2. 外语
  3. All Change [A]The basic model of the electricity industry was to send high voltages over long distances to passive customers. Po

All Change [A]The basic model of the electricity industry was to send high voltages over long distances to passive customers. Po

admin2016-03-08  38
问题                                 All Change
[A]The basic model of the electricity industry was to send high voltages over long distances to passive customers. Power stations were big and costly, built next to coal mines, ports, oil refineries or— for hydroelectric generation—reservoirs. Many of these places were a long way from the industrial and population centers that used the power. The companies’ main concern was to supply the juice, and particularly to meet peaks in demand.
[B]That model, though simple and profitable for utilities and generators, was costly for consumers. But it is now changing to a "much more colorful picture" , says Michael Weinhold of Siemens. Not only are renewables playing a far bigger role: thanks to new technology, demand can also be tweaked(进行改进)to match supply, not the other way round. Traditional power stations and grids still play a role in this world, but not a dominant one. They have to compete with new entrants, and with existing participants doing new things.
Flattening the peaks
[C]The most expensive electricity in any power system is that consumed at peak time, so instead of cranking up(启动)a costly and probably dirty power station, the idea is to pay consumers to switch off instead. For someone running a large cooling, heating or pumping system, for example, turning the power off for a short period will not necessarily cause any disruption. But for the grid operator the spare power gained is very useful.
[D]This has been tried before: in France, a heat wave in 2003 hit the cooling systems of nuclear power stations and led to power shortages. In response, big energy consumers agreed to cut their power consumption at peak times, in exchange for generous rebates(部分退款). The Japanese have installed 200,000 home energy-management systems that do something similar on a domestic scale. But new technology takes it to another level, allowing a lot of small power savings from a large number of consumers to be bundled together.
[E]Nest is selling its programmes all over North America, and more recently in Britain, too. Customers of its "Rush Hour Rewards" programme can choose between being given notice a day in advance of a two- to four-hour "event"(meaning their thermostat will be turned down or up automatically)or being told ten minutes ahead of a 30-minute one. This can cut the peak load by as much as 55% .
[F]NRG, America’s biggest independent power company, is also moving into the market. David Crane, its chief executive, admits that some consumers find the idea of saving power "un-American" , but thinks that for companies like his the "mindless pursuit of megawatts" is a dead end. In 2013 NRG bought a demand-response provider, Energy Curtailment Specialists, which controls 2GW of "negawatts".
[G]The big question for demand-response companies is the terms on which they compete with traditional generators, which argue that markets such as PJM are starving the power system of badly needed investment. For example, FirstEnergy, a company in Ohio, suspended modernization plans at a coal-fired plant which failed to win any megawatts in the auction for 2017-2018. Such plants are viable only if utilities are paying top dollars for peak electricity—a cost which is eventually passed on to the consumer. Companies like FirstEnergy hope that the Supreme Court will overturn a ruling by the Federal Energy Regulatory Commission that negawatts be treated like megawatts in capacity auctions. These worries are already spooking the market. EnerNOC, which bundles together small energy savings from many different customers to offer negawatts, has seen its share price fall by half since May.
[H]In any case, the days of the vertically integrated model of energy supply are numbered, observes Dieter Helm. Thanks to abundant solar power, he argues, the energy market increasingly resembles the economics of the Internet, where marginal costs are zero. That "undermines the very idea of wholesale electricity markets". The future model will be much more fragmented. Independent generators, plus new entrants, are already "revolutionizing the way electricity is sold and used" : new technologies will make the 21st-century model even more different. "No wonder many of the energy giants of the past are already in such trouble," he says.
No longer so useful
[I]The combination of distributed and intermittent generation, ever cheaper storage and increasingly intelligent consumption has created a perfect storm for utilities, particularly those in Europe, says Eduard Sala de Vedruna of IHS, a consultancy. They are stuck with the costs of maintaining the grid and meeting peak demand, but without the means to make customers pay for it properly. Their expensively built generating capacity is oversized: spare capacity in Europe this winter is 100GW, or 19% of the constituent countries’ combined peak loads. Much of that is mothballed(检修好存置备用的)and may have to be written off. Yet at the same time new investment is urgently needed to keep the grid reliable, and especially to make sure it can cope with new kinds of power flow—from "prosumers" back to the grid, for example.
[J]To general surprise, demand is declining as power is used more efficiently. Politicians and regulators are unsympathetic, making the utilities pay for electricity generated by other people’s assets, such as rooftop solar, to keep the greens happy. At the same time barriers to entry have collapsed. New energy companies do not need to own lots of infrastructure. Their competitive advantage rests on algorithms(算法), sensors, processing power and good marketing—not usually the strong points of traditional utilities. All the services offered by these new entrants—demand response, supply, storage and energy efficiency—eat into the utilities’ business model.
[K]The problem for the state’s electricity utilities is that they still have to provide a reliable supply when the sun is not shining. But consumers, thanks to "net metering" , may have an electricity bill of zero. That means the utilities’ revenues suffer, and consumers without solar power cross-subsidize those with it. Rows about this are flaring across America. Many utilities are asking regulators to impose a fixed monthly charge on consumers, rather than just let them pay variable tariffs. Since going completely off-grid still involves buying a large amount of expensive storage, the betting is that consumers will be willing to pay a monthly fee so they can fall back on the utilities when they need to.
[L]Consumers, understandably, are resisting such efforts. In Arizona the utilities wanted a $50 fixed monthly charge: the regulator allowed $5. In Wisconsin they asked for $25 and got $ 19. Even these more modest sums may help the utilities a bit. But the bigger threat is that larger consumers(and small ones willing to join forces)can go their own way and combine generation, storage and demand response to run their own energy systems, often called "microgrids". They may maintain a single high-capacity gas or electricity connection to the outside world for safety’s sake, but still run everything downstream from themselves.
[M]Some organizations, such as military bases, may have specific reasons to want to be independent of outside suppliers, but for most of them the main motive is to save money. Places like University of California, San Diego(UCSD)not only save money with their microgrids but advance research as well. A server analyses 84,000 data streams every second. A company called ZBB Energy has installed innovative zinc-bromide batteries: another company is trying out a 28kW supercapacitor(超级电容器)—a storage device far faster and more powerful than any chemical battery.
[N]In one sense, UCSD is not a good customer for the local utility, San Diego Gas & Electric. The microgrid imports only 8% of its power from the utility. But it can help out when demand elsewhere is tight, cutting its own consumption by turning down air-conditioners and other power-thirsty devices and sending the spare electricity to the grid. UCSD is one of scores of such microgrids pioneering new ways of using electricity efficiently and cheaply through better design, data-processing technology and changes in behavior. The IEA reckons that this approach could cut peak demand for power in industrialized countries by 20% . That would be good for both consumers and the planet.
A new technology allows small energy savings from many different customers to be gathered together.
选项
答案D
解析
转载请注明原文地址:https://kaotiyun.com/show/BoL7777K
0

大学英语六级

相关试题推荐
随机试题
最新回复(0)