We’re here to talk about one complex topic: the future of Earth’s energy. Where does it go next? That’s a decision that you and your family probably get to be a part of!
Let’s begin with what Earth’s energy needs are.
It is estimated that powering Earth for one year requires somewhere between 18 and 20 terawatts—or 18 to 20 trillion watts. If you can imagine around 200 billion standard light bulbs all burning at once, you’re starting to get the idea!
Yup, our energy needs are huge. And growing quickly.
For almost 200 years, we have fed these needs primarily with fossil fuels—coal, oil, and natural gas. Have a look at Canada’s energy breakdown:
- Oil: 31%
- Natural gas: 28%
- Hydroelectric: 26%
- Nuclear: 7%
- Coal: 6%
- Others (wind, solar, etc.): 2%
An exhausting conversation
The fossil fuels listed above make up 65% of Canada’s energy. But they have two major strikes against them.
First, they are exhaustible, meaning they can one day run out.
Second is their exhaust itself. Burning fossil fuels sends tons of greenhouse gases into our atmosphere and is a leading cause of climate change.
It’s clear that at some point, we need to commit to more Earth-friendly energy sources that are:
- Renewable (will not run out)
- Clean (as close to zero carbon emissions as possible)
Put these two things together and you get sustainable energy—sources that can be used continually without negative consequences for the planet. That’s the goal!
What is sustainable?
Right now, the two greatest hopes of sustainable energy are:
- Solar: using panels to capture the energy of the Sun
- Wind power: using wind to turn giant turbines
Another option is geothermal, which uses steam from hot springs to power turbines. However, hot springs are relatively rare, so they cannot be a worldwide power source. Meanwhile, solar and wind are appealing because sunshine and breezes are found just about everywhere.
But critics say that these forms of power are not practical as our main source of energy for three main reasons:
- Their power plants take up too much space
- The energy they produce is too costly
- They’re unreliable
We had to ask: Is that true?
Not so bad
It is true that solar panels and wind turbines both need a lot of room to function. But studies have been done to estimate how much space would be required to generate the 20 TW of power we need to cover Earth’s energy bill. And it’s not so bad.
- Solar: If we covered around 2% of the Sahara desert—a place with year-round sun and almost no clouds—in solar panels, we could produce 20 TW.
- Wind: We would need around 3.9 million turbines to power humanity. Spaced apart at a reasonable distance, that would be about the area of Spain.
Of course, no one is talking about clustering all of our power plants in one small corner of the world! That would be silly. But not having enough room doesn’t seem to be a problem.
Actually affordable? Really reliable?
The biggest concerns with solar and wind are price and reliability.
Natural gas is currently one of the cheapest forms of reliable power in the world. Depending on where you live, natural gas can be around half the price of wind and a quarter of the price of solar. Are people willing to pay four times as much for their power?
And then there’s reliability. What happens when the wind dies down? Or when we run into a patch of cloudy skies? These are fair concerns.
Technology is catching up
Supporters of solar and wind energy remind us that these are still new technologies. The solar panels and wind turbines of today are already many times more efficient than those of even five years ago. Meanwhile, battery technology—which is used to store excess energy for later use—is also improving dramatically.
As this technology gets better, reliability and efficiency increase, and costs go down. Want proof? In 2016, solar plants in Chile produced way more energy than expected, making it cheaper than expected as well.
Okay, so sustainable energy can provide 100% of the energy needed by Earth. Might it cost more at first? Will it be a little awkward getting to that goal?
In the meantime, we need reliable, powerful, and cheap energy sources to keep the lights on (all 200 billion of them!). But if we’re looking for a greener way forward, it’s good to know that options already exist!
Stay tuned for our second story in this special Project Planet series! Come back on Thursday, April 12 to read "Keeping Our Cool: Can the Ice Caps Recover?"