At 6:41 PM, Feburary 26th, 2008, The Electric Reliability Council of Texas (ERCOT) activated a Stage Two emergency response to keep the power grid that supplies most of Texas from failing and triggering rolling blackouts.
The operators balanced the grid by cutting off power to “interruptible” customers. These are customers such as industrial sites that have their own power generators and that pay lower rates in return for being kicked off the grid during emergencies.
Several factors contributed to the emergency. Unusually warm weather caused increased consumption. Two coal plants were offline for scheduled maintenance. The major trigger, however, was an easily foreseeable problem:
Preliminary reports indicate the frequency decline was caused by a combination of events, including a drop in wind-energy production at the same time the evening electricity load was increasing, accompanied by multiple power providers falling below their scheduled energy production. In addition, the drop in wind energy led to some system constraints in moving power from the generation in the north zone to load in the west zone, resulting in limitations of balancing energy availability. The wind production dropped from more than 1700 MW three hours before the event down to 300 MW at the point the emergency procedures were activated.
Let me translate that for you: The wind suddenly stopped blowing. It does that sometimes. The grid couldn’t adapt to the sudden loss of wind-generated electricity and they had to kick people off the grid.
Currently, Texas receives 3% of its electricity from wind, the highest percentage in the nation. A lot of people seriously talk of requiring as a matter of law that we generate up to 30% of our electricity from windpower. If a sudden drop in windpower can destabilize the grid when windpower contributes only 3% of total power, what will our reliability look like when unreliable windpower contributes 10%, 20% or more?
Most people didn’t notice this incident because large numbers of diesel powered backup generators across the state kicked in to take up the slack. In the future, are all electricity consumers down to the individual small businesses and households going to have to buy fossil-fuel backup generators to handle routine outages of power? Even if they do, is it even possible for backup generators to compensate for the loss of 10% or more of the grid’s power?
Electricity is not a luxury. It’s a necessity. It has to be available on demand, when and where it is needed. Weather dependent power sources cannot provide that level of reliability. The idea that we can get a significant percentage of our future electricity needs from windpower is a dangerous delusion.
[Update: FuturePundit, h/t Instapundit, wonders if manufacturers will gravitate to regions like West Texas that have abundant windpower, because windpower will reduce wholesale electricity prices. Given that this incident caused a spike in wholesale prices and led to the cutting off of the kind of customers who pay attention to wholesale electricity prices, I’m going to say windpower will be more likely to drive manufacturers away than to attract them. The cost of lost production or the cost of maintaining backup power supplies will easily wipe out any price advantages that windpower might intermittently provide.]