Last week, the Independent Market Monitor for the Electric Reliability Council of Texas (ERCOT) released a report showing that the violent prices fluctuations of June 25 and 26 were not the result of market manipulation, as asserted by earlier reports. Most have greeted this as welcome news, but the finding could spell rocky years ahead with wild swings in electric prices from day to day, which makes it difficult for investors, generators and most importantly customers to plan ahead. To understand why, let’s back up a second and talk about what these findings mean.


If the market isn’t being manipulated, it is at least feeling a little bipolar: one hot summer day with high demand prices are up slightly but everything was working fine. The next day however, a 2 percent uptick in demand combined with an unexpected loss of 1.6 percent sent prices soaring. The peak price on June 25 hit $438/ megawatt hour (MWh), but on June 26 prices maxed out at $3,000/MWh, meanwhile average prices skyrocketed to 640 percent above the average for the 25th.


In a well functioning market these price swings wouldn’t be so dramatic and unpredictable, and those swings point to fundamental problems with the electric markets in Texas. In extreme situations prices and profits may increase enough to support new investment but those extremes are so unpredictable that no power company can plan well for them, much less finance new investments. As Brattle Group says in their report to ERCOT, “reliance on scarcity prices is unlikely to achieve ERCOT’s current reliability objectives.” The solution? Reduce our reliability standards or implement reforms that will reliable electricity over the long term without the need for emergency regulatory intervention.

うまく機能している市場では、価格変動はここまで劇的で予測困難になることはないだろう。そして、この価格変動はテキサス州の電力市場の根本的問題を指し示している。極端な状況では新規投資するに十分な価格と利益になるが、そのような状況を予測することは困難であり、発電会社はそれに応じた計画を立てられず、新規投資にはほとんど結びつかないだろう。ERCOTへの報告書で、Brattle Groupは「欠乏状態価格にたよっても、ERCOTの現時点の予備力目標を達成できそうにない」と述べている。解決策は? 信頼性基準を引き下げるか、あるいは当局の非常事態介入の必要なく長期的に供給力を確保する改革を行うかである。


The reason for these swings is pretty simple, and outlined in the Brattle Report: the ERCOT supply curve does not efficiently reflect current or upcoming scarcity conditions in the market. The supply curve is dominated by low price resources like wind, efficient natural gas power plants, along with nuclear power and some cheaper coal, all of which come in at or under about $30/MWh. But as the chart shows, when you start getting near the 100 percent peak demand level there’s a sharp “hockey stick” curve upwards in price. This means that when we’re in that high demand territory, a single power plant going offline or an unexpected spike in demand can send electric prices from $30/MWh to $3,000/MWh without warning, like we saw in late June. Other regions have a more gradual supply curve of price increases during scarcity conditions, providing a kind of ‘warning’ to the market that the Brattle Report suggests as part of its suite of recommended market reforms. That gradual curve is important because it allows demand-side resources to help stabilize prices and at the same time it provides potential investors with the kind of predictable certainty that allows them to consider investing in Texas.


[ COLIN MEEHAN- "The Texas Electric Market Isn’t Being Manipulated, It’s Just Built That Way (…And That’s Not A Good Thing)" (2012/07/19) on EDF ]

  • 最終更新:2012-09-09 04:12:14