[Coda]

Yes, it CAN save energy to have clocks set forward an hour during the summer, in SOME parts of the US. I specifically SAID this was true, although I continue to assert that it's less of an impact now than it was when the policy was implemented, and in the warmer latitudes and in agricultural areas it has substantially less impact.

My point is that it DOESN'T save energy to set them BACK in the winter. Creating arbitrary schedule shifts causes a lot of damage in terms of life, health, money*, and psychology, and there is negligible benefit to doing so in the latitudes that the US spans except for in Alaska.

Supporting my point: The US has been expanding the range of DST since the policy was introduced. Originally, DST started in mid-spring and ended in early fall. Now DST starts BEFORE THE BEGINNING OF SPRING and runs through mid-fall. Russia did a three-year trial of year-round DST without shifting back and the only complaint was that it got too dark in the morning in the northern parts of the country, but since that comprises a large and very vocal segment of Russia's population due to it being farther north than the US, the complaints forced the government to revert the policy despite the other benefits.

By the way: You should probably cite that "billions of kilowatts" figure, because there's only been ONE case study done on the matter in the last 30 years, when the state of Indiana adopted DST for the first time in 2006, and they found that energy consumption INCREASED (by about 1%) because while there was less electricity spent on lighting there was more energy spent on heating and cooling (net increase, approximately $3.5 billion dollars). The last study done before that dates back to the 1970s and it showed a small energy savings but a possible increase in traffic fatalities ("possible" because they didn't have enough data to prove that the increase was due to DST or due to unrelated factors).

* From 2005 to 2009, I developed time and attendance systems for small-to-medium-sized businesses. DST shifts are a NIGHTMARE in terms of legal compliance and accounting workload, especially for companies that maintain 24-hour operation, and ESPECIALLY for companies who have employees that don't work fixed schedules. The easiest solution for these companies is to ignore DST entirely for their payroll operations and just accept the fact that paychecks get cut an hour later (according to the clock on the wall) during the summer.