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the great race中学生英语演讲
last night, when i was surfing on the net,i was attracted by a word:
hydrogen economy. i didn't know what it meant, and maybe most of you didn't, either. so i went on reading and finally got it. and today, i feel so lucky to tell you something about it. and i am going to divide my speech into 4 parts.
let's begin our first part.
science or science fiction?
i used to read a lot of science fiction. the future of energy and transportation were subjects close to my heart. the limitless power of cold fusion. the wonder of matter-antimatter reactors. the challenge of dilithium crystals and warp drive. i almost believed it. i wanted to believe it. but as it turns out, the future of energy is and always hasbeen all around us. it is as natural as wind, sunlight and water. science overtakes science fiction and gives us… hydrogen! i admit that it is terribly anticlimactic. but then we must realize that this changes everything. especially in environmental protection. but when will the hydrogen economy get here?
powerful motivation
priorities are changing. you once heard about the world's supply of oil running out, which it is. we once worried about the ecological effects of automobile pollution. but now, the battle cry is security. we need energy security and power made right here at home and lots of it. wonderful, abundant, clean, renewable, sustainable power. we need to be about the task of finding alternative fuels and energy sources. in the mean time, we need to wan ourselves from dependence on mid-east oil, use our oil, use our oil more efficiently and, almost as an afterthought, lower levels of pollution from our vehicles.
efficiency and cleanliness, while perhaps being next to godliness, have lately taken a back seat to security. however, research and development efforts are mutually beneficial. the next generation of fuel will be both cleaner and locally made. major auto manufacturers and oil companies have often been seen as part of the problem (we can't buy what they refuse to make). but, from their perspective, they can't sell what we don't want to buy.. to them, it is our penchant for gas-guzzling sports utility vehicles that is dangerous, wasteful and suddenly unpatriotic.
hydrogen sources and supply infrastructure
hydrogen is abundant, but there are supply problems. hydrogen is almost never found in its pure form. it is already combined with other elements to form water or any number of organic compounds. to get pure hydrogen, you have to separate it from something. in the case of water, the process is called electrolysis. in hydrocarbon fuels, it is called reformation.
although hydrogen has been successfully reformed from all major fuels, industrial applications for hydrogen today generally rely on reforming it from natural gas. this technique can at best be a short-term solution if the goal is to be independent from fossil fuels. other sources of hydrogeninclude glucose, sodium borohydride and even bacterial composting. not all of these will make the cut. renewability is a key issue. the money, time and effort to turn gtas filling stations, hydrogen filling stations ismind and budget-boggling.
the other problem is supply infrastructure. the money, time and effort to turn gas filling stations. there is considerable mental energy going into solving these problems, but they will not be so;ved quickly or cheaply. at least i believe.
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