bought a gas generator for myLiFePO power station

[spokewrench]

Twenty months ago this area lost power for 4 days. A neighbor brought in an extension cord from his generator. A gas engine burns a lot of fuel even with no load. He kept it off much of the time. Even then, he and tens of thousands of others spent hours each day searching for an open gas station.

Years ago I quit using uninterruptible power supplies. They didn't store much energy, and the service life of a lead-acid battery wasn't good. LiFePO4 seems vastly better. Greater energy density, faster charging, longer service life. A 1 kWh station might supply basic household needs (not hot water), for 12 to 24 hours. They can be charged to 80% in maybe 50 minutes. This would demand power up in a range where a small gas generator is fairly efficient. It could give you emergency power 100% of the time while reducing fuel needs 90%. Fuel on hand would last 10 times longer.

I ordered a generator and a 1 kWh power station. The generator arrived first. They say on 2 gallons it will produce 3400 watts for 3.5 hours and 850 watts for 14 hours. That's 18% of the energy in the gasoline.

I put in a pound of fuel and weighed it on my package scale: 61.18 pounds. I ran it with no load for 12 minutes and weighed it again: 61.00. In grams, the difference was 81. I put water in a kitchen cylinder until it weighed 81 grams. When I put it on the generator, the package scale again said 61.18. It was verified. It had used 0.18 pounds of gas in 12 minutes. Two gallons would give me 13:20 unloaded, less time than listed 14:00 with an 850 watt load.

Wait. Before having hands free to start the stopwatch, I needed to pull the rope, then shut off the choke. If it had run 36 seconds before I pressed the stopwatch, it would agree exactly with a 14-hour run time. The delay was probably less, but the brief use of the choke would have increased fuel consumption. My figure for no load agrees closely with the published figure for 850 watts.

Each cycle of a gas engines needs a certain minimum of air and gasoline for complete combustion, to reduce air pollution. To keep an unloaded engine from overspeeding, the ignition module may retard the timing, for example. This seems to be why, as the load drops below 850 watts, fuel consumption doesn't drop.

My refrigerator needs 960 watt hours a day in winter and 1300 in summer. That averages 40 and 54 watts. Running the generator continuously to supply my refrigerator would require 3.4 gallons a day.

With three 40-minute charges a day, the power station could supply 1.75 kWh a day for the refrigerator and lots of other uses, and 3.4 gallons would last the generator 10 days. When fuel isn't readily available, fuel economy means peace of mind.

 

[Roamers]

LiFePO4 seems vastly better. Greater energy density, faster charging, longer service life. A 1 kWh station might supply basic household needs (not hot water), for 12 to 24 hours

No comparison! Depeding on your surroundings and power station inputs, consider adding solar. Super inexpensive these days and convenient. If needed, my van will be my power center for the house. 400 AHr LiFePO4 and 440 watts solar; generator if sun doesn't cooperate.

 

[stompandgo]

I'm taking the fossil fuel route and putting in a natural gas whole house standby generator. LNG is cheap, and we use it daily for hot water and cooking, and for heat during the cold months. We lost power for 3.5 days during the last Nor'easter, and I'm done feeding a gasoline generator, running it for 5 hours then shutting down for a rest, and driving around to find a gas station that has power. D.O.N.E done. I was already going to upgrade my electric service to 200A as my panel is full and we have two refrigerators, an electric dryer, and central air. Unfortunately, my gas line is only 1/2" so I am having the gas company upgrade it. Solar is out because we live in a historic district where it can't be on the front of the house or seen from the street. The front of the house faces southwest. We lose power at least four times a year, and with the wack job we have in the governor's mansion, I can forsee more issues down the road. I can be off the grid for as long as need be, including the A/C during the summer.

 

[RunForTheHills]

I have a natural has generator and battery backups (UPS) on all the electronics i care about. It seems like the power goes out once or twice a month here. If it is not weather, Edison is always doing some kind of maintenance.

 

[6zfshdb]

Twenty months ago this area lost power for 4 days. A neighbor brought in an extension cord from his generator. A gas engine burns a lot of fuel even with no load. He kept it off much of the time. Even then, he and tens of thousands of others spent hours each day searching for an open gas station.

Years ago I quit using uninterruptible power supplies. They didn't store much energy, and the service life of a lead-acid battery wasn't good. LiFePO4 seems vastly better. Greater energy density, faster charging, longer service life. A 1 kWh station might supply basic household needs (not hot water), for 12 to 24 hours. They can be charged to 80% in maybe 50 minutes. This would demand power up in a range where a small gas generator is fairly efficient. It could give you emergency power 100% of the time while reducing fuel needs 90%. Fuel on hand would last 10 times longer.

I ordered a generator and a 1 kWh power station. The generator arrived first. They say on 2 gallons it will produce 3400 watts for 3.5 hours and 850 watts for 14 hours. That's 18% of the energy in the gasoline.

I put in a pound of fuel and weighed it on my package scale: 61.18 pounds. I ran it with no load for 12 minutes and weighed it again: 61.00. In grams, the difference was 81. I put water in a kitchen cylinder until it weighed 81 grams. When I put it on the generator, the package scale again said 61.18. It was verified. It had used 0.18 pounds of gas in 12 minutes. Two gallons would give me 13:20 unloaded, less time than listed 14:00 with an 850 watt load.

Wait. Before having hands free to start the stopwatch, I needed to pull the rope, then shut off the choke. If it had run 36 seconds before I pressed the stopwatch, it would agree exactly with a 14-hour run time. The delay was probably less, but the brief use of the choke would have increased fuel consumption. My figure for no load agrees closely with the published figure for 850 watts.

Each cycle of a gas engines needs a certain minimum of air and gasoline for complete combustion, to reduce air pollution. To keep an unloaded engine from overspeeding, the ignition module may retard the timing, for example. This seems to be why, as the load drops below 850 watts, fuel consumption doesn't drop.

My refrigerator needs 960 watt hours a day in winter and 1300 in summer. That averages 40 and 54 watts. Running the generator continuously to supply my refrigerator would require 3.4 gallons a day.

With three 40-minute charges a day, the power station could supply 1.75 kWh a day for the refrigerator and lots of other uses, and 3.4 gallons would last the generator 10 days. When fuel isn't readily available, fuel economy means peace of mind.

Thanks for the detailed analysis! For many years, I went through the same scenario during our frequent power outages. Gasoline use was always problematic for generator use due to availability, shelf life and safe storage issues. Had LiFePo batteries been available back then, I probably would have gone the same route you did.

Where I live, reducing generator gasoline use would only solve part of the problem. I have limited ability to store enough for the prolonged outages we have here. I used to siphon it from my vehicles when local gas stations weren't able to pump.

The ultimate solution for me was to switch to a diesel generator. I fuel it, along with my tractors, from my 1000 gal furnace fuel oil storage tank. I keep it topped off during peak power outage "season", and could easily survive a month or more if necessary. Yes, diesel is more expensive than gasoline but it is more efficient, and without the road tax, is comparable in price to gas.

For those with shorter, less frequent outages, your solution is more practical though.