With the price of gasoline again topping $4 a gallon, one can’t help but wonder what members of the Texas Transportation Commission were thinking recently when they raised the speed limit on a 41-mile stretch of highway between Austin and San Antonio to 85 mph.
Do they know, or care, that vehicles’ fuel efficiency peaks at roughly 60 mph and is reduced dramatically by speeding — roughly 7 percent for every 5 mph over that threshold? Thus a car or truck traveling 85 mph will use nearly one-third more fuel than one going 60.
It would be one thing if lead-footed Texans were the only ones to pay the price for this foolish extravagance, but the rest of us will suffer, too, because it will mean less gas to go around. (And as demand goes up, and supply remains constant or drops, prices will surely rise.) It was for this reason that President Nixon briefly instituted a 55 mph national speed limit during one of the Arab oil embargoes of the early 1970s.
If other states go the way of Texas, we’ll likely be paying $5 for gas, or more, before long. We’ll also likely experience increased numbers of highway fatalities, because motorists who continue driving 65 mph or 70 to conserve gas will undoubtedly be getting in the way of those who want to drive 20 or 30 mph faster.
Politics being what they are, there’s no way a presidential candidate will go near this issue before the election, but afterward, we hope whoever wins moves to bring some sanity back to speed-limit setting.