My very first project in home brew RE was a diesel powered genset.   Fred, a good friend of mine, convinced me that all the grid power I was consuming by heating a room full of exotic reptiles using incandescent lighting could be done for FREE using renewable energy via a diesel powered genset and a moderately sized battery bank. Fred even told me I could run the genset for free using something called biodiesel. At first, I was a little skeptical, but Fred's consistency and a little research on the web convinced me this might be an idea worth trying.

Luckily, with a few phone calls, I found a 1982 Toyota diesel pick-up with a 2.2 L series engine being scheduled to be junked and sold for scrap. I bought the whole truck for $50 and even had it delivered free.

Old diesel powered vehicles like the Toyota truck make good candidates for diesel gensets.

The truck looked a little rough, but surprisingly, the engine ran very well for having over 100,000 miles on it. Fred helped me pull the engine out of the truck and other parts needed to set up the genset. We saved the spin on type fuel filter bracket and water separator, along with all the hoses, radiator and battery cables.

The old fuel filter bracket and water separator were saved for use on the genset.

After all usable parts were taken from the Toyota, I called the junkman to come and pick up the truck body.  I degreased and painted the engine and built a stand out of 1"x1" square tubing, some 1"x2" channel and some flat stock steel. Using the old motor mounts and a fabricated bell housing bracket, I mounted the engine in it's new home. The engine was now ready to be test run to check for any excessive vibration, noise or other problems. We hooked up a battery and run the fuel lines into a two gallon plastic gas can filled with diesel for the initial test. The motor ran flawlessly with no vibrations, no overheating problems, and was surprisingly quiet without any type of exhaust system. I purchased an exhaust pipe and a low cost muffler to quiet the genset and keep my neighbors happy.

The exhaust cost under $25 for some pipe, a "turbo" muffler, and a few clamps.

The negative field alternator which originally came on the Toyota was junked, and a new 60 amp externally regulated Delco was purchased to replace it. I had to fabricate a bracket to hold the Delco, and purchase a new fan belt to drive the alternator. We hooked the genset up to my newly purchased 700 amp hour battery bank, and fired the diesel. Fred, with his handheld multi-meter in hand, checked the amperage and voltage produced by the genset. The alternator produced a constant 40 amps to the battery, giving me a C20 charge rate.

A 100 amp externally regulated alternator replaced the old 60 amp Delco when I upgraded to a 1400 amp hour battery bank.

Using a headlight dimmer switch, I attempted to regulate the amperage by regulating the field wire on the alternator. This idea failed and I decided to purchase a three stage Heart Interface "Incharge" regulator to regulate the charging cycle to the batteries. The alternator was later replaced with a 100 amp Ford alternator when I upgraded my battery to 1400 amp hours. The new alternator is capable of producing a constant 85 amps and has cut my charging time in half.

The Heart Interface "Incharge"  three stage charge regulator used for alternator charged systems.

Still running dinosaur diesel through the genset up to this point, I decided it was time to research the idea of "biodiesel".  After purchasing the "Veggie Van" book, and reading several recipes online about making biodiesel, I thought I would give fuel production a shot. My daughter and I went to a local restaurant and asked the manager if we could get some waste vegetable oil (WVO) from the dumpster out back for an experiment we were trying. He told us to take all we needed and come back whenever we needed more. Using an empty gallon milk jug with the top cut off, I scooped about 15 gallons out of the container and poured it into a plastic 30 gallon drum loaded in the back seat of my car. We took the first 15 gallons home and poured it into a plastic 50 gallon drum which I use for WVO storage, then went back for another 15 gallons.

A plastic 50 gallon drum used to store WVO before processing.

We now had plenty of WVO, all we needed was some methanol and lye and we would be producing our own fuel for the genset. Finding the methanol was fairly easy, a local race shop carries methanol for racing and agreed to sell us what we needed. We purchased two gallons for the initial test. Finding the lye was a another story. After checking with several grocery stores, home improvement stores and the local Wal-mart, we finally found "Red Devil" lye at an Ace Hardware store.

Locating the lye proved to be more difficult than finding methanol.

With all the ingredients in hand, we followed the recipes for making biodiesel to produce our first batch of free fuel. Our first five gallon batch was a complete success, yielding over 4 3/4 gallons of usable fuel. The esters separated like the book said leaving about one inch of glycerin in the bottom of the drum. I let the biodiesel sit for about 24 hours and filtered it before trying the new fuel in the genset. The first test was a 50/50 mix of biodiesel and petro diesel to see if the engine would run without any problems. I also installed an extra inline fuel filter to catch any impurities of the newly processed fuel. The genset ran great on the B50 mix and even sounded a little smoother that it did on petro.  The second tank was 100% biodiesel. I couldn't believe I was running a diesel engine on homemade biodiesel. The exhaust smell reminds me of chicken fried steak and doesn't stink up the back yard like petro does, not to mention the environmental advantages.

Genset house built from 5/8 inch plywood encloses the engine and reduces noise levels considerably.

The final step was to build a plywood enclosure to house the new genset. Using 5/8 plywood and a few 2x4's, I constructed a "house" for the new genset. With a hole cut in the side for the exhaust pipe to exit, and a steel grate for air intake for the radiator on the opposite side, the house was ready. The noise levels were cut almost in half and the visual appearance looked great with a coat of paint which matches the color of my house.

Presently, the only method of charging my battery is the biodiesel genset. I plan on adding some PV and possibly a wind genny to reduce the amount of runtime on the diesel. Using a 50% discharge rate, I can go two to three days without having to fire up the genset, and usually get a 100% charge within 3 to 5 hours using less than 2 1/2 gallons of biodiesel.

The complete cost of building the biopowered genset was under $250.00 including the 100 amp alternator. Of course, this does not include the battery bank, Incharge regulator, Inverter, ect...  I used a rather large diesel engine because it was available to me at an affordable price, but any diesel engine which produces 10+ HP can be used. Biodiesel can be produced for around $.60 per gallon after the initial purchase of material. It still amazes me that my homemade genset and biodiesel produce enough power for me to run several rooms of my house and this computer.

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