How much land does it take to power the world?
No matter how we make electricity,
it takes up space.
Electricity from coal requires mines,
and plants to burn it
and convert the heat into electricity.
Nuclear power takes uranium mines,
facilities to refine the uranium,
a reactor, and a place to store
the spent fuel safely.
Renewable energy needs wind turbines
or solar panels.
How much space depends
on the power source.
Say you wanted to power a 10-watt
light bulb with fossil fuels like coal.
Fossil fuels can produce
up to 2,000 watts per square meter,
so it would only take a credit card-sized
chunk of land to power the light bulb.
With nuclear power, you might only
need an area
about the size of the palms of your hands.
With solar power, you’d need at least
0.3 square meters of land—
twice the size of a cafeteria tray.
Wind power would take roughly
7 square meters—
about half the size of a parking space—
to power the bulb.
When you consider the space needed
to power cities, countries,
and the whole world,
it adds up fast.
Today, the world uses 3 trillion watts
of electricity.
To power the entire world
with only fossil fuels,
you’d need at least about 1,200
square kilometers of space—
roughly the area of Grand Bahama island.
With nuclear energy, you’d need almost
four times as much space at a minimum—
roughly 4,000 square kilometers,
a little less than the area of Delaware.
With solar, you’d need at least
95,000 square kilometers,
approximately the area of South Korea.
With wind power, you’d need two million—
about the area of Mexico.
For each power source, there’s variability
in how much power
it can generate per square meter,
but these numbers give us a general
sense of the space needed.
Of course, building energy infrastructure
in a desert, a rainforest, a town,
or even in the ocean
are completely different prospects.
And energy sources monopolize the space
they occupy to very different extents.
Take wind power.
Wind turbines need to be spread out—
sometimes half a kilometer apart—
so that the turbulence from one turbine
doesn’t reduce the efficiency
of the others.
So, much of the land needed
to generate wind power
is still available for other uses.
But the baseline amount of space
still matters,
because cities and other densely populated
areas have high electricity demands,
and space near them is often limited.
Our current power infrastructure
works best
when electricity is generated
where and when it’s needed,
rather than being stored or sent
across long distances.
Still, space demands are only
part of the equation.
As of 2020, 2/3 of our electricity
comes from fossil fuels.
Every year, electricity generation
is responsible for about 27%
of the more than 50 billion tons
of greenhouse gases
we add to the atmosphere,
accelerating climate change
and all its harms.
So although fossil fuels require the least
space of our existing technologies,
we can’t continue to rely on them.
Cost is another consideration.
Nuclear plants don’t emit greenhouse gases
and don’t require much space,
but they’re way more expensive to build
than solar panels or wind turbines,
and have waste to deal with.
Renewables have almost no marginal costs—
unlike with plants powered
by fossil fuels,
you don’t need to keep purchasing fuel
to generate electricity.
But you do need lots of wind and sunlight,
which are more available in some places
than others.
No single approach will be
the best option to power the entire world
while eliminating
harmful greenhouse gas emissions.
For some places, nuclear power
might be the best option
for replacing fossil fuels.
Others, like the U.S.,
have the natural resources
to get most or all of their electricity
from renewables.
And across the board, we should be working
to make our power sources better:
safer in the case of nuclear,
and easier to store and transport
in the case of renewables.
