Why aren't we harnessing this energy?
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00:00 What if I told you that
00:05 what lies beneath these mysterious pools
00:08 could access 17 billion years' worth of energy?
00:13 Imagine no longer needing fossil fuels,
00:16 while having an energy source
00:18 that could battle climate change.
00:21 What is geothermal power?
00:25 How much energy is actually available?
00:28 And why aren't we harnessing this energy?
00:32 This is WHAT IF,
00:34 and here's what would happen
00:36 if we ran the planet on geothermal power.
00:40 It has the potential to power the world,
00:43 and it's cleaner and more reliable
00:45 than any other energy source.
00:48 It seems strange that we're not already
00:51 using this all over the globe, right?
00:54 First, let's explain what's actually under
00:57 these strange pools you're soaking in.
01:00 Beneath the Earth's crust,
01:05 there's a layer of hot and molten rock
01:08 called magma.
01:10 Heat is continually produced in this layer
01:13 by the radioactive decay of thorium,
01:16 uranium, and potassium at the Earth's center.
01:20 Heat is also generated by the friction
01:22 along the margins of the shifting continental plates.
01:26 We see this heat from the Earth's interior
01:28 as it generates phenomena on the surface
01:30 like geysers, hot springs, and lava flows.
01:35 The extreme amount of heat
01:37 10,000 m below the Earth's surface
01:40 contains 50,000 times more energy
01:43 than all the world's oil and natural gas resources.
01:47 But how can we harness this energy?
01:51 The most common way of capturing geothermal energy
01:58 is to tap into the naturally occurring
02:01 hydrothermal convection system.
02:04 This is where cooler water
02:06 that seeps into the Earth's crust
02:08 is heated up and rises to the surface.
02:11 Once this heated water is forced to the surface,
02:14 it's relatively simple to capture.
02:16 So while you're soaking up the benefits of the hot spring,
02:20 just underneath you,
02:22 a pipe can be sending hot water
02:24 directly to a heat exchanger in your home.
02:27 At a geothermal power plant,
02:29 they drill their own holes into rock to capture steam.
02:33 There are a few different methods that power plants use,
02:36 but they all pull hot water and steam from the ground.
02:40 When they're done with it,
02:41 they send the warm water back to where it came from
02:44 to help prolong the heat source's life.
02:47 There is one downside to this, however.
02:50 Dry rock geothermal power stations
02:52 inject high-pressure water into deep wells
02:56 to extract heat from the fractured rock
02:58 near the Earth's core.
03:00 This process is very similar to fracking,
03:03 and with that comes the potential of earthquakes.
03:06 So understanding these risks is crucial.
03:10 But the consistent energy output of geothermal plants
03:13 makes them more reliable than coal or nuclear.
03:17 They're even more dependable than solar and wind,
03:20 because they don't have to wait for the right conditions
03:22 to generate energy.
03:24 Iceland is leading the world in harnessing geothermal energy.
03:28 Not that long ago,
03:30 they were one of Europe's poorest countries,
03:32 relying on peat and imported coal for energy.
03:36 Now it's a country with a high standard of living,
03:38 where practically all stationary power
03:41 is derived from renewable resources.
03:44 In 2014, geothermal accounted for 66%
03:49 of Iceland's primary energy use.
03:52 Reykjavik, Iceland's capital,
03:54 uses thermal energy harvested from hot springs
03:57 to melt their snow.
03:58 Hot water is pumped through tubes
04:00 under many of the sidewalks there.
04:03 It's like in-floor heating, but in the great outdoors.
04:07 Think about having access to so much energy.
04:10 You could heat all the roads and sidewalks
04:12 in the Northern Hemisphere.
04:14 The number of winter car accidents
04:16 and slip and fall accidents would dramatically decrease.
04:21 We could also do this with soil
04:23 and grow seasonal crops year-round,
04:25 locally in toasty geothermal greenhouses.
04:29 Delicious, unlimited tropical fruit in winter climates.
04:33 No more importing,
04:34 because there's nothing like a fresh Swedish banana.
04:39 If you're a seafood lover,
04:40 how about a geothermal heated fish farm?
04:44 You could have fresh salmon or tilapia all year round.
04:47 So why is geothermal power not our primary source for energy?
04:53 Well, for starters, it's costly.
04:56 To drill just a single well at a depth of 4 km
05:00 costs about 5 million U.S. dollars.
05:03 If the heat happens to be further down,
05:05 say 10 km,
05:07 then the drilling costs skyrockets to $20 million per well.
05:12 Granted, as drilling technology continues to progress,
05:16 these prices could drop by millions.
05:18 And price-wise, it's not much better for the average homeowner.
05:22 Home pump systems can be as much as $30,000 initially,
05:26 but would bring your energy bills down by 30 to 40 percent,
05:30 and pay for itself within 5 to 10 years.
05:34 Geothermal energy would also reduce our carbon emissions,
05:37 which could significantly impact our changing climate.
05:41 Unfortunately, though,
05:43 it would take decades for Earth to stop warming
05:45 because of the damage we've already done.
05:48 With climate change being such a hot topic,
05:51 it's inspiring to see countries like Iceland running so clean and green.
05:57 Utilizing elements of geothermal, wind, and solar
06:01 should be commonplace,
06:02 because there's no longer any denying
06:05 the negative environmental impact of fossil fuels.
06:09 So could we completely stop burning fossil fuels around the world?
06:15 Well, that's a story for another WHAT IF.
06:19 (upbeat music)
06:22 (upbeat music)