Elon Musk: The Power of Solar Energy

Learn English with Elon Musk. Join him as he delivers a keynote speech at the 10th World Water Forum in Bali, Indonesia. Musk discusses the potential for solving global water issues through advancements in desalination and emphasizes the underestimated power of solar energy. Learn about his vision for a sustainable future and how we can turn any part of the world green.

Hello, everyone.

Well, I must say I’m very impressed with this meeting room. It’s amazing. I feel like I’m in a waterfall. It’s really lovely here, and that was an incredible performance.

So, I must say I’m quite delighted to be here this morning, talking to you and experiencing this wonderful event and everything that Indonesia has to offer. It’s amazing being here in Bali and Indonesia. Hopefully, everyone saw the mangrove forests because those are very impressive. It’s several hundred thousand acres of mangroves that I think have been replanted, if I recall correctly.

There are a lot of great things happening in Indonesia and the rest of the world. Overall, I would say I’m quite sort of optimistic for the future. I think we should never be complacent or entitled, but I do think that if we are not complacent and entitled, the future will actually be great for the world. I think we’re headed to a bright future overall.

With respect to water, I’ve always thought we call Earth “Earth,” but actually, Earth is 70% water by surface area. Technically, I think if aliens came here and a lot of people think aliens have come here because they’re always asking me about aliens, they would name us “Water” because we are 70% water and only 30% land. What that means is the potential for solving any given water issue is extremely good because there is so much water. There’s obviously desalination required at times and the transport of water, but desalination, as I think most people know, has become very inexpensive. So really, the availability of fresh water is simply about energy and transport.

When I talk to even very well-read, very smart people in the United States, they will often think, “Well, the water crisis is unsolvable,” but in fact, it is very solvable, and we are continuing breakthroughs in the efficiency of desalination. I think we’ve got a great water future ahead of us, and I think a great sustainable energy future ahead of us.

As I mentioned, because the cost of desalination has dropped so much, if you’re just talking about water for individual consumption or water in, say, a hydroponics facility… we’re not simply putting it on the ground for crops but actually have some sort of contained facility that minimizes the amount of evaporation. I think you can basically turn any part of the world green, including the entire world.

So it just begs the question of where does the energy come from, and here’s where I think solar energy is very much underestimated in terms of its capability. If you think about what the Earth would be without the sun, the Earth would be a frozen dark ice ball at roughly three degrees above absolute zero. It would be quite unpleasant, very cold and dark, but because of the sun, we are at quite a nice temperature, quite pleasant, roughly 300 degrees above absolute zero. The sun powers almost the entire ecosystem; it is solar-powered.

When you say, “Well, how much land would it take to generate electricity?” There’s a gigawatt per square kilometer of solar radiation that reaches the surface. For every square kilometer, there’s a peak power of roughly a gigawatt, which is comparable to a power station. Now, the sun doesn’t shine all the time, obviously, so when you net all of that out and say, “Well, how much energy per day does one square kilometer yield?” it’s roughly one gigawatt hour per square kilometer per day, which is still a lot.

If you do the rough math to power the United States, which is a heavy user of electricity, it would take less than a 200 kilometer by 200 kilometer solar array to power the entire United States. If you drive through the United States, there are plenty of sections of the United States where there are basically no people. Or another way to think of it is a small section of the Sahara could power all of Europe or the world. I’m not saying you would be so concentrated in the placement of solar power because it’s better to be more distributed, but the sheer magnitude of solar power that is available is often not quite understood. But the math of it is very clear.

I would strongly recommend a sort of solar plus battery combination, or wind plus solar, to solve all of the world’s energy needs by a lot. Something I would encourage everyone in the room to look at, and you touched on that briefly, is that the cost of solar power has dropped dramatically over the years. If you were to look at the cost of solar power five years ago, or 10 years ago, or 20 years ago, it would have seemed cost-prohibitive. But the cost of solar power today is extremely low, and the cost of batteries to store the energy has also dropped dramatically. The cost of battery storage of electricity has dropped by a factor of 10 in the past five years. Many of the studies that were done were done in times past when batteries were very expensive and solar power was very expensive. I would just encourage everyone to basically take another look at the cost of solar and the cost of batteries, and I think you’ll find that you’re pleasantly surprised.

Well, it’s an honor to be here, and thank you very much for listening to my words. I hope you have a fantastic conference. Thank you.