Chris King and Dan Delurey provide additional analysis for their recent paper, “Energy Efficiency and Demand Response: Twins, Siblings, or Cousins?” Fortnightly, March 2005.
Letters to the Editor
climate are: The Hong Kong and Singapore times being about one-quarter of the European Union average and less than 10 percent of the U.S. average; the Florida time being higher than for Southern California; and, the Southern California time being about one- third of Northern California.
The Atlantic, Northern California and Pacific Northwest times being higher than the U.S. average suggest the influence of terrain. The Florida time being higher than for Southern California suggests the influence of geography.
The Florida and Scotland times being about 20 percent less than Texas and the United Kingdom average, respectively, suggest there are influences other than population density, climate, terrain, and geography. Other influences that may be at work, but are not obvious from Thurston’s chart, include differences in how electric distribution systems are designed. The American system brings primary voltage lines much closer to the customers than does the British system, thereby having more and smaller line transformers and shorter secondary voltage lines. The U.S. also has secondary voltages about half of the British System voltages, thereby being less dangerous.
Additionally, a learning curve causes response times to decrease as interruption frequency increases. And finally, the ability of regulated entities to control the speed of introduction of new technologies is not available to entities operating in a competitive marketplace.
—John S. Ferguson, Richardson, Texas
The Author Responds: Ferguson makes a valid point; SAIDI performance differences can’t be attributed to technology or any other single factor. But the point of this comparison was not necessarily to assert that utilities in other countries have superior technology, but that they have exceeded American outage-performance standards and therefore present examples worth studying more closely. Moreover, the situational differences Ferguson identifies should provide an excuse not for ignoring the experiences of utilities in those countries, but instead for learning the lessons they have to offer.