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[INTRO ♪]
Telling people that buying an electric car
is a great way to fight climate change is
a pretty reliable way to start an argument in some circles.
People will say that you still burn fossil fuels
with electric cars – it just happens
at the power plant instead of the engine.
And while that's at least partly true,
over their lifespans, electric cars don't consume
anywhere near the fossil fuels that
gas-powered cars do — especially in the United States.
With electricity getting cleaner all the time,
they're even better than you might expect.
There are a few variables to keep in mind though,
starting with the cars themselves.
In the US as of 2016, the average pure-gasoline
passenger car goes about nine kilometers
for each liter of gas it burns,
or about twenty-two miles per gallon,
but that's just an average.
Some go four kilometers or so; others go fourteen.
But the fuel efficiency hits higher highs,
and lower lows, when we start talking about
hybrid cars or trucks on the interstate.
Plus, the act of manufacturing a car
leads to greenhouse gas emissions --
whether it's electric or not.
So does refining gasoline.
But the major complicating factor here is electricity.
And where you live determines
how clean your electricity really is.
Most electricity in the US uses a combination
of natural gas, coal, and nuclear fission –
with a bit of water, wind, solar, oil,
and a few others thrown in.
But those numbers change from state to state,
and depend on things like local natural gas sources
or how windy it is today.
For example, Alaska has plenty of natural gas
and hydroelectric resources, so its power plants
create very little waste when generating electricity.
That means a full electric vehicle charge
using Alaskan electricity creates roughly
the same emissions as a gas engine that
drives 48 kilometers per liter or 112 mpg.
That's roughly five times the national average,
and two or three times better
than even some of the best hybrids.
It's pretty efficient!
But at the other extreme are places like Colorado,
which, energetically speaking,
is one of the dirtiest states. Sorry Colorado.
About half of Colorado's electricity is from coal,
which produces more emissions
than just about any other source.
But even there, electric cars
still outperform gas cars.
A full charge off of Colorado electricity
equates to about twenty kilometers per liter (46 mpg) –
about double the national average, based on 2016 figures.
That's pretty good.
Better still, most of the country is closer
to Alaska's numbers than Colorado's.
It comes down to this:
Power plants are just better at making power
than car engines are.
One reason is that they're simply bigger.
Bigger things don't waste as much energy staying hot
-- and that makes them more efficient.
And the story is similar across most of the world,
although again the details change depending on
where your electricity comes from.
In countries that tend to use more coal,
like India or China, electric cars break even
with the average gas-powered car in the US —
although they're still less efficient
than the average Indian gas-powered car.
But in water-powered Paraguay
or geothermal-rich Iceland,
gas engines need to get more than
90 kilometers per liter to beat an electric one.
So are electric vehicles really more efficient than gas?
Yes, they absolutely are –
unless you have some very dirty electricity.
So much for the “well, actually”s.
But climate change isn't just one problem;
it's a hot mess of many problems at once.
And it'll take some pretty radical changes
from people all over the world to keep that
hot mess from getting even hotter.
Thanks for asking.
Before you go, you may or may not be aware
that I wrote a book!
And that book… is out in paperback now.
I didn't tell you about it when it was just hardcover,
but now you can get it in value discounted,
not-as-hard edition!
It's a book about a girl who gets famous on the internet,
which is something I know a little bit about.
And it's also about like, space aliens, some.
So if sci-fi mixed with fame destroying people
sounds like an interesting story to you,
check it out! It's available wherever books are sold.
It's called An Absolutely Remarkable Thing.
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