Onda de calor sobrecarrega o sistema elétrico


Comentários do Ilumina sobre o artigo abaixo transcrito, publicado no NYTimes (no original em inglês), sobre a situação do sistema elétrico americano.


Tudo isto que está ocorrendo com os sistemas elétricos dos EUA da costa Oeste, passando pelo meio-oeste americano e indo até a costa leste (lá eles são interligados apenas regionalmente e não nacionalmente), é uma repetição do ocorrido de forma dramática em 2003, quando, por conta da onda de calor daquele verão (heat wave), semelhante a esta que agora está ocorrendo por
lá, houve black-outs gravíssimos, sendo o de New York de constar no Guiness Book of Records.

Não sabemosexatamente se tal fato se dá por falta de ‘jogo de cintura’ dos americanos, ou de capacidade de reagir ao inusitado e em aprender a lidar com uma situação inesperada, de urgência, quanto a providências a tomar (pela expressão “inesperada” que utilizamos entenda-se ao ter ocorrido pela primeira vez há tempos atrás, e, como vemos a coisa toda se repetir a cada
ano, ficamos a vontade paratirar esta conclusão).

Também não sabemosse esta situação se deve a eles nos EUA entenderem como “fazer planejamento” apenas ficar analisando como reduzir ao máximo os gastos com os combustíveis fósseis que usam (para aumentar os lucros com
ações negociadas em bolsa de valores).

Já deveriam ter aprendido a lição de que a demanda cresce com o aumento da temperatura, e o sistema de transmissão deve estar adequado a estas
situações possíveis para atender satisfatoriamente ao crescimento do consumo durante o alto verão.


Parece que, pelo artigo do NYT, algumas pessoas
com grau de importância no setor elétrico americano estão começando a atentar para estes aspectos (J. Craig Baker, the senior vice president for regulatory services, said that the heat wave “is stressing the transmission and distribution system considerably,” and that the industry needed to
think seriously about how to reinforce it.)

Não sabemosexatamente qual o papel do ‘NERC’ (National Electric Reliability Council) nesta questão, mas deveria estabelecer normas e critérios de planejamento que adequassem os sistemas elétricos de lá a estas condições de alto consumo (zelando pelo cumprimento do objetivo de seu nome, que é cuidar da confiabilidade).

Tampouco sabemos dizer se o NERC é apenas uma entidade que emite recomendações,
que podem ou não serem seguidas pelas empresas,que têm que responder perante seus acionistas em bolsa caso os lucros anuais se reduzam por conta de aumento dos custos operacionais, etc, etc… (Projecting demand for
electricity can be harder than predicting the stock market, but the North American Electric Reliability Council tries to do so each spring).

Se este for o caso por lá, então teremos todos os anos este tipo de situação se repetindo. E as empresas concessionárias dos EUA torcendo para
que o sistema de transmissão aguente o aumento de demanda sem que aconteçam novos black-outs.

Este ano, por conta de, ao que parece, inovadoras medidas de conservação de energia, o caos de 2.003 não se repetiu, mesmo com os recordes verificados de aumento da demanda por conta da onda de calor. Mas o risco dos colapsos
de 2.003 voltarem a ocorrem, no nossoentender continua alto, enquanto não forem capazes de planejar os sistemas de transmssão para suportarem este aumento previsível de demanda no verão.


Electrical Use Hits New Highs in Much of < />U.S.



By RICHARD PÉREZ-PEÑA and MATTHEW L. WALD


Published: NYT, August 2, 2006


A smothering heat wave shattered records for electricity use across a wide swath of the country yesterday as utilities and government officials called for conservation and braced for even more strain on the power grid today.


Power systems held up well despite worries about overloaded plants, transformers or lines. But utility executives warned that the risk of breakdowns rises steadily as a heat wave wears on, and with today’s temperatures expected to top yesterday’s, with possible record highs along the East Coast, power companies were girding for a huge challenge.


Three independent system operators, agencies that manage regional grids for New York, the mid-Atlantic and the Midwest, set record highs for electricity demand yesterday, breaking records set just two weeks ago. New England was just shy of a record.


Experts say demand is rising faster than the ability to meet it, which over the long run could pose the risk of both local and regional failures.


New York City took extraordinary steps to cut consumption, including turning off the display lights on the Brooklyn Bridge and ordering the city’s jail on Rikers Island to use generators. Some leading businesses raised their thermostats after Mayor Michael R. Bloomberg ordered most city office buildings to do so.


Over all, the power grid east of the Rockies is fairly strong, experts say, in part because of changes made after the biggest blackout in North American history, in August 2003. Independent system operators and the control room engineers who monitor systems at utilities are better trained and better equipped than they were in 2003, and they are in closer touch with one another.


“At this point, everybody is on their toes,” said Stanley L. Johnson, a spokesman for the North American Electric Reliability Council, an industry group in Princeton, N.J.


As the throb of air-conditioners and generators has become the summer’s soundtrack, most striking is how fast the overall demand for power has climbed. In most cases, the system operators surpassed not only previous records, but also the predictions they made in the spring for peak summer demand.


PJM Interconnection, the system operator whose member utilities cover most of the country from the Hudson River to the Chicago area and as far south as North Carolina, oversaw delivery of about 144,000 megawatts at its peak yesterday afternoon — up more than 10,000 megawatts from the record set last summer. PJM said demand growth has been equivalent to adding another Baltimore and its suburbs each year.


The Long Island Power Authority in New York surpassed 5,600 megawatts yesterday for the first time and predicted more than 5,700 today — 10 percent higher than the record set last year. “It’s an extraordinary growth,” said Richard M. Kessel, the chairman. “This is an extraordinary event, electrically.”


The New England and New York system operators said demand could push higher today, but it was expected to drop in the Midwest. At PJM, the concern was that power use would fall in the Ohio Valley and farther west, but climb along the Eastern Seaboard, putting added strain on the major transmission lines connecting the two regions.


“Tomorrow could be tricky, because if there’s significantly higher demand in the East, getting it to the East will really tax the transmission system,” Ray Dotter, a PJM spokesman, said yesterday. “We’ll still be sweating.”


Power demand has climbed much faster than predicted across the country since 2004, raising concerns about whether efforts to build new plants and transmission lines, and encourage conservation, will satisfy the nation’s appetite for electricity.


At American Electric Power, which serves five million people in 11 states, from Virginia to Ohio to Oklahoma, J. Craig Baker, the senior vice president for regulatory services, said that the heat wave “is stressing the transmission and distribution system considerably,” and that the industry needed to think seriously about how to reinforce it.


Projecting demand for electricity can be harder than predicting the stock market, but the North American Electric Reliability Council tries to do so each spring. In 2003 and 2004, actual growth in demand was smaller than anticipated, but last year’s peak demand exceeded projections by 1.7 percent. Because growth last year was so strong, the council predicted an 0.5 percent rise this year, a number that was clearly too small.


Jim Smith, a spokesman for the New York Independent System Operator, which oversees the state’s power markets and distribution, said: “There are more people, more houses, those houses are bigger, there are more electronics in those houses, and they have bigger air-conditioning units. Computers, plasma televisions, video games, BlackBerrys, iPods — every new gadget you can think of has to be plugged in somewhere.”



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