Fuel Efficiency Tips

democrates

With the price of fuel and the environmental cost of fuel emissions, this may we worth thinking about:

From http://www.nutramed.com/environment/carsepa.htm

Catalytic converters, the part of car exhaust systems designed to break down nitrogen gases are actually forming nitrous oxide - 300 times more potent than carbon dioxide as a greenhouse gas. Nitrous oxide makes up about 7.2 percent of the gases cited in global warming, the USA EPA said in a study published spring 1998. Vehicles fitted with catalytic converters produced nearly half of that nitrous oxide. Nitrous oxide also comes from nitrogen-based fertilizer and manure from farm animals.

Here's a few tips on fuel economy following a quick google:

• Use public transport, chill out and have a beer!
• Walk or Cycle, it's better for your health and pocket
• Cut out unnecessary journeys, EG do the weeks shopping in one trip
• Car-pool and split the costs, you can also save on parking fees
• Don't bother with super-plus unleaded, use regular
• Keep your tyre pressures right, soft tyres cost fuel as well as dangerous
• Keep your engine serviced, don't just wait for the nct or until something's wrong, a gammy engine can waste fuel
• Choose a route so you can drive at a constant speed rather than stop-start traffic, so long as the distance isn't much greater
• Don't carry unnecessary heavy items in the car, you're paying to move that weight
• Don't use air-conditioning unless you really need to, it eats electricity and more fuel is needed to generate that
• Keep the windows up if possible, but no more than half way down. An open window at speed creates huge drag
• Don't do a Mondello from the lights, or race to a red light and jam on. Making the car accelerate quickly eats fuel, and jamming on means you've spent more fuel than you needed to getting there. The challenge on a journey is not to have to stop and start.
  • Anticipate if the lights are red ahead, slow down so that by the time you get there they'll be green and you just saunter through without having to stop. Same with traffic that has slowed and is going to speed up again.
  • Don't tailgate the car in front, that means they control your accelerating and decelerating, instead stay well back and choose your optimum speed
  • If you're slowing down gradually or going down a gentle hill, put your foot on the clutch and let your revs drop down to idling speed, that uses a lot less fuel than driving that distance at 2-3krpm. **Note that this may be contrary to the rules of the road, you are meant to be in the right gear for your speed so you can accelerate or decelerate in response to a potential hazard, but in my experience on dual carriageways when there are few if any cars around, no cyclists, pedestrians, or junctions, and I'm well within the speed limit it's been a minimal risk.

There's another point I'm not sure on: Is it better to keep your fuel tank
A) Between empty and half full
Between empty and full
C) Between half full and full
The first option makes sense to me as you're carrying less weight around, and don't let sediment build up in your tank, but some people say the last option is more efficient for some reason. Anyone know the facts on this?

Anyone any other ideas on this?

Wibbs

Some good points there. Agreed on the normal unleaded v super. Most cars won't see a difference and adjust the ECU to compensate. Air con is another one. Eats the juice and drops your engine power output a lot. Same with windows rolled down. Very bad for fuel economy. Correct tyre pressure makes a surprisingly big difference. Keeping your car properly serviced also makes a difference. A clogged air filter will make the car much less efficient.

As for accelerating quickly, I've seen data which suggests that getting your car up to it's optimum efficient engine speed quickly(within reason) actually saves fuel. Dawdling up to 55 Mph is more wasteful apparently. This would only apply for the most part out of town anyway.

Coasting to a stop is another good plan. It does contravene the letter of the rules of the road, but since the rules of the road were written up at a time when car's brakes were less efficient than today and using your gears to slow you down was a useful tactic, I wouldn't be too concerned. In fact, I'd rather coast into the back of someone(or something) than drive into them. It always struck me as stupid to go down the gears when slowing down to a traffic light as if your foot slips off the clutch... bang.

As for your fuel tank question. IMHO the idea that it's good to have a full fuel tank comes from the fact that most fuel guages aren't linear in their indication. They are slower to drop from full when compared to nearly empty, so people naturally percieve the car as using less fuel with a full tank. The engine gets supplied with exactly the same amount of fuel regardless of the fullness of the tank(notwithstanding the extra weight of the fuel itself).

All I'd add would be to get a fuel efficient car in the first place. Under 2 ltrs for a start. Some of the more "sporty" cars are in fact more fuel efficient than more "green" percieved cars. Basically, to get more power, the engine must be bigger or more efficient for the same size. This also translates into better fuel economy and less emissions as a side benefit(if you don't drive like a looney of course ) EG I have a standard Honda integra 1.8, one of my friends has the Type R 1.8 looney stripped down racing snake version and if you drive his at the same constant speed, he gets better fuel consumption. Lessens my guilt at buying one myself anyway.