Speed Limits and Fuel Efficiency
There is on particular trip we have been on that we have done twice. Both times with the same vehicle, and towing the same camper. But both trips had extremely different fuel consumption.
The trip I refer to is from the Gold Coast to Borroloola in the Northern Territory (more specifically King Ash Bay). The first time we did the trip we took our time and except for taking-over the odd road-train, we generally stayed well under the speed limit. Probably 90km/h.
The next time we did the trip, we were hammering the speed limit. The Barkly Highway in The Northern Territory has a speed limit of 130km/h.
I will use the section of road between Barkly Homestead and Cape Crawford (Heartbreak Hotel) as my example for the comparison. It is the Tablelands Highway. Mostly a single lane, unfenced road with plenty of Kangaroos and wandering cattle. One thing it doesn’t have … Is petrol stations.
So our little vehicle “Ellen” is a Suzuki Grand Vitara with a little V6 under the bonnet. She has a 60 litre fuel tank. We also carry about 20 litres of fuel in two 10 litre jerry cans.
On our first trip was in 2009 along the Tablelands Highway. This was the trip when we were taking our time. We travelled at 90km/h at cruising speed, but regularly slowed down being cautious when we saw cattle in the side of the road. Several times we had to come to a complete stop to wait for cattle to move off the road.
This section of road is 378km and we we DID NOT have to use the fuel in the Jerrycans to get to Cape Crawford.
In 2011 we did the same trip again. This time we were following another vehicle that wasn’t towing, so we were travelling a lot faster to keep up. I’m pretty sure the speed limit on the Tablelands Highway is 110kmm/h. Rather than cruising at 90km/h like we had done the previous time, we were very regularly crusing above the speed limit. Not only did this make the trip uncomfortable, but also very expensive on fuel.
On this trip we only got just over half way to Cape Crawford before we had to stop and add the fuel from the jerry cans. When we got back on the road we did slow down a bit. We had to to make sure we got to Cape Crawford on the small amount of fuel we had left. A couple of hours later we pulled up at the petrol bowser of the Heartbreak Hotel at Cape Crawford with our low fuel light on.
We had used 80 litres of fuel on this trip. On the exact stretch of road the last time we used less than 60 litres of fuel. Ever since then, we have decided that our maximum speed limit will be 90km/h. It uses heaps less fuel, is a more comfortable ride and has less stress on the engine. We have proven that slowing down saves you money.
We are meant to be taking things easy anyway, taking-in our surroundings and enjoying this beautiful country we live in.
