字幕表 動画を再生する 英語字幕をプリント Without substantial change, getting the greenhouse gas emissions down, we are on a path to large increases in the planet's temperature. You hear a lot about the progress in reducing the cost of renewable energy to make electricity. But generating electricity isn't the only contributor to climate change. It accounts for only about 25 percent of all greenhouse gas emissions. With greenhouse gases you have the electricity sector. But you also have manufacturing, transportation, agriculture, buildings, as well as about 10% from other sources. We need innovation going out there and finding inventors across all these different areas and understanding their energy R&D activities to make sure that they have a path from their laboratory to scaling up into very large numbers. For electricity, wind energy and solar energy prices are coming down. So the electricity sector has to either be able to store that energy or have other zero-emission sources to maintain the reliability that we all depend on. Manufacturing Here we're talking about all the stuff we buy: furniture, beds, the cars themselves, all of those things. Just the very process of making cement is CO2 emitting. There's a lot of embedded energy. We'll have to change the way that we do that manufacturing. Transportation Immediately people think about passenger cars. And they are a big part of that. But transportation is quite broad. We've got railroads. We've got ships. We've got planes. And so every one of those has to get to zero emission. Agriculture. This is a category that often people forget about. Cows actually emit quite a bit of methane which is one of the more powerful greenhouse gases. And so, inventions like artificial meat may have to play a role here. Buildings. We need to invent different processes in order to get the energy used in running all these buildings down, way down, to zero. The path to success is going to require innovation across every one of these sectors. So it is quite daunting. During this century we not only need to invent all of these things, we actually need to deploy them at massive, massive scale. But in my experience innovation can do magical things.