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.

 

[spokewrench]

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.

I would have loved to buy a small diesel generator if I could find one. Suppose it was only 2,000 watts: I wonder what it would weigh. If a diesel needs a battery to start, fine!.

For years we had a small diesel tractor on the farm. It had the power to bush-hog but was thrifty keeping a PTO chipper spinning. It sat idle for weeks or months, and I don't remember any fuel system trouble. Just remember to keep the battery charged!

 

[spokewrench]

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.

I thought about it. Maybe $200 for 400 watts of panels. I ordered my power station from a company that also has 400 watt solar panels, but they don't say how long they would need. Maybe that's because it would depend on the intensity of the sunlight.

I've lived here 45 years. The longest outage I remember was a week in winter in 2002, I think. I stayed with relatives 4 miles away, who had power, so gasoline must have been available. I think the recent 4-day outage was the second longest. A couple of gallons of gas and a lithium battery might have been enough. If not, I would have needed to set up panels in adequate sunlight. I don't know much about that.

Most outages around here are under 24 hours. My gas furnace needs 600 W at 120 VAC. A light switch by the furnace can shut off the power. If I replace it with an outlet and plug, I can run the furnace from a power station to get gas heat during a winter power failure.

Do you mean your van would power your house from its alternator? If it's not diesel, I wonder if you'd be depleting your gas tank for very little electrical energy.

 

[dodgeman]

I have 6500 watt generator, gas powered, very loud and not very thrifty. I usually have 5 gallons of gas on hand sometimes less. I mainly have just used it for our fridge and freezer and could probably go a couple of days running it just occasionally. I woukd have all sorts of fuel on hand in three vehicles but getting the fuel out would be a chore.

 

[Roamers]

Do you mean your van would power your house from its alternator? If it's not diesel, I wonder if you'd be depleting your gas tank for very li

No, Battery and Solar. It will run the essentials.

 

[mschwett]

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.

Is your math right on the refrigerator? if 2 gallons is 3.4 kw for 3.5 hours that’s 6kwh Per gallon. if your refrigerator needs 1.3kw in summer per day, a single gallon should get you over four days, not 3.4 gallons per day. our electric loads are very minimal (no AC or other big users) so I may look into getting the required gear to safely plug our EV into the main circuits, with 80kwh it ought to last us more than a week.

 

[PCeBiker]

Keep in mind that a gasoline engine is just like an ebike motor, and is most efficient at about 80% of it's maximum output.

This is the generator that I wanna get,..

It runs for 3 hours at maximum output (900 watts continuous), so if all things are equal, it should run 4 times longer at 25% output, but it only lasts just over twice as long.

It's only about 30 pounds with gas, so it's easy to carry, and it's just under 50cc so I can use it legally as a bicycle engine.

It is more than the 500 Watt Canadian ebike limit, but if it's powering the ebike with 500 Watts, and charging a battery with the remaining 400 Watts, I might be able to float through the legal gray area.

 

[stompandgo]

Those Hondas work great for small loads. Strapped to the back of a bike, you're nuts.

When I lived in western MA, I had a shed way out back about 150 feet from the house. I had a permit from the fire department to store up to 50 gallons of gas. I used Sta-Bil in every jug, and would rotate jugs out for lawn and garden use (pre-electric lawn implement days). My 14hp twin cylinder generator used about a gallon an hour at normal loads. That would give me between 3-5 days of runtime. We had a 4 day outage, and I still had some left.

 

[6zfshdb]

I have an old Honda EX750 generator, which is the predecessor of the newer EU1000i. I used to take it camping and charged my e-bike batteries with it overnight. It was quiet enough so it didn't disturb others in the campground.

Just for kicks, I once considered trying to adapt it to charge a bike while riding. It weighs just 26 pounds, about the same as two 20AH batteries, but mounting it on a bike would be problematic. It would be much more practical on a trailer. At my age, I'm not into camping or bike packing anymore. For the same weight, I can carry two batteries, which gives me a 100+ mile range. That's about all I can handle in a single day.

I did see someone doing this when he passed me on the C&O Canal trail in MD. three years ago. I wanted to talk to the guy, but I couldn't catch up to him. I'm curious about the legality of a gas engine charging an electric bike. Would it still be considered an e-bike?

 

[6zfshdb]

I would have loved to buy a small diesel generator if I could find one. Suppose it was only 2,000 watts: I wonder what it would weigh. If a diesel needs a battery to start, fine!.

Before I decided to go for a bigger whole house diesel, I looked at this small Yanmar:

It's just 1500W, but enough for the fridge and a few lights. It would work well to charge your LiFePo batteries. If you heat with oil, you have a ready supply of fuel on hand with no worries about storage or flammability issues.

 

[teskow]

I am now seeing some articles about Nissan and Subaru experimenting with autos with electric propulsion only to the drivetrain. They have a constant running small gasoline generator on board that runs at an almost constant economical and efficient speed charging the battery. I tam pretty sure I was on an electric city bus like that in Norway or it may have been Sweden. You could hear a slight drone of an ICE in the background.

 

[spokewrench]

Is your math right on the refrigerator? if 2 gallons is 3.4 kw for 3.5 hours that’s 6kwh Per gallon. if your refrigerator needs 1.3kw in summer per day, a single gallon should get you over four days, not 3.4 gallons per day. our electric loads are very minimal (no AC or other big users) so I may look into getting the required gear to safely plug our EV into the main circuits, with 80kwh it ought to last us more than a week.

According to the generator manufacturer, the generator will produce 850 W for 7 hours per gallon. That would be 6 kWh per gallon, as you say. That's about 16% efficient compared to the 36.6 kWh in the fuel. I hesitated to buy a gas generator because with lighter loads they are even less efficient.

I found that with no electrical load, my generator also burned a gallon every 7 hours, or 3.4 gallons per day. That would burn gasoline with 124 kWh of energy. Leaving it running to provide 1.3 kWh to a refrigerator would waste about 99%.

If I could charge a power station at more than 800 watts, the generator could evidently be 16% efficient so that a gallon of gas would last me 16 times longer. I'm overlooking losses in the battery's charging efficiency and in the inverter changing battery voltage to 120 AC. I've got meters that measure watt hours, so I'll be able to measure when the power station arrives.

I've read that power stations should be exercised. Mine is rated at 1800 W continuous and 3600 surge. No more reeling out 50 yards of extension cords outdoors.

 

[spokewrench]

Keep in mind that a gasoline engine is just like an ebike motor, and is most efficient at about 80% of it's maximum output.

This is the generator that I wanna get,..

It runs for 3 hours at maximum output (900 watts continuous), so if all things are equal, it should run 4 times longer at 25% output, but it only lasts just over twice as long.

It looks 14% efficient at 900 W and 8% at 225.
The Generac XD5000E is a 250-pound diesel rated at 5000 W. It seems to be 17% efficient at 2500 W. I'm surprised home generators aren't more efficient, especially diesel.

 

[Roamers]

I'm surprised home generators aren't more efficient, especially diesel.

If you can also take advantage of the heat they produce, pretty efficient!

 

[RunForTheHills]

If you can also take advantage of the heat they produce, pretty efficient!

Lol! I wouldn't recommend running it in the house...

 

[PCeBiker]

Lol! I wouldn't recommend running it in the house...

Like the people that bring their propane BBQ into their tent to keep warm when they're camping, and wake up dead.