Fuel economy, what's possible ? Another living page that will change as we collect data.
Biodiesel has around 118,000 BTU per gallon, Petrol Diesel has around 130,500, heavier Petrol oils have even more energy, and people do add cleaned up used motor oil to the diesel to stretch their fuel, Listers are known to burn straight motor oil, and the information that came with my 6/1 claimed it would burn any grade of diesel, but the light grades were preferred.
Jeff's (point one two five) .125 gallons per KWH was accomplished with a 2500 watt load. If we were to guess at the fuel economy on petrol diesel, it could be .1125 gallons per KWH with a 2500 watt load. Jeff points out that the cetane rating of bio is higher (better), and the lubricating properties are higher, so a 10% gain may not be realized.
As you may know, a diesel runs more efficiently with an 80% load than it does with a 20% load. so if we are loafing along with a 400 watt load using the genset to watch TV, the amount of fuel per KWH will be higher.
Jeff performed another test with a 1.1 KW load using biodiesel. This test produced .169 gallons per KWH. If we adjust this for Petrol diesel, we might expect .152 gallons per KWH.
With this data, you can see how it may be possible to run a small diesel for a good number of hours per day and not go broke if it's off road fuel. A Farmer friend was paying 95 cents a gallon for the stuff. You could run 7x24 at that price.
At this point, you might be wondering exactly why Jeff is running Biodiesel for these tests? You might picture him in an off grid setting, forsaking city life and all that goes with it.
Actually... Jeff lives pretty close in, with neighbors all around. 6000 sq ft lots are typical there. Biodiesel is a big plus in these settings, the smell we associate with diesels is not present! His previous diesel ran at 2600 RPMs, he had it in an insulated enclosure inside the attached garage. His wife Angie is very understanding and supportive, she didn't kill him the day the house filled with smoke. Jeff has a special flu installed to carry the exhaust out of the garage. The Lister is a more pleasant 650 RPMs, and Jeff is in the process of designing a muffler specifically for the 6/1. I think it's about time to add some Jeff pages so you can see his handiwork.
I swapped email with Jeff this AM, April 30, 2003, we talked a little about Biodiesel and Jeff's affection for it. Jeff explained that the area he lives in doesn't have an abundance of wind, or solar. Biodiesel is nothing more than liquid sunshine, and it allows a person to utilize alternative power where other means are not practical. Jeff also thinks watching the engine run is far more interesting than watching Solar Panels do their work. If one considers that biodiesel can also be made from waste products, it makes even better sense to put it to use. Making Bio diesel at home does not take rocket science, setting up a Lister to burn straight veggie matter is also possible, I've heard stories of Coconut Mills being powered by old Listers running straight Coconut oil. My brother was just telling me there's crops that could produce 500 gallons of oil per acre, I think that's amazing, maybe someday we could tell the Middle East we have far less need for their oil?
Jeff has more data coming, stay tuned for some Jeff pages, I have received some great graphs and more fuel data, the graph below was developed using Biodiesel, the ST head, utterpower drive, and the Lister 6/1.
May 1, 2003
Fuel efficiency: Actual tests using the Listeroid 6/1, ST3 head, and the efficient Allmand drive system produced .125 gallons of biodiesel per KWH. We are working on a few simple MODS that could boost this REAL number even higher. Following is a formula from Jeff Maier that will predict 6/1 fuel usage for this setup.
Fuel Usage Per Hour (Gallons/Hour) = (Load in KW) * (0.0918) + .101