through fun and interactive challenges to help you understand
the "why" of something ... not just the "how." It helps to develop your intuition,
which is my favorite part about Brilliant and taps into the way I learn ... and just makes it fun.
Go to www.brilliant.org/Undecided to sign up for free. The first 200 people will get 20% off their
annual premium membership. Thanks to Brilliant and to all of you for supporting the channel.
What do you think? Do you think Iron-air batteries have a shot at becoming one of the go-to energy
storage technologies for the grid? Jump into the comments and let me know. And if you liked
the 3D animations explaining how the battery works, check out Serge Sorokin (sow-row-kin)
at sergefx.com. He's an incredible animator and I highly recommend his work. And a special
welcome to new Patreon Producers Calvin Vette, TJ Thompson, and the Norcross Family and Supporter+
member Armando Miraglia. Your direct support on Patreon really helps with producing these videos.
Speaking of which, if you liked this video be sure to check out one of the ones I have
linked right here. And subscribe and hit the notification bell if you think I’ve earned it.
Thanks so much for watching and I’ll see you in the next one.