『Discovery』未来新能源 4集全

Key Points:

• Finding energy is becoming increasingly challenging and requires innovative solutions.
• Fossil fuels, our current primary energy source, are depleting faster than they can be replenished, creating a pressing need for alternatives.
• Renewable energy sources, such as solar, wind, and geothermal, offer potential solutions, yet each comes with its own challenges.
• Learning from nature's efficient energy use can inspire innovative technologies and ways to harness energy.
• The urgency for clean and sustainable energy solutions is critical as we face environmental and resource depletion issues.

Finding energy has never been easy. It's always required a lot of innovation, a lot of expense, a lot of risk. In other words, it takes energy to find energy. And doing that is harder today than it's ever be. Energy is the single most valuable commodity of modern society. It's the engine that makes our civilization go. So it's really no wonder that people are willing to go literally to the ends of the earth in order to find it.

I'm out here in the Gulf of Mexico, 100 miles from land. Just a few decades ago, no one would have believed we'd have to venture this far to find oil. Welcome to the Brunusk s. As an environmental scientist, I know all living things need energy, and we are no exception. The problem is, for the past 150 years, we've been pulling most of our energy out of the ground. Coal, natural gas, and the stuff they're pumping out of the seabed here – oil. They're called fossil fuels. And we're burning through them much faster than the Earth can create them.

So this pipe is going all the way down to the seafloor? That's right. This particular well that we're on is about 20,000 feet from this point down to the bottom of the well. That's incredible. There's nothing deeper than we are. And so it's been quite challenging. This rig is in U.S. waters, but we depend on foreign nations for most of our oil. We’re vulnerable should other countries decide to turn off the tap. As we know all too well, environmental disasters like oil spills can be devastating.

And on top of all of that, burning fossil fuels can lead to severe climate problems. The truth is, our dependence on fossil fuels is a house of cards. Sooner or later, it's going to fall. Whatever your issue may be, whether it's diminishing supply or energy independence, jobs, the deficit, national security, or climate change, one thing's for certain, the way we get our energy is fundamentally changing. I mean, drilling this far offshore and this deep is complete proof of that.

Oil's not going away anytime soon. But if we're to get a handle on our energy challenge, then we have to realize that energy is much more than fossil fuels. Electricity, power lines, and gas pumps – that's how most of us think about energy. But take a look around. Energy is everywhere. The sun bathes us in energy every day. Its heat pushes our atmosphere around, creating wind. Its light makes living things grow. That's energy.

Two-thirds of the Earth's surface is water, constantly in motion. That's energy. The surface of the planet itself moving every day, thrusting up mountains, creating new oceans. Quite simply, energy is motion, and it's all around us. But whatever form it takes, most of it comes from one source: an immense ball of burning gas millions of miles from Earth – the sun. The sun is an energy machine.

Its gravity is constantly crushing hydrogen atoms together at its core, converting them into helium and releasing massive amounts of energy. Energy that eventually reaches the Earth as sunlight. A piece of the sun on the earth. Dr. Michio Kaku is a theoretical physicist who can shed a little light on the process.

Think about this. When you wake up, you have breakfast. The energy of your muscles, the motion of your body, all of it, in some sense, is recycled sunlight. All of this, everything we see, everything we see around us.

The hot dog stand. That's right. That's great. Can I get two, please? How does that work? Well, see, the sun provides, through photosynthesis, energy for plants. The wheat eventually becomes the bun here, and the sun energizes grass, which is eaten by cows, which provides the meat for the hot dog. So we see that energy is constantly changing form from sunlight to grass, to cow, to hot dog, to you and out.

Animals get most of the energy they need by eating. And once upon a time, we did the same. But those days are long gone. Animals use energy much differently than us. First of all, animals use energy for survival, for food. We humans, on the other hand, consume as much energy as we possibly can for entertainment or leisure – for that Sunday drive out into the countryside, for skiing, or whatever.

Since the Industrial Revolution, our energy demands have just skyrocketed. Today, food gives us only a fraction of the energy we need. Think about it like this: The food I ate this morning is allowing me to power this 100-watt light bulb, which, by the way, is not that easy as it sounds because I have to keep pedaling quite fast just for one light bulb.

But if I want to power all the stuff in my life, well, then I'm gonna need not just a hundred watts of energy, but 12,000 watts of energy. That's like having more than 100 people working for me, continually pedaling 24 hours a day, seven days a week, just to keep my lifestyle going. And that's an awful lot of energy. Hence why we are so addicted to fossil fuels.

The problem with fossil fuels is that the planet isn't making them fast enough. We're running out of usable energy in the form of fossil fuels, so we have to find a replacement. All energy comes from the sun. A fabulous amount of energy, but only a tiny fraction of it is usable energy to drive our machines.

So if we can't wait millions of years for Mother Nature to make some more fossil fuels, where does that leave us? What options do we have for powering our world now? I mean, the sun has been shining for four and a half billion years. And for four billion of those years, life on Earth has been soaking it up.

The fuels we use today, like coal and petroleum, are really just dead organisms like plankton that had the sun's energy locked up inside them when they died. Squeezed under layer upon layer of sediment and baked for hundreds of millions of years, they became fossil fuels. That's why fossil fuels are such wonder fuels.

They’re packed with ancient energy from the sun. The best way to see this energy is to put a match to it and release it. You can feel the energy just coming off this, just a little bit of ancient energy balled up from the sun. Enough to propel a 3-ton car for miles. Fossil fuels aren't just powerful; they're concentrated.

So the question is, how do we find a renewable source of energy that works just as well? To do that, scientists are becoming prospectors. And the Nevada desert is a good place to start. We take both out – take both out and engineers. Steve Wilcox is a new energy pioneer.

His job is to find the places where the sun's rays shine most intensely. This one is called a pyroh heliometer. It measures sunlight. He says, "Do you consider yourself like a sun prospector? You're really mapping the whole Earth for how much sunlight falls on it and the intensity of that radiation?"

Yeah, that’s almost the holy grail of solar radiometry. How do we understand where the sun shines, the magnitude of it, and the variability of it? The tube of that will fit right in there. When it comes to gathering solar energy, not all open spaces are created equal.

The sun's rays are more intense in certain places, depending on latitude, cloud cover, and air pollution. And with some idea of where the best solar resource is, they can start narrowing down and looking at many other factors that are involved in ultimately building a solar power plant or even putting solar panels on your house.

So our next step is to line this up. North, south. If Wilcox and other prospectors can identify the places where the sun shines most consistently and intensely, solar panels can go where they’ll do the most good.

These are the two signal cables from the instruments. So what does it mean when it says direct here? It says 900. That means we’re getting 952 watts per meter squared, direct beam coming directly from the sun. Basically, in about that much of ground, you’re getting 950 watts, right?

That seems quite substantial because that's like several light bulbs, right? It is. So that's the amount of power that the sun is putting onto the earth right there, right as we're measuring it. And so the next question is, can we actually get that much energy from the sun? Because that's what's coming down.

That's the potential. Yet 1 square meter can deliver nearly 1000 watts. If you wanted to power a city like Las Vegas, you'd need a piece of land equal to 57 miles square. It sounds like a lot, but that actually might be doable to power the whole world. You'd need an area about as big as New York State, and that’s serious real estate.

It may be more realistic to develop a combination of renewable energy sources. That's where wind comes in. Most of us have seen wind turbines. They catch the wind and convert its energy into electricity. But what might surprise you is that it’s actually the sun that makes the wind blow.

When the sun's rays hit the earth, it warms the air near ground level, which expands and rises. Then cooler, denser air rushes in to fill the empty space. It's this up and over cycle that creates the wind.

But it's one thing to know about how the wind is made, and a completely different thing to know how to turn it into usable power. That's where Oregon meteorologist Bob Baker comes in. You may not need a weatherman to know which way the wind blows, but it helps.

Like Wilcox, Baker is an energy prospector. His job is to figure out where the wind blows hard and consistently, because that’s where you want to put your wind turbines. To do that, he also needs to be a kind of detective.

One of the best indicators that we have is when to form vegetation. The deformation of the trees is very important because the more the tree is deformed, the stronger the wind. And those are the sites we want to go get into first. The ones that have the strongest winds will give us the most energy and will give us the best opportunity to develop.

Over the last decade, wind turbine technology has improved by leaps and bounds. Today, each one can generate enough power for 700 homes. Some predict that one day, wind could power half the world. The potential resource that we have is vast.

Most people really don't understand how strong the winds are or how that energy can be converted into usable energy. Electricity. So there's a tremendous resource here. We're just beginning to tap it. But wind power has the same drawback as solar. It takes up a lot of space.

If we wanted to power the whole world with wind, we'd need to devote nearly 2% of all land on earth to wind farms. Not to mention, we can't always rely on it. When you hit that light switch, you don’t want a sign that says, "Oh, well, the winds aren't blowing today. Oh, no, the sun is overcast. You want electricity now."

And that’s one of the weak links that we have to encounter with renewable forms of technology. There is another powerful form of renewable energy that requires little extra space. In some ways, it’s the most reliable form of all.

When the wind blows over the surface of the ocean, it creates waves. Those waves contain substantial energy we can harness. The moon's gravitational pull, along with the sun's, generates powerful ocean tides. That, too, is energy we can harness.

We’ve been harnessing the power of water for thousands of years, and we're still using it. Hydroelectric power generates 16% of the world's electricity. But as dramatic as this looks, water can never give us as much power as the sun can and the wind can.

We're already running out of good options for rivers to dam. But this isn't the only kind of water power there is. Engineers are already working on new tidal and wave technologies that could one day power millions of homes, workplaces, and factories.

In spite of its limitations, the great thing about water is that it’s usually consistent, more than we can say about wind and solar. But can we find an even more consistent energy source, not by looking up or around us, but by looking down?

Deep inside the Earth, thousands of miles below our feet, at the center of the planet burns an energy dynamo. The Earth’s core reaches temperatures of nearly 10,000 degrees Fahrenheit, about the same as the surface of the sun. But we don’t have to go down that far to tap into the power of the core.

Just two miles down, the Earth's crust is hot enough to boil water. Dig deep enough, and we could harness geothermal energy from any point on the planet. That’s ancient power, formed at the core billions of years ago, when our Earth first took shape.

Geothermal energy is so reliable and consistent; we could get most of our power and heat from inside the Earth. But harnessing this heat isn’t cheap. And today, natural geothermal energy generates less than 1% of worldwide electricity. That’s not a lot. And many wonder if we do start turning to more of nature's energy sources, can we keep living the lifestyles we've grown so used to?

If we’re serious about finding solutions to our energy problems, then we’re going to have to be realistic about the cost. Whatever we do, it’s got to be worth the effort. With fossil fuels, there will come a time sooner or later when the cost of getting that energy is going to be more than what the energy itself is worth.

So whatever alternatives we come up with, we've got to factor in the price we pay to get it. We’ll have to do more than just exploit energy in nature. Instead, we need to study the efficiency with which nature itself uses energy.

Ecologist Charlie Hall is doing just that. Of course, I'm just always focused on the energy. Hall believes the only way any creature or society can survive is if it gets more energy out of its activities than it puts in.

Okay, this is about the right elevation here in the Puerto Rican rainforest. That's easy to measure. The basic hypothesis is what is the relation between energy capture and energy use in the forest? Hall and his team are measuring photosynthesis and respiration levels in these trees to see which ones are the most successful at balancing their energy checkbooks.

If a tree expends more energy surviving in a particular spot than it gets from being there, it will die. The successful tree finds a balance between energy in and energy out. I think it’s very simple. Just as the forest cannot use more energy than it has available from photosynthesis, neither can human civilization use more energy than is available either from the sun or for our temporary joyride on fossil fuels.

Until recently, our energy bottom line was healthy. We were in the black because the energy cost of pulling fossil fuels out of the ground was so much less than the energy payoff. The balance is changing as we speak. We're having to travel further, drill deeper, and pay the price in overseas conflicts and environmental cleanups.

We're paying more than we ever have for energy. But no matter how much it costs, we still want more. We consume as much energy as we possibly can, and as a consequence, we are pushing the boundaries of what the Earth can provide.

One day, we'll reach the Earth's limit on some fossil fuels. Before we reach that point, there are some lessons nature can teach us about energy, lessons that can actually improve our lifestyles. If we care about finding more efficient ways of using energy, nature has a lot to teach us.

Plants and animals have figured out how to get the most out of the energy available to them. They’re models of efficient design. Models that have already changed our world. Moth eyes are designed to suck up every drop of light, which makes them excellent role models for solar panels.

The heavier the vehicle, the worse the fuel efficiency. Tree trunks are heavy and strong to keep the tree upright, while their light branches allow them to flex in the wind. We can design cars the same way, making them strong at specific points to keep us safe, but lightweight everywhere else to improve gas mileage.

When Japanese engineers wanted to make high-speed bullet trains more efficient, they based their design on the shape of a kingfisher's beak, which slices through the air with barely a ripple. Today, the trains travel 10% faster by using 15% less electricity. Nature doesn’t waste a calorie of energy. We can learn from that.

And today we can do more than just maintain our quality of life with the same energy. We can improve it. Today's airplanes burn through massive amounts of fuel every day. More than 2% of all the energy we use. Harvard biomechanics researcher David Lentink may have discovered a way to design planes that fly farther on less fuel.

Birds can change the wing shape to maximize their glide performance. So if you want to fly as efficiently as possible, for every speed and every maneuver, there’s a different wing shape that’s going to do best. And we can look in nature at the masters of morphing wings, and that’s birds. Lentink uses high-speed X-rays to film their morphing wings in real-time so we can slow it down and see what’s actually happening.

So, at a low speed, the wings will be fully extended, while at a very high speed, they need to be swept back, and it really increases performance. I'm trying to better understand if that helps them to improve their efficiency. If a plane's wings could change shape depending on the situation, it could have a dramatic effect on fuel consumption.

Your next 747 is not going to look like a bird. But just understanding how these dramatic changes can improve flight performance of a bird and how they actually are achieved could inspire us to come up with new mechanisms that are affordable, easy to maintain and build, and could work for an aircraft so that we can get to the next generation aircraft that's more efficient.

But aeronautic designers may have an even more important lesson to learn from birds. If we look at how these birds flock together, we can gauge how they use energy as a group. For that, his birds get a workout in a wind tunnel.

I’m interested in how do wings move at higher speeds. The other thing I’m really interested in is how do they interact? So they will fly together in the flock and they’ll go towards each other and away from each other. I’m just really curious how they do that.

How birds fly together can give us real inspiration for how we fly our aircraft. If we could rearrange flight patterns of planes to mimic birds, V-shaped flight formations, experts say we could save 15% of the millions of gallons of jet fuel we use every day.

No matter how much we save by improving fuel consumption, we're still going to need new sources of fuel. One kind of fuel we already know how to make comes from the edible part of plants. For example, we can convert the energy in corn kernels into a fuel called ethanol, which is already part of the gasoline mix we get at the pump.

The problem is we need most of the corn we grow for food. But there's a lot of energy in this green stuff we throw away because we don't know how to get at the energy that's locked away inside. We'd have a lot more options if we could figure that out.

The energy inside plants is locked up in a material that's really tough. Cellulose is designed to be strong enough to hold the plant up, but it also locks away the plant's energy on a cellular level. If you can break that cellulose down, you've hit the mother load of energy.

We may not have figured it out yet, but there are creatures in nature that have mastered the art of turning all that green stuff into energy. They’re the microorganisms that turn our kitchen waste into compost. They’re the agents of rot. And when things rot, they give off energy.

And scientists figure that if microbes can do it, why can’t we? Deep in the tropical rainforest, tiny ants have already figured it out. The energy leaf cutter ants live on comes from leaves.

But they face the same kind of challenge we do in getting at that energy. They need a little help. First, they collect the leaves. A lot of leaves. One colony can harvest up to 90,000 leaves in a year. These leaf cutters are really voracious.

In wet weight, that’s about 4 tons worth of material. Just for comparison, that would be roughly about two pickup trucks worth of material. But the ants don’t eat the leaves right away. They turn them over to a fungus, and the fungus turns the leaves into sugar – energy for the ants.

Gart soon at the University of Wisconsin is trying to figure out how the fungus does it. He knows it must have something to do with microbes that turn the leaves into ant food. And why do we care? Because that sugar can be easily transformed into fuel.

We can use ethanol, for example. So all we need to do now is to work out how the microbes do it. If we can figure out the groups of organisms that are working together, we might be able to take that, put that into an industrial setting, and therefore start the process of creation of ethanol.

Swim things is just a matter of time. What it comes down to is how well can you efficiently convert energy from one state to another.

And I think the ants have just figured out a way of doing that more than anything. And once we figure it out, there’s plenty of inedible plant material out there to create massive amounts of ethanol.

You know, around the world, people are using ethanol as part of their clean energy solution. The real challenge, though, is that ethanol really doesn’t pack the same punch that fossil fuels do.

When you burn it like this, the energy just doesn’t seem as intense. I mean, look at that flame. I’m standing quite close to it, and it’s not really that warm even here. This is gasoline. You can almost see the energy as it billows away. Ethanol just not the same.

Ethanol really only has 80% of the energy density that fossil fuel has. That means you just have to use a lot more ethanol to travel the same distance. It’s unlikely that Americans will switch over to pure ethanol anytime soon, even if we do figure out how to make enough of it.

Which leaves us with a troubling question. Can any alternative fuel pack the same punch as fossil fuels? Drew's search for hidden treasures goes from stately pile. That's a nice house. But won't want to dust; Won't want to clean it to scrap pile. All I wanted when I was a kid was to scrap yard.

His heart ruling his hand. I think I must have taken some hallucinogenics last time I looked at the Morris miner. Drew Pritchard is one of Britain’s leading decorative salvage dealers. He scours the country in search of weird and wonderful objects.

That's a manique. There’s nowhere he won’t go and nothing he won’t consider. With help from his wife, Rebecca, he was telling me he drove in a tank. Now, if that's not midlife crisis, what is? And a team of renovators, he transforms thousands of items from junk to gems which then find new homes in houses, bars, restaurants, or even lighting up your street.

Reinventing the way we exploit natural energy resources requires a multi-pronged approach from harnessing the raw power of the elements to learning how other life forms produce, store, and use energy efficiently.

Ethanol is a promising fuel, but can we find others that could deliver a stronger energy punch, something closer to what we get from gasoline? Springall averages about 5 meters per year in the Puerto Rican rainforest. Synthetic biologist Jake Kiesling thinks he may have found the answer through the miracle of genetic engineering.

We are at a point with biology right now where we can tailor-make the biology; we can build genes. We construct metabolic pathways, change the chemistry inside a cell so that it will take a sugar and produce a fuel that behaves identically to the fuels that we're currently putting in our gas tanks.

They can fragment the leader and make it available for microbial. First, he needs the secret ingredient. That’s what he and park ranger Grizel Gonzalez are searching for. There’s a lot of earthworms that can affect the decay rate.

This forest is a treasure trove of energy locked away inside its trees, sturdy cell walls. Months ago, Kiesling's team filled some mesh bags with dead leaves and planted them on the forest floor. They put them there to attract hungry microbes. Here they are, the tubes too. And they have been decomposed for over a year.

Great. These microbes contain potent enzymes potent enough, Kiesling thinks, to help him create a fuel that rivals gasoline. I’m looking for some incredibly powerful enzymes. Here we go.

I think that some of the best enzymes on the planet for degrading biomass might be here in the rainforest in Puerto Rico. Some rainforest microbes can turn a blanket of leaves to compost in less than a year. But that’s nowhere near fast enough for Kiesling.

So it’s back to his lab at the University of California at Berkeley. These enzymes have one basic function – to quickly break down large molecules into small ones so they can be converted into fuel. Fuel for a microbe or fuel for our cars.

All from the stuff we throw away – grass clippings, corn stalks, leftover debris from logging. Once we've identified the best enzymes, then we’ll degrade that biomass and turn it into the sugars that we can use to make biofuels.

But not just any biofuels. We’re talking about fuels as powerful as any fuel available today. Keysling has figured out how to do in one day what it’s taken the earth millions of years to do.

It’s incredibly cool. It’s incredibly cool, right? I mean, we’re taking biomass, which is combustible, but not in a form that you would necessarily want to put in your gas tank and changing it into a chemical form that’s extremely combustible, [with a great deal of energy per pound], and that will fire your engine, allow you to drive down the road. Before we can use it, Kiesling's team needs to work out how to mass produce fuel on an industrial scale.

In the meantime, there may be other ways that nature can help us. What if we could skip the middleman altogether and get our energy straight from the source, just like a plant does?

You may think what you see here is just bubble wrap, but to chemist Nate Lewis, it could be the answer to all our energy problems. Lewis has been working on a new technology based on a very old one, something he calls an artificial leaf.

The idea is to mimic what a plant leaf does. Take energy from sunlight, photosynthesis, and then convert it directly into a clean chemical fuel. A fuel we can store and use in our homes to power everything.

Everybody knows about plants; everybody knows about solar cells, but we’re trying to really combine them. Plants store energy for night, solar cells don't, but they’re much more efficient. If we could have both of those in one device, the best of both worlds, the natural and the man-made, we would really be in great shape.

Lewis's artificial leaf works a lot like the real thing. First, you convert the sun’s energy into chemical energy, then you store it. Plants use sunlight to split water molecules into oxygen and hydrogen. They use the hydrogen to make sugar. Lewis doesn't care about making sugar. He just wants the hydrogen.

You pick up that electrode, this lollipop thing here, that’s a very big sample of silicon. To get it, he starts with a beaker of water, a piece of silicon, the same material used in solar panels, and a lamp that simulates sunlight.

Put it in there and hook it up. Just drop it in here and then clamp it in there. Good. Pointing toward that sunlight. Connect the circuit. Okay, hang on. Except that I have to hit the meter so that it lets electricity flow between those two.

And when I do that, it’s going to make hydrogen bubbles directly from the sunlight. There you go. Wow. When the silicon absorbs the light, it excites electrons which create hydrogen from water.

Kind of like a plant does. The light is essential. No sunlight, no hydrogen. All those bubbles streaming off, that’s hydrogen that’s coming from the water; it’s splitting water. We can use the energy in hydrogen just like we use natural gas.

The problem is it’s not very dense, so you have to collect a lot of it. And that takes a lot of space. Like maybe the roof of your house. That’s where bubble wrap comes in. So what can people do with this? Our vision is that we'll have this in a form that looks like a bubble wrap, and you’ll be able to roll it out on your house, feed in water, feed in sunlight, let the oxygen gas go, and then keep hydrogen gas, which is the fuel that you want to use to run your house, in your car.

But Lewis doesn't stop there. Once you trap the hydrogen in bubble wrap, you can combine it with other gases to create just about any fuel you want. We already have world-class chemical processes that can take that hydrogen with CO2 and make methanol, from which we can make gasoline.

So it really just matters that we make a chemical fuel from the sun. And then humans already know how to convert one into another to make a gas into a liquid or vice versa, depending on what we need as a society.

His work is just beginning. But if Lewis's bubble wrap concept can work on a large scale, it could completely change how we find and use energy from our homes and cars to our cities and entire economies. It’s a big if, not just for Lewis's artificial leaf, but for all the ways we try to tap into the power of the natural world.

The challenges before us are formidable, but it’s not like we really have a choice. The clock is ticking, and the free ride we've been taking on fossil fuels can't last forever.

So can we do it? You bet. Are we gonna do it? I'm cautiously optimistic. I think we're gonna go right to the brink. I think historians looking back at the twenty-first century will say that we came very close to energy chaos.

So we're just gonna have to learn how to live on our planet within the confines of what nature gives us sooner or later, and it might as well be sooner. Whether it's capturing the power of the winds, penetrating the secret lives of plants, or like energy alchemists, transforming sunlight itself into clean, renewable forms of energy we can use day or night.

The answers we seek are all around us. If we can align the technology with the money, with the political will to harness the energy that really is all around us, then we would have taken a giant leap towards solving one of the most intractable problems facing humanity today – how to power our activities on this planet in a clean and sustainable manner. Just think about it. All the energy we could ever want right within our grasp.