Dr. Joan Bushwell's Chimpanzee Refuge

Daylight Savings Savings?

Sometimes the little things mean a lot. I normally get out of bed around 6:00 AM. In the foothills of the Adirondacks in mid June, this means that the sky has been light for an hour. I like this. For whatever reason, my brain just doesn’t want to fully engage in the morning when it’s dark out. This makes the winter months a drag, but come summer, I’m in heaven. Mind you, I don’t need it to be light at 4:00 AM so I am a big fan of Daylight Savings Time (DST). I love the extra hour of sun in the evening, seeing the final rays disappear well after 9:00 PM.

One of the ideas behind DST was energy savings; the fact that most folks don’t get up that early and can use the extra hour of sunlight at the day’s end. Heck, at this time of year the lights in our house might only be on for an hour through an entire day. I’m not keen about the change-over in spring and fall, but it’s one of those markers of the season that you get to used to. Until somebody screws with them, that is.

In 1986 Congress altered the “Spring ahead” command by a few weeks (from the end of April to the beginning of April). My understanding is that this was at least in part due to the urging of lobbyists representing sporting and outdoor goods manufacturers and the like. The idea was that if people were outside longer sooner, they would be more likely to buy these goods. I found this to be silly at the time, but the change-over points were highly asymmetrical to begin with, so this at least brought them closer together (in my area the original changes occurred about four weeks after the Vernal and Autumnal Equinoxes which, although it makes for two six months periods, does not make for symmetrical sunrise and sunset).

With high oil prices in 2005, Congress decided to “do something” to address our energy needs and extended DST. Well, at least that’s what they said and what the news media reported. It was, of course, little more than shouting in the dark instead of shining the light of rationality on the problem. As part of the Energy Policy Act of 2005 signed by George W. Bush, starting in 2007 DST will be extended a total of four weeks, beginning the second Sunday of March and continuing through the first Sunday of November. The claim was that the extension of evening daylight would save energy. In fact, one of the sponsoring senators claimed that adjusting DST would save an average of 100,000 barrels of oil per day for the extension period. Geez, that’s sounds like a lot of oil, but is it? And for that matter, is it a reasonable claim (I do not know the source of it)?

There has been some research on precisely how much energy might be saved by changing the clocks. Here is a study done in California. The bottom line is that extension of DST into the winter months does little to save energy because of the offsetting need to have lighting in the morning. Extending DST for the entire month of March was projected to save an average of .5% of energy usage for the period. The results will likely be worse for states in more northerly latitudes. To be generous, I am willing to go so far as to use this number for the country at large.

The USA’s current oil consumption is around 20 million barrels per day. Using the senator’s claim of 100,000 barrels per day savings is equivalent to a .5% savings, agreeing with the California study. Although there is dispute about the precise figures, it can be seen that the DST change will do little to alter our energy use. Remember, the .5% savings occurs only during the extension period which in this case is four weeks. This converts to an annualized savings of approximately .04%. Saving four hundredths of one percent is like shaving about 200 feet off of 100 miles. Does any sane person think this will make a serious dent in our energy usage? Well, maybe if you’re a congressman or a non-investigative news reporter.

Here’s an interesting contrast. Suppose we were to increase the fuel efficiency of passenger cars and light trucks by a mere 1 MPG. 40% of our oil is used by this class of vehicle (two thirds of all oil goes to the transportation sector as a whole, so I’m not even figuring in heavy or mass transport efficiency improvements). The fleet average is currently a little over 24 MPG for cars and light trucks combined. A 1 MPG increase is about a 4% reduction in usage, or about 1.6% of total consumption. This represents forty times as much savings as the DST change. Now here’s the real kicker: In the late 1980’s, light trucks made up only 28% of the fleet versus about 50% today (the SUV in its present form didn’t even exist for the most part). The fleet average at that time was approximately 2 MPG higher than it is today. Yep, if we simply went back to populating the roads with personal cars instead of personal trucks and SUVs, we’d save eighty times the projection from the DST change. That, of course, does not include the design efficiency increases from the past 15 years, so the real savings would be higher (i.e., those same types and sizes of vehicles from the late 1980’s would be more efficient using today’s engines).

There might be good reasons to extend DST but let’s not fool ourselves that it’s going to do anything about our energy picture. Sometimes the little things mean a lot. Sometimes they don’t mean squat.