首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
High in the Mojave desert, 130 miles northeast of Los Angeles, lies a vast field of mirrors. Crisscrossing rows of glass and met
High in the Mojave desert, 130 miles northeast of Los Angeles, lies a vast field of mirrors. Crisscrossing rows of glass and met
admin
2023-01-16
47
问题
High in the Mojave desert, 130 miles northeast of Los Angeles, lies a vast field of mirrors. Crisscrossing rows of glass and metal, glinting in the sunlight, cover a full square mile of dirt. It is a fully operational array of power plants churning out an average of 180 megawatts of electricity.
Most people think of solar power as a flat panel on every rooftop. But photovoltaic panels have limitations. They work fine when the sun is strong, but when the clouds roll in you’d better have batteries to run the TV and dishwasher. And even on the sunniest days the panels are not very well suited for cities, where roof space is limited.
For decades, engineers have been working on ways to catch the sun over a broad area concentrating it and using it to produce electricity on the same scale as centralized coal, hydro or nuclear power plants—hundreds of megawatts at a time. Several pilot plants have been operating in California, some for decades, but so far they have not had enough volume to force costs down to competitive levels.
Some countries are expected to go with much larger plants capable of generating more than 100 megawatts each. If some of the projects are completed, costs could come down from the current 15 cents a kilowatt-hour for the Mojave plant to 8 cents per kwh in the next 8 to 10 years. That would go a long way toward closing the gap with gas and oil, which now cost as little as 4 cents per kwh.
The Mojave plant is one of the world’s first commercial solar power plants, with five solar Electric Generating Systems (SEGS) supplying electricity to southern California. The basic component of a SEGS plant is a row of mirrors that reflect sunlight onto a pipe filled with oil. The oil heats up and is used to produce steam, which turns an electrical turbine. Assemble a few dozen rows of these trough-mirrors, and you have got capacity to generate 30 megawatts of power, enough for half a small town. The problem with trough technology is that the oil loses its heat too quickly. When the sun goes down, so does the power.
A Solar Tres design uses molten salt instead of oil. Since salt holds more heat longer than oil, it can drive turbine through the night. Concentric rings of mirrors direct sunlight to a tank of molten salt. When the stuff is hot enough, some goes straight to a generator to produce steam, while the rest is stored for use at night. The 15-megawatt Solar Tres plant would be the first long-term commercial power production project. Since the electricity is expected to be costly close to 20 cents per kwh, the Spanish government plans to subsidize the plant.
The next big thing—Dish systems—is already in the works. The building block of such a plant is a parabolic mirror, shaped like a satellite dish, that reflects sunlight onto a small generator suspended in front. The heat drives a turbine. Theoretically a dish configuration would produce more energy per acre than other solar concentrating plants, that is, if engineers could figure out a good way of linking many dishes together.
What is the present cost for the Mojave plant?
选项
答案
15 cents a kilowatt-hour.
解析
文章第四段提到,如果其中一些项目得以完成,未来8—10年,莫哈维电厂的成本可能会从目前的15美分每千瓦时降至8美分每千瓦时。因此,莫哈维电厂目前的成本是15美分每千瓦时。由此可知本题答案。
转载请注明原文地址:https://kaotiyun.com/show/HWSD777K
本试题收录于:
B类竞赛(英语专业本科专科)题库大学生英语竞赛(NECCS)分类
0
B类竞赛(英语专业本科专科)
大学生英语竞赛(NECCS)
相关试题推荐
A)Nodisciplineshaveseizedonprofessionalismwithasmuchenthusiasmasthehumanities.Youcan,MrMenandpointsout,beca
Whendopeopledecidewhetherornottheywanttobecomefriends?Duringtheirfirstfourminutestogether,accordingtoabook
Publicrelationsisabroadsetofplannedcommunicationsaboutthecompany,includingpublicityreleases,designedtopromoteg
TheFrencharejustlyproudoftheirrevolutionarytradition.【B16】_____________Saywhatyouwillabouttheoutcomes,buttheori
Theonlypopularthoughtaboutbeautytoday,theonethathasthewidestcurrencyintheworld,istheideathatbeautyliesin
[A]Westworidchallengesustoconsiderthedifferencebetweenbeinghumanandbeingarobot.Fromthebeginningofthisnews
Parentsandstudentsarenowrelyinglessontakingoutloansandmoreongrants,scholarshipsandtheirownincomeandsavings,
Between1852,when【C1】________wasfirstestablishedthatMountEverestwasthehighestmountainonearth,and1953,whenEdmund
Countlessexamplesoneducationfailurereinforcedthecognitionthatthereisfurtherandactualsignificanceofstrengthening
Acollegegraduatejuststartedajobandhefoundsomethingstrange.Oneofhiscolleagueswouldplayhisdigitalcameraorlis
随机试题
在Windows7中,不可以按()的方式排列图标。
斜Y形坡口对接裂纹试验,适用于焊接接头的()抗裂性能试验。
核算产品成本的方法主要有_______、_______和_______三种基本方法。
下述情况中,属于自身调节的是
事件树分析法是按照事故发展的()顺序分析的方法。
保荐机构及保荐代表人应当尽职调查,对发行人申请文件、信息披露资料进行审慎核查,向中国证监会、证券交易所出具保荐意见,并对相关文件的()负连带责任。
实务中衡量投资组合风险最常用的指标是()。
导游:旅行社:行程
A.I’mnotsoconcernedabouthowit’sequipped.B.Idon’tthinkso.C.Itdoesn’tlooklikewedo.RentalCarAgent:Hi.Ho
非齐次线性方程组Ax=b中未知量个数为n,方程个数为m,系数矩阵的秩为r,则().
最新回复
(
0
)