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Starting 11 HP Gas Engine On SuperCapacitors

I recently got 49 Amperics supercapacitors to experiment with. One of the projects I am working on is to start various engines around the homestead with supercapacitors. Today I started the 11 HP log splitter using five 400 Farad supercapacitors in series.


Connecting supercapacitors in series increases their voltage but greatly reduces their overall capacitance. The value of the capacitance is actually reduced with every capacitor that you add in series. Most supercapacitors are rated at 2.5 to 2.7 volts and about 300-350 Farad.


Amperics supercapacitors are rated at 3 volts and 400 Farad giving you a double bonus over other supercapacitors. Now you have increased capacity in the first place and you need fewer capacitors to make up a bank. For 12 volt applications you only need 5 of the Amperics supercapacitors to get 15 volts total at 80 Farads.


With the competition you need 6 capacitors rated at 2.5 volts which gives you only 50 Farads.


Amperics supercapacitors have the advantage over the competition in this case.


But can they start an engine?




I soldered 5 of these 400 Farad supercapacitors together in series using 12 gauge wire. I was worried about the size of the tabs because they look small. But I wanted to try these out and see what would happen.


SuperCapacitor bank for starting a small engineSuperCapacitor bank for starting a small engine


I charged the capacitor bank up using a standard automotive battery charger set at 2 amps. Then I took the capacitor bank outside for the real test.


Chris held the camera for me. Chris is a certified automotive mechanic so he did not think this was going to work.


I removed the starter battery from the antique 11 HP log splitter. We have been using an older truck battery which weighs 80 pounds. These batteries usually cost about $150 although you can use a lawn mower battery for starting this engine. The lawn mower battery weighs about 20 pounds. Compare this to the capacitor bank which weighs a mere 13 ounces.


The engine was previously run out of gas so we filled it up before the test. Now the engine had no gas in the system at all. This was going to be a hard start on any given day. I cranked the engine over few a few seconds until the capacitor bank ran down. I am thinking that I may have to double the bank size in order to run this engine. Now it did turn the engine over for a while though.


I took the capacitor bank inside the tiny house on wheels and charged it back up again while Chris ran the engine by starting it on a battery for now to get fuel flowing.


Charging Ultra Capacitors Using Car Battery ChargerCharging Ultra Capacitors Using Car Battery Charger


Back at the antique log splitter I connected the capacitor bank in place of the starting battery. Now for the test. Will the capacitor bank start a gas engine? I was not sure. Chris was very doubtful.


Well the engine fired right up into life. I shut off the engine and then started it again. Then I shut off the engine again and pressed the start button. The engine turned over a few times but the capacitor bank was draining a bit.


I should have left the engine running a few minutes to recharge the capacitor bank. Then I am sure it would have started again each time with no problem.


Bank of UltraCapacitors starting a gas engineBank of UltraCapacitors starting a gas engine


But this little bank of about 80 Farads in supercapacitors did start the engine two times and nearly started it a third time before it was run down.


We were both quite surprised. Another important note is that the wires were warm to touch but not hot. I was also surprised at this result.


I will continue experimenting with replacing lead acid starting batteries with Amperics supercapacitors. Stay tuned.


You can get Amperics 400 Farad 3 Volt supercapacitors here: Amperics SuperCapacitors


Scroll down the page some to find the supercapacitors.


You can watch today's video here: Starting 11 HP Log Splitter Engine On 5 Supercapacitors


While you are over there please subscribe to my YouTube channel and follow our daily videos as we strive to become self sufficient and off the grid on a budget.

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Troy Reid


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