首页
登录
职称英语
High in the Mojave desert, 130 miles northeast of Los Angeles, lies a vast fi
High in the Mojave desert, 130 miles northeast of Los Angeles, lies a vast fi
游客
2024-08-09
23
管理
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.
Questions 66 ~ 70
Answer the following questions with the information given in the passage. [br] What is the disadvantage of the Mojave plant compared with Solar Tres design?
选项
答案
The oil loses its heat too quickly.
解析
文章第五段提到,莫哈维电厂槽式技术的问题是油散热太快。由此可知本题答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3712828.html
相关试题推荐
IfyouflyovertheNazcaDesertalongthesoutherncoastofPeru,youwill
IfyouflyovertheNazcaDesertalongthesoutherncoastofPeru,youwill
IntheU.S.,thelargestcityalongthePacificCoastis______.A、LosAngeles
Inthedesert,severewindandsandstormsoftenforcemybusinesstoclosedown
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavastfi
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavastfi
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavas
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavas
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavas
HighintheMojavedesert,130milesnortheastofLosAngeles,liesavas
随机试题
SevereandincreasingnumerouscriticsarepointingtodeficienciesintheBriti
[audioFiles]2021m5x/audio_ve01005j_ezflisteningxa_0080_202105[/audioFiles]
当代马克思主义新闻观的核心是()A.坚持党性原则 B.坚持正确舆论导向 C.
对室性心动过速描述错误的是A.QRS波增宽 B.可出现融合波 C.左后分支室
作为教师道德主体一分子的教师个人,他的主体地位和主体性并不是由教师个人来确定的,
血栓闭塞性脉管炎营养障碍期最主要的临床表现是A.肢端发黑、干性坏疽 B.间歇性
天柱穴所属的经脉是( )。A.足少阳胆经 B.手少阳三焦经 C.手太阳小肠
一住店客人未付房钱即想离开旅馆去车站。旅馆服务员揪住他不让走,并打报警电话。客人
下列有关注册会计师在对进一步审计程序设计时采取的总体审计方案的说法中,正确的是(
诊断甲亢的首选实验室检查( )。A.FT3?、FT4 B.TT3?、TT4
最新回复
(
0
)