- [Narrator] We use fossil fuels for energy
because they pack a lot of punch in a very compact form.
Imagine trying to push your heavy car
a kilometer, 3,280 feet,
to the gas station,
when the same task can be accomplished
with just 100 milliliters, less than 1/2 a cup, of gasoline.
Unfortunately gas-powered cars
release a lot of CO2 in that process.
Similarly, in a power plant burning natural gas,
one of the cleanest burning fuels,
it still releases 407 kilograms, or 898 pounds,
of carbon dioxide into the atmosphere
for every megawatt-hour.
Petroleum sources and coal
are 234% and 246% worse, respectively.
Switching to sustainable, environmentally-friendly sources
like wind, solar, tidal, and geothermal
could eliminate all that.
With portable batteries improving daily,
our society is moving towards
a more ubiquitous electrical future.
Storing power from the sun and wind is problematic.
Battery technology has advanced, of course,
but those batteries wear out
and need to be recycled and replaced.
Not only is recycling costly but it's difficult as well
and uses a lot of energy
and generates more CO2 to be released into the atmosphere.
There is a much better way.
Gravity batteries, what are those?
Humans have been using natural gravity batteries
since the beginning of human existence.
Until we evolved intelligence,
we didn't recognize that, of course.
Gravity batteries are built into how our planet works.
You've heard the expression what goes up must come down.
That holds true on any planetary body
where an object doesn't exceed escape velocity.
Technicalities aside, you know that here on Earth
if you place a rock in mid-air
it will accelerate towards the ground
at 9.8 meters, or 32 feet, per second.
Thanks to the Sun, the weather cycle,
and water in plentiful supply,
water rises from low points by evaporation,
deposits at high points by condensation and precipitation,
and flows back to low points by gravity.
This carves rivers, makes new geography,
provides essential moisture for plants and animals,
and transports chemicals and minerals,
making life possible.
Our whole weather system is a gravity battery
collecting mass from a low point,
moving it to a high point,
and then releasing it to do work
and power our whole planet.
And, of course, it's entirely solar powered.
In 1879 the first hydroelectric power generator
opened at Niagara Falls on the Canadian/U.S. border.
At 57 meters, or 187 feet, tall
the Niagara River has a flow of 160,000 meters,
or 5 million feet, per minute.
That provides enough energy to power
25% of the electrical needs
of upper New York State and Southern Ontario
on a continuous basis.
For reference, that's 57 Olympic-sized swimming pools
of water per minute.
That's all well and good,
since Niagara Falls seldom stops flowing, day or night.
That power is available,
rain or shine, light or dark, on demand.
But that's not true with all renewable resources.
Wind power is not continuous in most locations.
Sporadic generation can mean that sometimes
there isn't sufficient wind
to generate enough power for local needs.
If that was the only source,
the local electrical grid would be in trouble.
Some major errors have been made
in building wind farms, too.
In China, at the largest wind farm in the world,
with 7,000 turbines producing 93 gigawatts,
they failed to consider that by turning the turbine blades
the wind was losing power.
As a result of bad alignment,
there are several generators that turn very slowly
at certain times of the day
because of weak used up winds.
Similar to wind, but in a much more dramatic fashion,
photovoltaic solar panel power without external storage
is only usable on sunny days for a limited number of hours.
Problematically, the peak generation often occurs
during off-peak usage periods,
meaning generating capacity is sometimes wasted.
Alternate solar technologies,
such as concentrated solar power, CSP,
uses mirrors to superheat a substance
such as molten salt or oils.
These pass through heat exchangers
to boil water into steam,
driving a turbine generator to make electricity.
The hot media can be stored
and used after the sunlight ceases,
which makes it more convenient and useful.
Still, a few cloudy days could put a real damper
on that storage system,
but even cold doesn't slow it down on clear days.
Geothermal energy, GTE,
is generated by the decay of radioactive elements
far beneath the surface of our planet.
Radioactives formed when neutron stars and black holes
collided long before our own star formed,
and then these elements drifted here,
eventually making up a portion of our planet.
A smaller portion of GTE
also comes from sunlight shining on the ground.
So, except for radio-geothermal,
all of the energy we use comes from the sun.
It's a result of direct solar insolation,
radiated energy from our star,
or something like petrochemicals and coal
that were made using solar energy from previous epochs.
Your local water tower is a gravity battery, too.
Water is pumped up to the highest point in town,
and its mass/pressure is used to move water
throughout the community water system.
This way we don't need pumping stations all over town.
We exploit the physics of pressure being equal
within a closed hydraulic system.
The energy is stored
as gravitational potential energy, GPE,
the what goes up scenario.
Similarly towns and cities in mountainous regions
build reservoirs and pump water uphill
when energy is plentiful and not required.
The first one was built in Switzerland in 1907.
When the need for power increases,
they simply let the water flow back downhill
to drive turbines,
just like Niagara Falls,
but the water movement is manmade,
utilizing generation capacity
that would otherwise go to waste.
Flowing water is used to do work,
it has powered grist mills and sawmills for centuries,
but it's not very efficient,
usually in the neighborhood of 75% or less.
What if we had a markedly more efficient
energy transfer system
with much less waste?
Well, we do.
These are not the typical chemical reaction batteries
we're used to thinking about
such as in cars or in your phone.
It is a purely mechanical battery
that is about 90% efficient.
There are several models of gravity batteries
like the water model mentioned above,
but that is limited by geography.
No mountains means no storage.
What about one that could work anywhere
and doesn't require a massive investment in infrastructure?
This is not a construction crane
out of someone's nightmare.
This proposed unit stores electricity
by converting it into gravitational potential energy.
Three carefully balanced armatures
pick up multi-ton blocks and stack them
until the entire central tower is surrounded in concrete.
It uses unneeded electrical generation
to lift the blocks into place,
and they gain GPE.
When power is required,
the crane picks them up
and then lowers them slowly back to the ground,
turning generators that convert that potential energy
back into useful electric power.
The huge advantage to this system is that it is simple
with well-understood engineering requirements.
It is nearly maintenance-free compared to other systems
and it can be fully automated
to run without any human intervention.
It is also easy to expand by increasing the height.
It has a very small footprint on land,
is ridiculously efficient, more than 90%,
and can store enough energy to power a small town.
Think of it like a giant's Jenga game.
However, since the blocks are not physically connected,
they can shuffle during an earthquake, tested to 8.0.
and remain safe and stable,
so this tower isn't going to fall.
Mines that have been worked out
leave behind long vertical shafts.
By suspending hundreds to multi-thousand-ton weights
in the shaft,
energy can be stored by raising the weight
to the top of the shaft
and then released by lowering it again,
turning generators.
Depending on the weight's mass,
lowering it just a meter, or a yard,
could power a town for an hour.
However, placing one is dependent
on there being a used up mine nearby.
On the other hand,
constructing a shaft deliberately could be considered.
A solid block of stone,
raised and lowered hydraulically,
would be more efficient than water alone.
A rock cylinder 250 meters, or 820 feet, in diameter
and 250 meters tall
could store eight gigawatts of power,
say about six trips in a time-traveling DeLorean,
or enough to power six million average homes,
at 750,000 houses per gigawatt.
In a shaft one-kilometer tall,
moving from top to bottom at two centimeters per second
would take 14 hours.
Multiple smaller weights would be able to store more
and operate for longer periods.
While a single large weight could provide
hundreds of megawatts in just seconds
to balance power grids and meet sudden demands,
it would only need to move centimeters or inches per second
to do so.
Right now the timeline for achieving
net positive fusion energy
is somewhere in the 2030s,
but that is simply attaining the goal.
It may not be commercially viable
for another couple of decades after that,
or even a century.
ITER, International Thermonuclear Experimental Reactor,
involving 35 nations,
is a cooperative fusion testbed in France
sitting on an area equivalent to 60 soccer fields.
It is a single location, costing billions so far,
weighing 23,000 tons,
will require 150 million degree temperatures
to achieve fusion,
and is not designed to be a commercial producer.
It's an experiment.
A small company in the UK called Tokamak Energy
using a much simpler system
has achieved 100 million degrees,
sufficient to trigger fusion in the smaller machine.
Its cost totals $70 million to date instead of billions.
You could put several of these on a soccer field.
Could fusion, or many other similar projects,
make gravity batteries irrelevant?
Sure, in about 30 years or so,
but we don't have 30 years to wait.
We need to reach net-zero carbon emission ASAP
to have a chance to moderate or halt
dangerous climate change.
Energy without resource to fossil fuels is already possible.
Norway obtains 98.4% of its energy that way,
followed by Brazil, 84.1%,
New Zealand, 80%, Sweden, 68.4%,
and Canada, 67.7%.
The last five of the top ten are Columbia, 64.8,
Venezuela, 60.9, Portugal, 59.7,
Chile, 48.2, and Germany, 44.5.
Sadly, the U.S. sits at only 12.6% from renewables,
less than half of Mexico's 26%.
The energy sector is still strongly resisting change.
Other than that old-school industry resistance,
the two big practical problems
have always been storage and delivery.
Gravity batteries solve both problems
because when we have a method to store energy effectively,
green energy generation should climb right along with it,
and these gravity batteries fit
into just about any environment.
Gravity batteries already have working models
by many companies around the world.
The demonstration unit by Energy Vault
is just 60 meters high,
but their basic 120-meter unit
can store 20 megawatt-hours,
or enough energy for 2,000 homes for a day.
Energy Vault's concrete blocks are 23 metric tons each.
In terms of money and technology,
it is simple to build and operate.
Another advantage for gravity batteries
is that they can store any electrical energy provided.
If we happen to switch
to orbiting geosynchronous solar power satellites
that collect much more energetic solar radiation
from well above the Earth's atmosphere
and beam it down by microwave,
then gravity batteries can happily accept that, too.
Incidentally, capacity in not controlled
just by sheer height.
You can also build outwards.
You can have as many layers as you like
as long as the lifting mechanism can reach that far.
The point is that we can step away from fossil fuels now.
Gasoline cars will go away by attrition,
replaced by electric vehicles over time.
Power plants burning coal, fuel oil, and natural gas
can be supplanted by renewables
as they shut down due to age.
We simply won't replace them.
Natural gas plants last 20 to 30 years
and most are halfway there already.
The same can be said for petroleum-fueled oil power plants,
lasting 40 years,
and coal-fired plants, lasting 50 years.
And many are approaching retirement age.
Chemical batteries are expensive, have short lifespans,
and are both expensive and difficult to recycle.
We'll always need them for mobile applications,
like car batteries or remote locations.
Gravity batteries are the clear winner in terms of cost,
durability, reliability, well-understood engineering,
and limited environmental impact.
We can do what is needed right now at low cost,
or we can wait until all our coastal towns are underwater.
Which will you choose?
Let me know in the comments below.
If you enjoyed this video,
please check my other video
on five emerging battery technologies
that will change our world.
Thanks for watching, I'll see you next time.