A few years ago I tested some hypermiling techniques and computed the miles per gallon on a few tanks of gas in my vehicle. The results were quite impressive. I’ve been using some of these methods ever since and with good results.
Hypermiling (www.hypermiling.com) is the deliberate use of fuel saving driving techniques to maximize fuel economy. These techniques can be used in any car. Most of these techniques are safe and actually promote safety and responsible driving.
One method is to accelerate slowly. Higher rpms typically result in increased fuel consumption. Most of the extra horsepower in American cars is used to waste fuel via unnecessarily quick acceleration.
Another hypermiling method is to put the car in neutral when going downhill, coming to a stop, or coasting on level after accelerating. I use this technique religiously and it’s especially satisfying to cruise in neutral for a few miles, attaining high speeds on long hills.
Another trick is to look down the road and anticipate red and green lights. It makes no sense to keep your foot on the gas if you are coming to a red light. Once you start doing this you’ll notice that truck drivers do this all the time, and it’s likely for the same reason. Save your brakes and your fuel, put your car in neutral, and try to keep the car coasting until the light turns green.
Another technique is to keep your highway speed below the speed limit and ideally below 55 mph. Beyond 55 mph wind resistance increases drastically and mpg decreases as well. Typically the best instantaneous mpg for a given car in gear and with the gas pedal down is in it’s highest gear with the speed kept between 50 and 55 mph.
Drafting behind a semi on the highway is also supposed to provide excellent fuel economy. I tried this once or twice and I didn’t feel safe. I also didn’t feel like I was saving any fuel. Unfortunately, my car doesn’t have a meter that displays instantaneous mpg (like the ScanGauge, http://www.scangauge.com), so I couldn’t verify the fuel savings.
Another technique that is supposed to save fuel is putting your vehicle in neutral and turning off the engine of your car. I only tried this once and it scared the heck out of me! When I turn off the engine of my car, I also lose power steering and power brakes. If I could turn off the engine and keep power steering and power brakes, then I might have tried this a second time.
One last hypermiling technique that I don’t quite fully understand is called ‘pulse and glide’. I believe you accelerate a bit above the speed limit so that you can put the car in neutral and coast for a longer distance than you would normally without the acceleration (I could be mistaken, however). There are a few spots on the roads that I normally drive where this technique works pretty well. These locations are all in-town, long, shallow hills with speed limits of roughly 50 mph. If you try and coast the long, shallow hills at the speed limit, you can’t coast far. But if you get your speed up to about 65 mpg at the top of the hill and then put the car in neutral, then you can coast for a much longer distance. Obviously the downside to this technique is that you must exceed the speed limit, which, in the city, will tend to attract speeding tickets.
I measured my fuel economy for two tanks of gas in early summer a few years ago using these techniques and received 42 and 43 mpg per tank, respectively. This is quite good, considering that the new EPA combined mpg rating for the vehicle I drive is 31 mpg! The car I drive is a 5-speed, four-cylinder, and some have reported that it can get 50 mpg when traveling at 50 mph on a flat highway.
I know that the average person could greatly boost the fuel economy of their car using some of these safe techniques. However, I think most people are either too shy to accelerate slowly or drive below the speed limit on the highway, or they are too distracted on the road to anticipate stoplights or coast in neutral. But it can be done.
My siblings call me ‘grandpa’ in the car because of the way I drive. But I’ve never been in an accident while I was driving or received a speeding ticket. I am very aware of the road and of other drivers, and I anticipate what is going to happen ahead. I think these driving techniques make driving more fun too.