Drive easy
Wired magazine recently came up with several grandiose proposals for fighting climate change — giant skyscraper-sized air cleaners mounted on battleships, continent-sized space umbrellas orbiting the Earth, and so on. More such projects are proposed every year, with no one suggesting where the technology or money will come from.
But there is a simpler way to fight climate change, one that would extend our oil supply, reduce traffic deaths, and save you money all at once. It’s simple: drive slower.
While there are always a few speeders — around here there are “boy racers” who take hairpin country roads at dangerous speeds — most of us don’t need to go more than 80 kilometers an hour even on the motorway, and 60-80 on country roads. Driving in this window puts most cars at maximum efficiency, and uses the least amount of fuel.
To spread this message, U.S. farmer Fulton Hanson promotes an international “Drive Easy” campaign and a web site, http://greenslowmovingvehicle.squarespace.com/. In-between being a grandpa and taking care of his land, Hanson has been an ecological activist for four decades, doing everything from protecting local wildlife to working for political campaigns to investing in fuel-cell technology.
His most recent project, however, is something everyone can do easily, almost every day, with immediate financial benefit.
Hanson’s plan has been endorsed by a number of international ecological organizations, including the Orion Grassroots Network, Congregations Caring for Creation, Global Warming 101, Alliance for Sustainability and the Sierra Club.
As Hanson says, “It’s not the only answer to climate chaos and the oil crisis, of course, but it’s a first step that everyone can do — now, easily, with no new technology or training. We already have the grand solutions; we need to get more people to take those first steps.”
In a similar vein, a recent article in the online Low-Tech Magazine proposes that the best way to cut our fuel costs would be to cut our speed. We tend to overlook this simple means, author Kris De Dekcer said, because:
Engineers treat velocity as a non-variable, while in fact it is the most powerful factor to save a really huge amount of energy - with just one stroke, at minimal cost, and without the need for new technology. Lower speeds combined with more energy efficient engines, better aerodynamics and lighter materials could make fuel savings even larger.
Air resistance (drag) increases with the square of speed, and therefore the power needed to push an object through air increases with the cube of the velocity (see the formula here). If a car cruising on the highway at 80 km/h requires 30 kilowatts to overcome air drag, that same car will require 240 kilowatts at a speed of 160 km/h.
Thus, a vehicle needs 8 times the engine power to reach twice the speed. In principle, this means that fuel consumption will increase fourfold (not eightfold, because the faster vehicle exerts the power only over half the time).
Over a distance of 1,000 kilometres, the slow car would consume 375 kilowatt-hours (12.5 hours multiplied by 30 kilowatts) and the fast car would consume 1,500 kilowatt-hours (6.25 hours multiplied by 240 kilowatts).
However, this extra fuel consumption can be diminished or even negated by, most importantly, more fuel efficient engines, lighter vehicles materials and better aerodynamics. Even though today’s cars are faster than those from decades ago, they consume a similar amount of fuel. This is the reason why almost everybody is talking about energy efficiency and aerodynamics, and not about speed.
But if you lower the speed, fuel consumption is decreased by the full 75 percent. More efficient technology can not change that – unless in a positive way. If you combine a lower speed with more fuel efficient engines and better aerodynamics, fuel savings can become much larger than 75 percent.
Of course, you might say, such actions are a drop in an ocean. But change comes from thousands of such small actions. It was generally big-budget extravaganzas that got us into this mess, and it is the modest, the tiny and the slow that will get us out.
