- Batteries make a lot
of modern tech possible.
Everything from cell phones,
cameras, medical devices,
a million appliances, to bigger
things like electric cars.
You might get frustrated
because your cell phone still
can't make it through the day
on a single charge, but the fact is,
battery technology as a
whole is leaping forward.
It's improving so much that batteries
aren't just powering
our phones and our cars,
they're powering cities
and even replacing entire power plants.
But storing energy on the
power grid isn't a new idea.
In fact, batteries are joining
some really whimsical technology.
Tech that might make you wonder
what the definition of
a battery actually is.
(light music)
- Well, storage has been
sort of the Holy Grail
of the electric grid
or electricity industry
for a very long time, decades, really.
- [Cory] JB Straubel is a
co-founder of Tesla and its CTO.
Tesla, obviously, is big into
batteries for their cars,
but they're also tackling
city-sized energy storage,
which improves on our
very old school grid.
- You know, the electric
grid hasn't changed that much
from 100-some years ago
when Tesla and Edison
were actually inventing it.
Most people don't realize, but
it's instantaneously matched.
Every time that you turn on
a light switch in your house,
instantaneously, a power plant,
somewhere, connected to that same grid,
has to ramp up a little more power output
to make the light operate.
- When you turn on that light,
you're probably relying on
a big old gas or coal fired plant.
Fossil fuels account for about
60% of electricity in the U.S.
and another 20% comes from nuclear.
Big plants are steady, but
they're not very flexible.
- Generally, to power something,
you have these huge base load gas plants.
- [Cory] That's The
Verge's own Angela Chen.
- And these are running
kind of all the time,
no matter what and they're pretty slow
and you can't really adjust how much
energy they're creating.
- When demand is too low,
these big, slow plants
actually lose money.
And when demand is too high,
quicker, dirtier plants
called peaker plants have
to switch on to keep up.
And they're pretty wasteful.
- So you kind of get dinged on both sides.
You get dinged when you
don't have enough load
and then when you have too much,
you also get dinged inefficiently.
- So, traditional plants
aren't super efficient,
but they're consistent
and therefore predictable.
Renewable energy can be another story.
Solar and wind power is cheap
and clean and plentiful,
but only when the sun is
shining or the wind is blowing.
- So, inconsistency is the big worry,
that, you know, it'll be a cloudy day
or it'll be a still day
and then all of the sudden,
your appliances won't work
and that's something that
no one really wants.
- What makes batteries so promising
is that they can solve
all of these problems.
When paired with big power plants,
they can supply energy during peak times
without polluting the way
that peaker plants do.
And when paired with renewables,
they can jump in when clouds
roll over a solar farm.
Energy storage really is the
missing piece of the puzzle
for renewable energy.
But when we say storage,
we don't just necessarily mean these.
On a super broad level, a battery
is like a bank for energy.
You deposit energy into
it when you don't need it
and withdraw it when you do.
We use electrical energy on the grid,
but we can store it as any kind of energy.
Exhibit A: the Hoover Dam
is in the news right now
because of plans to turn
it into a giant battery.
It would work by converting
excess electricity
into gravitational potential energy.
- So, essentially, you have two lakes.
There's one at the bottom
and there's one at the top.
And then, when the energy is cheap,
you can pump water from
the bottom to the top
and it kind of just stays
there in the reservoir.
And then when you need the energy,
you open up the reservoir
and the water goes
crashing down and it turns this turbine
and it creates this extra energy
that you might need for high demand.
- This is called pumped
hydro-electric storage
and it's actually in use
all over the country today.
But there are other options.
Flywheel storage works the same way
that this little toy car does.
Engineers use power to start
a heavy flywheel spinning
and that power gets stored via inertia.
You can later harvest that inertia
to generate electricity again.
And weirder still is
compressed air storage.
Cheap power is used to
force air into a cavern
or a canister, building up pressure.
When power gets pricey or scarce,
you can release the air to spin a turbine
and power a generator.
But then, there's the big newcomer.
Gridscale chemical batteries.
In the past few years,
the price and durability
of batteries have improved fast,
making them suddenly useful
for variable energy sources like solar.
- That was kind of
unheard of 10 years ago.
If you told someone that,
hey, a lithium ion battery
could do that sort of
duty, storing solar energy
every single day for 10 years,
they wouldn't have believed it.
- Batteries are still a tiny fraction
of the energy storage market.
This is roughly the market
share that pumped hydro waves.
And this is everything else.
But within that everything else,
batteries are growing fast,
partly because they work at any size.
- Well, I think the biggest
thing is scalability.
Batteries have this beautiful ability
to vary economically,
scale from gigawatt hour
size of systems all the way
down to 10 kilowatt hours
in your house.
- Batteries do have their weaknesses.
They degrade over time,
which you've probably
noticed about your cellphone.
And you can't run them indefinitely
the way that you can a fueled power plant.
Once the charge is depleted, that's it.
But their flexibility sets
them apart from pumped hydro
which is really only practical
on the scale of a lake.
The point is, big batteries let us do
a couple of exciting things.
They let us spread out the responsibility
of getting power to where it's needed.
And they help patch together
the mixed bag of power sources
that we're juggling right now.
- I think what you're seeing now
is you used to have an entire city
would be powered by, you know,
two or three huge power plants.
And now you're seeing
it's more distributed,
so there's definitely a role we can have
some of your energy from solar,
some of your energy from the grid.
It doesn't have to be one or the other.
- Of course, the dream of green energy
isn't a mix of fossil fuels
and other technologies.
It's 100% renewables like solar and wind.
But if we're going to go all the way,
we're going to need a lot more batteries.
Hey everyone, thanks for watching.
If you liked this video, please be sure
to check out all the other
videos on our channel
and don't forget to subscribe.
(deflating)
- Yeah!
(laughing)
- So good.
- That was great.
