字幕表 動画を再生する 英語字幕をプリント Energy is the basis for everything. It's the basis for our lives. We can't survive without energy. What is this thing we talk about, energy, and why does it matter so much? It matters because it defines who we are. It matters because defines where we work, how we get there, what we invent. It matters because tracks directly with prosperity and human progress. Energy, simply speaking, is the ability to do work. Energy has been the enabler for modern civilization. In fact how we use energy, and how much energy we use is the defining element of modern civilization. In United States, we consume 100 quadrillion British thermal units of energy every year. One BTU is about the energy content of a kitchen match. In the United States, we use 100 quadrillion BTUs or 100 quadrillion kitchen matches of energy a year which is the same as 100 billion million kitchen matches. This is 16 billion barrels of oil equivalent energy consumed in the United States every year and we are 20% of global energy consumption. You can start to get a sense of the scale of this. 37% of it comes from petroleum or oil. 25% comes from natural gas and 21% comes from coal. The remainder is split almost equally between nuclear power and renewable energy. So we get 9% of our power from a nuclear energy and we get about 8% overall from renewables. The largest as hydropower but also wind, solar, geothermal, biomass are some other key renewable energy sources. Historically, energy consumption the U.S. has increased in lockstep with economic growth in roughly the same percentages. U.S energy use has been heading upward inexorably since the country's founding, and it's always been a challenge to find the right way to supply that energy in a way that's economically sound, that is not environmentally destructive, and destructive for human health in that is also compatible with national security needs. Wood was our first intensive use of energy. We used it to cook, we used it to heat, and once we had harnessed the steam engine, we used it to power or run machinery. The key thing that happened was the industrial revolution. In order to have this industrial revolution we had to fire it up was something that burned much more efficiently than wood. Coal is the transformative fuel. It allows for industrial activity, it allows for factories that are steady-state production. You don't have to wait for water, you don't want for wind. It was cleaner and it produced more heat and more temperature so we could use it to melt metals, for example. And it became the dominant fuel source for about six decades. With stunning quickness that idea of king coal's dominance is undermined and destroyed by the discovery of vast new sources of oil. Out of World War II and the development of the Manhattan Project, we saw the rise of nuclear power which made significant inroads into energy consumption. But it was at that stage and this is probably around 50s that you get the first real questions of environment creeping in. and particularly local environment in trying to clean up air quality in the cities. Then as we move into the late 90s and the early 2000s we begin to get the climate change pressure and that starts a big push towards lower carbon, and particularly renewable sources of energy. Now we start to see evidence that natural gas of all sorts that we didn't even know we could produce is on the verge of making the same kind of motion in the energy mix that oil made in the early 20th century in pushing oil and coal back. People have not had to care about energy per se. And, in fact, people don't care about energy they care about services that energy provides and it gives us a lot of good things that we think as being pretty central to our quality of life. You use energy every day to run your household. You wake up in the morning, get your kids cleaned up. You know you transport them to school there's an energy use there. You transport yourself to work. Wherever your working there's energy consumption all day long to run the building, to run the computer systems. You use energy to get back home again. You use energy to cook dinner at night. I mean that's kind of a typical daily pattern of use. Production of virtually everything takes energy or things that can be used to produce energy. You know you go to a modern farm and see all the machinery. The grain has to be transported by energy-powered trucks to processors, and it has to be transported to your store, and so basically at every step of the food production chain, energy is involved. We use energy at every step of the day. We use it in great abundance. We use great quantities of that energy to achieve all the different things were trying to achieve yet don't know where comes from, we don't know the environmental impacts, we don't know the real costs. So there's a remarkable disconnect between how we use, what we use, why we use it, and where it actually comes from. We believe electricity is invisible that means i flick my switch and I don't believe in my mind that there's a fuel behind that. I'm convinced some people think that electricity just comes out of the wall, that nothing goes into it, and most electricity in the United States right now is generated by coal. On the one hand that people, yes, they want really cheap energy, but on the other hand they're concerned about pollution and things of that nature and so they want people to consume less of it. There's this fundamental attention, you know, bordering on schizophrenia between believing that energy is sort of somebody's birthright and that we have a right to have cheap energy and on the other hand being anxious about the consequences of consuming too much of it. We've been faced with challenges that should have forced us to make changes in the way we deal with energy for decades, but we still have big problems. We're vulnerable to ever-increasing oil prices around the world and we continue to pump enormous amounts of greenhouse gases into the atmosphere in ways that will come back to bite us in the long run. We need to have a rational conversation energy because the stakes are so high. We get so much good out of energy if the manage it the right way, and we get so much bad out of energy if we mismanage it. The bad stuff being pollution or depletion of resources or national security vulnerabilities. The good stuff being prosperity, health, wealth, peace, that kind of thing. So the stakes are very high and if we manage this in a rational way the chances of us taking the right path towards a better outcome is much more assured.