What does the world's largest machine do? - Henry Richardson
On February 7th, 1967, Homer Loutzenheuser
flipped a switch in Nebraska
and realized a dream more than
five decades in the making.
The power grids
of the United States joined together,
forming one interconnected machine
stretching coast to coast.
Today, the US power grid is the
world's largest machine.
It contains more than 7,300
electricity-generating plants,
linked by some 11 million kilometers of
powerlines, transformers and substations.
Power grids span Earth’s continents,
transmitting electricity around the clock.
They’re massive feats of engineering—
but their functioning depends
on a delicate balance.
Their components must always
work in unison,
maintain a constant frequency
throughout the grid,
and match energy supply with demand.
If there's too much electricity
in the system,
you get unsafe power spikes that can
overheat and damage equipment.
Too little electricity
and you get blackouts.
So, to strike this balance,
power grid operators monitor the grid
from sophisticated control centers.
They forecast energy demand
and adjust which power plants are active,
signaling them to turn their output
up or down
to precisely meet current demand.
By considering factors like the
availability and cost of energy resources,
grid operators create a “dispatch curve,”
which maps out the order in which energy
sources will be used.
The grid defaults to using energy
from the start of the curve first.
Usually, the resources are
ordered by price.
Those at the start tend to be renewables
because they have much lower
production costs.
Some grids, like those
in Iceland and Costa Rica,
run on more than 98% clean energy.
But most dispatch curves contain
more of a mix
of carbon-free and carbon-emitting
energy sources.
This means that where your electricity
is coming from—
and how clean it is—
varies throughout the day—
as often as every few minutes.
Take the state of Kansas.
Despite having plentiful wind resources,
it regularly relies on carbon-emitting
power plants.
This is because wind energy is especially
plentiful at night.
But, this is also when
there’s lower demand.
So, Kansas’s wind energy
is actually regularly disposed of
to prevent excess electricity
from damaging the grid.
And comparable scenarios
add up to a big problem worldwide.
Thankfully, dependence on renewables
is rising.
But power grids are often unable
to make full use of them.
Many simply weren't designed around
intermittent energy sources
and can't store large amounts
of electricity.
Researchers are experimenting
with unique storage solutions.
However, this will take time
and substantial investment.
But hope is not lost.
We have the opportunity to work with
our existing power grids in a new way:
by shifting some of our energy use
to the times when there’s clean
electricity to spare.
Leaning into this concept,
called “load flexibility,”
we can help flatten the peaks in demand,
which will place less stress on the grid
and reduce the need for non-renewables.
So researchers are developing
automated emissions reduction technologies
that tap into energy use data
and ensure that devices get electricity
from the grid at the cleanest times.
In fact, smart devices
like this already exist.
So, how big an effect could they have?
If smart technologies like
air conditioners, water heaters,
and electric vehicle chargers were
implemented across the Texas power grid,
the state’s emissions could
decrease by around 20%.
In other words, simply coordinating
when certain devices tap into the grid
could translate to 6 million fewer tons
of carbon
released into the atmosphere
annually from Texas alone.
Now, imagine what this could look like on a global scale.
Now, imagine what this could look like on a global scale.
