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For about a century after the first power station was commissioned in 1882, skilled power engineers used hotter steam, higher pressures, better alloys, more sophisticated design, and higher voltages to double the unit size of the largest generating machines every 6.5 years through five orders of magnitude. Had this continued, around 2064 the largest unit would have produced eight billion kilowatts, or about what everyone used for everything (electricity and all other forms of energy) in the mid-1970s. For obvious reasons, it didn't happen.1 Around 1960 big generating units stopped getting more efficient, and they stopped getting bigger around 1970 at around 1,200 megawatts. This proved to be roughly ten times the economic optimum, because the bigger units proved less reliable. Construction-cost economies of scale disappeared in the 1960s and reversed in the 1970s as gigantic scale brought longer lead times, greater complexity and conflict, less flexibility, and more financial risk. By optimizing for the wrong thingprojected capital cost per kilowatt of generating capacity, rather than observed whole-system cost of electricity delivered to retail customersthe industry nearly destroyed itself. Only a few utilities actually went broke, typically from violating Miss Piggy's Fourth Law"Never try to eat more than you can lift"but scores more had near-death experiences, and their balance sheets will take another decade or two to recover. Worse, by interrupting for a decade the previously steady decline in real electricity prices since 1890, the industry created a political backlash now being played outdespite the resumption of falling real prices in 1983in moves to restructure utilities. This is chiefly as a ruse to shuffle or ignore obligations incurred in the 1960s and 1970s to pay for now uncompetitive, mainly nuclear, stations. To be sure, the original proposals for restructuring, the "big dogs eat first" approach, is hardly being discussed any more. Of the modest number of states that are significantly restructuring their utilities, most of the leaders are preserving such public goods as farsighted R&D and cost-effective efficiency investments. They are continuing to reward utilities for cutting customers' bills rather than for selling more energy, and are thus fostering healthy wholesale competition without sacrificing the much larger potential benefit of helping customers to use electricity productively. Early returns from most restructuring experiments also suggest little interest among most customers in having a whole swarm of vendors make them "an offer they can't understand." With California participation so far around 1% despite a $100-million "public education" campaign, RMI's early characterization of the supposedly tsunami-like trend of "retail wheeling" as "Big noise on stairs, nobody come down" seems prophetic.2 Largely unnoticed, however, there was an epochal shift in the choice of power plants in the more competitive wholesale market. Combined-cycle gas-fired power plants with half the capital cost, two-year lead time, doubled efficiency, and railcar portability promptly grabbed half the utility market for new capacity. The era of ordering new central steam plants ended, at least in the U.S. Even more surprisingly, utilities' planned capacity shifted to units that were ten to twenty times smaller, reapproaching a unit-size distribution last seen in the 1940s. Nonutility generation, having fallen steadily from 60% of the nation's electricity in 1900 to 3% in 1980, rebounded twice as fast, returning to 12% by 1996. It also strongly emphasized hundred- or ten-megawatt rather than thousand-megawatt unit sizes. Even smaller unitsplug-in manufactured products down to the kilowatts rangewere rapidly approaching over the horizon. The electric utility business got into its mess in large part because it was an engineering-and-accounting-dominated business. Now that new, often financially trained actors and increasingly competitive conditions are bringing new disciplinary perspectives to the utility industry it has become painfully obvious that million-kilowatt, billion-dollar, decade-to-build stations incurred costly diseconomies of scale. In a country where 75% of the households don't need more than 1.5 kilowatts of average power and 74% of commercial customers don't need more than 10, a million kilowatts is simply too much in one place, often hundreds of miles from its loads. Unnoticed, because it wasn't clearly shown in the utilities' statistics, the cost of building the gridwhich had dominated utilities' construction budgets for most of the 20th centuryand the cost of running it came to exceed the cost of generating the power for the grid to deliver. The U.S. grid's average delivery cost is about 2.4 cents per kilowatt-hour to the average customer in 1996. In short, people who bought and ran power stations and grids are starting to realize that a five- or six-order-of-magnitude mismatch between production and usage makes no more sense than in, say, the cola-can business. What matters, and what they had overlooked to their peril, was that even cheap power stations, if they were too big and too remote, cost too much when the rest of the whole power system is properly included. In 1998, a new introduction to these scale issues systematically organized more than 500 studies published over the previous two decades, and included some sanitized versions of proprietary findings, to explore what factors determine the right size, how to calculate them, and what the calculations showed. Its findings were explosive. Properly counting approximately 75 documented and measurable diseconomies of scale, not just the few well-known economies of scale, will typically make decentralized ways to make, store, or save electricity around ten times more valuable than conventionally scale-blind comparisons had long shown. This would mean, among other things, that photovoltaics for making solar electricity are cost-effective now in most applications. The scale effects that yielded this finding came in four main categories. The most important came from financial economicsthe risk-assessing discipline that underpins the world's financial markets. For example:
The second-biggest economic benefits that decentralized resources offer typically come from electrical engineering, and relate to the costs, losses, operations, and repair of the power grid. These benefits collectively increase the value of renewables by about a factor of about 23. They include:
1 Hirsch, Richard F 1989: "Technology and Transformation in the American Electric Industry," Cambridge University Press, New York. 2 Lovins, A.B. 1996: "Negawatts: Twelve Transitions, Eight Improvements, and One Distraction," En. Pol. 24(4), April, RMI Publication #U96-11, www.rmi.org.
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