At 1:30 p.m. on Thursday, California's total demand for electricity registered 46,396 megawatts. The California Independent System Operator, California's electricity grid manager, was predicting that peak demand would hit 49,105 megawatts, which would be shouting distance from the all-time high of 50,270 registered July 24, 2006. For the second straight day, California ISO issued a "Flex Alert" asking consumers to turn off lights and go easy on the air conditioning. The Associated Press reported that by 4 p.m. California power utilities were likely to start cutting off power to large energy consumers "that previously agreed to be the first to lose power during an emergency."

A couple of points to consider:

First, if you're looking for a compelling rationale for investing in energy efficiency and conservation, rather than in new sources of additional power, you can't do better than this quote from a spokesperson for the Independent System Operator, courtesy of the AP:

"Having those customers come off the grid is just as good as adding power," said Stephanie McCorkle...

Second, while a regional heat wave gets the main blame for spiking electricity consumption, the ISO's alert also observes that "Another factor affecting resources is a low hydroelectricity level throughout the state -- about 1,000 megawatts below normal --resulting from this year's dry winter."

It's generally not a good idea to attempt to connect local weather conditions to global climate change trends, but the juxtaposition of a drought and a heat wave, in terms of their impact on energy consumption, are troubling, not just for California, but for anywhere else on the globe that may end up getting hotter and dryer in future decades. Simultaneously suppressing supply and boosting demand is a recipe for pain. And turning up the air-conditioning when temperatures rise will only make matters worse.

At 1:50 p.m, California's total demand for electricity registered 47,100 megawatts.