字幕列表 影片播放 列印英文字幕 We all know that it takes a lot of fuel to keep our country running, right? Cars, trucks, planes, trains … What if we could develop a homegrown, renewable source for those fuels? Well, good news — we already are! We can create clean, renewable transportation fuels from plants, trees, and a range of other organic materials — in other words, biomass. Okay, so biomass is organic material — from forest thinnings and wastes … from crops grown to produce energy … and from other renewable energy sources like algae — that can all be converted into fuels. Scientists and engineers are finding new ways to make biofuels that can take the place of conventional fuels like gasoline, diesel, and jet fuel. Here’s where biofuels have a great advantage: they can be made from leftovers, or waste products. For example, nonedible biomass sources like wheat straw and corn cobs are often left over from agricultural production … and some can actually be used to create fuel. And in the near future, crops can be grown specifically for energy, like fast-growing trees and grasses. Right now, biorefineries with new technologies are being built to convert biomass into fuel, power, and even bioproducts like plastics, soaps, and cosmetics. And many biofuels can be seamlessly integrated into existing vehicles and fueling systems for diesel, gasoline, and even jet engines. So, how does it work? Essentially, biomass solids are broken down and then refined into biofuels. There are lots of ways to do this. Enzymes can be used to break down biomass into liquid sugars. Then, microbes like yeast ferment those sugars into renewable fuel. Extreme heat can break down biomass, too. When you take oxygen out of the mix, biomass is rapidly broken down into a bio-crude oil that can be refined into biofuels. Add a little bit of oxygen to extreme heat, and biomass solids are converted to a gas. And that gas can be converted into biofuel. As technology develops, researchers at the U.S. Department of Energy and its national laboratories are working to make more biofuels more efficient. Sustainable biomass resources, more effective enzymes, organisms and catalysts, all help to bring down the costs of producing biofuels. The end result is fuel you can use anywhere — or any way that you would use petroleum-based fuel. Homegrown biofuels: clean and renewable … and a big step forward for America’s energy security.