Portable power for un powered hangar

kyleb said:
Why not install a small invertor and power things off of your car?
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This makes a lot of sense. Connecting the battery in your car to a pure sine wave inverter is a no muss, no fuss solution. You can run your car engine at idle and the alternator will provide a continuous charge to the battery which powers the inverter, providing reliable AC power as long as there's gas in car's fuel tank. A Kisae 2000 watt inverter or similar costs about $280.00.

Kisae 2 kW Inverter.jpg

KISAE SW1220 2000 Watt Pure Sine Wave Power Inverter | DonRowe.com
 
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Stan Cooper said:
This makes a lot of sense. Connecting the battery in your car to a pure sine wave inverter is a no muss, no fuss solution. You can run your car engine at idle and the alternator will provide a continuous charge to the battery which powers the inverter, providing reliable AC power as long as there's gas in car's fuel tank. A Kisae 2000 watt inverter or similar costs about $280.00.

View attachment 93734

KISAE SW1220 2000 Watt Pure Sine Wave Power Inverter | DonRowe.com
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Hmm, I doubt your car would power this for more than 10 minutes at 2000 watts. You can't get blood from a rock, there is no free ride.

Frequently Asked Questions About Power Inverters | DonRowe.com
 
PaulS said:
Hmm, I doubt your car would power this for more than 10 minutes at 2000 watts. You can't get blood from a rock, there is no free ride.

Frequently Asked Questions About Power Inverters | DonRowe.com
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Paul, a couple of points:

1) That FAQ only discusses the length of time a fully charged battery of a given amp-hour rating will last for a given load (which may, or may not be the load the OP has on the inverter).

2) Nowhere in the FAQ does it address continuous battery charging from the car's electrical system alternator. The stock alternator in my 2016 Toyota Corolla is conservatively rated at 13.8 volts, 80 amperes continuous. That is 1,104 watts. With a 90% inverter efficiency, the continuous load of 1,000 watts is realistic. The OP is talking about AC powered tools and a light. Unless the power tools he's talking about require more than a kilowatt continuously, he should be able to power them from the car's electrical system with the engine running until it runs out of gas.

High output alternators of up to 240 amps are available for my car at reasonable prices.

I'm not suggesting there's a free ride.
 
Stan Cooper said:
Paul, a couple of points:

1) That FAQ only discusses the length of time a fully charged battery of a given amp-hour rating will last for a given load (which may, or may not be the load the OP has on the inverter).

2) Nowhere in the FAQ does it address continuous battery charging from the car's electrical system alternator. The stock alternator in my 2016 Toyota Corolla is conservatively rated at 13.8 volts, 80 amperes continuous. That is 1,104 watts. With a 90% inverter efficiency, the continuous load of 1,000 watts is realistic. The OP is talking about AC powered tools and a light. Unless the power tools he's talking about require more than a kilowatt continuously, he should be able to power them from the car's electrical system with the engine running until it runs out of gas.

High output alternators of up to 240 amps are available for my car at reasonable prices.

I'm not suggesting there's a free ride.
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Only caveat to that is what output is of the car alternator at idle, unless you're going to have someone sit and hold the rpms up while you use the inverter. Not to mention it's pretty inefficient using a 140+HP engine to make 2,000w of electricity. Occam's razor still points back to a compact gas-powered genny.
 
SoonerAviator said:
Only caveat to that is what output is of the car alternator at idle, unless you're going to have someone sit and hold the rpms up while you use the inverter. Not to mention it's pretty inefficient using a 140+HP engine to make 2,000w of electricity. Occam's razor still points back to a compact gas-powered genny.
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Alternators, unlike D.C. generators, provide high current output at relatively low engine RPM. Admittedly, it's not hugely efficient, but for occasional use it should work well. This exact setup was suggested in an article written by a U.C. Berkeley electrical engineering professor for providing A.C. power to refrigerators and some lights during our NorCal wildfires and utility power outages the past couple of years. He said the main thing to remember was the car with the engine running should be outdoors and the inverter close to the car using heavy gauge wire to connect the positive and negative battery terminals to the inverter, and a 30 amp outdoor extension cord into the house to power the fridge.
 
SoonerAviator said:
Only caveat to that is what output is of the car alternator at idle, unless you're going to have someone sit and hold the rpms up while you use the inverter. Not to mention it's pretty inefficient using a 140+HP engine to make 2,000w of electricity. Occam's razor still points back to a compact gas-powered genny.
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Its all horses for courses. If your need is 10 minutes a month for 250W, you should probably go a different path than if you need 1500w for hours at a time. Up to 750-1000w, if my need was for minutes (not hours) at a time, I'd go invertor. If I was gonna run heavy stuff or needed power for longer, I'd consider a generator. One thing to consider is that if you get a generator, it'll be one more thing to refuel and maintain.
 
Stan, by the time you install a high amperage alternator, plus a connector and cable system to run the inverter plus the cost of the inverter you could have easily paid for a generator. The car uses a fair amount of that 80 amps to run it's computer, injectors, fans and other things. It seems like a good idea at it's face value, but a little digging and it's a very inefficient way to do it, plus the wear and tear on your car.
 
After the October, 2019 Kincade fire where we lost power for four days, we ordered a 4400 watt dual fuel (gasoline/propane) Westinghouse inverter/generator for the house. It powers the fridge, DirectTV, U-Verse internet router, a few lights, microwave oven, and coffee maker. It worked well last year during the PG&E PSPS power shutoffs due to high winds causing potential wildfires started by downed power lines. We use propane because its shelf life is longer and it's safer than gasoline.

This thread started because the OP was looking for a way to provide A.C. power in his hangar and even suggested using a car in his first post. I really believe the easiest and simplest solution is an inverter off the car battery with the engine running at idle. The OP's load of power tools and compressors is intermittent and the battery acting as a buffer between the car's charging system and the intermittent nature of the inverter load (power tools) shouldn't require a higher capacity alternator or anything else. Wear and tear on the stationary car with the engine idling? Not much.

My $.02. Take it or leave it.
 
Huckster79 said:
Harbor freight has a little two cycle generator for $125... at that cost who cares about parts... use it a few years when it goes get a new one, especially if you are in a t hangar, bicycle lock it but if it walks away your day isnt ruined...
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The Predator line at Harbor Freight actually gets really good reviews. I have a 3000w for work and it is solid. While Honda is the gold standard, for a hangar generator the Predator can't be beat for the price.

For as little as it would be needed, occasional trip to the gas station seems like much less hassle than keeping a solar generator charged and transported back and forth.

https://www.harborfreight.com/2000-watt-super-quiet-inverter-generator-62523.html
 
As somebody mentioned earlier, you could probably run one of those 1800W inverter suitcase generators off the avgas you sump anyway. Just keep a GATT jar around to filter out the water and crud.

Honda $1100
Champion $499
Predator $460
 
All great ideas. Mini cheapo generator on the list, I've got an air tank from my track days for filling tires, and the previous hangar resident left me a rusty rolling tool box, an old gill batery, a squeezy 90 degree angle bottle with some unkonwn fluid in it, two pallets to keep boxes dry when the rain run off gets in to the old port-a-port the management at Calhoun second handed from McCollum for the price of removal, and a servicable lock. What more can life offer? Oh yeah, heat (propane indoor room heater) and a way to get some engine heat to the old boy. Maybe a solar panel for that and or a trickle charger.
Pacer n' Marylene.jpg
 
Stan Cooper said:
Alternators, unlike D.C. generators, provide high current output at relatively low engine RPM. Admittedly, it's not hugely efficient, but for occasional use it should work well. This exact setup was suggested in an article written by a U.C. Berkeley electrical engineering professor for providing A.C. power to refrigerators and some lights during our NorCal wildfires and utility power outages the past couple of years. He said the main thing to remember was the car with the engine running should be outdoors and the inverter close to the car using heavy gauge wire to connect the positive and negative battery terminals to the inverter, and a 30 amp outdoor extension cord into the house to power the fridge.
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I understand that they can be used for emergencies to power low-draw items. Alternators DO put out decent power, but most auto alternators are 100-130amp rated and only put out about half that at idle rpm (usually around 600-700rpom), which means you likely have ~700w of available power. To get full rated power the rpm generally has to be over 1,000rpm, which means having someone sit in the car to keep rpms up. Service vehicles often have a high-idle switch to power the increased power needs of lights/winches/etc. because the alternator won't do it at idle. Sure, it'll work fine for powering an LED light or charging a phone. If you are plugging in a cordless drill charger, it'll pull 300-400W. Plug in one more item and you're out of power while at idle. If it's raining, I really don't want my hood up on my car with an inverter laying there in the rain along with the other vehicle electronics. Generator sitting in the rain? Who cares (or lay a piece of scrap wood on top of it). I guess I just prefer having the power "solution" be independent of other items like my primary mode of transportation. It's one thing to cobble something together in an emergency (like your NorCal incident), but that's more of a work-around for not having access to a portable generator.
 
Scott MacKie said:
All great ideas. Mini cheapo generator on the list, I've got an air tank from my track days for filling tires, and the previous hangar resident left me a rusty rolling tool box, an old gill batery, a squeezy 90 degree angle bottle with some unkonwn fluid in it, two pallets to keep boxes dry when the rain run off gets in to the old port-a-port the management at Calhoun second handed from McCollum for the price of removal, and a servicable lock. What more can life offer? Oh yeah, heat (propane indoor room heater) and a way to get some engine heat to the old boy. Maybe a solar panel for that and or a trickle charger.
View attachment 93749
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A generator and some type of heater can solve the cold start issue. Or better yet a tanis type setup mounted to the engine. Those work great.
 
SoonerAviator said:
I understand that they can be used for emergencies to power low-draw items. Alternators DO put out decent power, but most auto alternators are 100-130amp rated and only put out about half that at idle rpm (usually around 600-700rpom), which means you likely have ~700w of available power. To get full rated power the rpm generally has to be over 1,000rpm, which means having someone sit in the car to keep rpms up. Service vehicles often have a high-idle switch to power the increased power needs of lights/winches/etc. because the alternator won't do it at idle. Sure, it'll work fine for powering an LED light or charging a phone. If you are plugging in a cordless drill charger, it'll pull 300-400W. Plug in one more item and you're out of power while at idle. If it's raining, I really don't want my hood up on my car with an inverter laying there in the rain along with the other vehicle electronics. Generator sitting in the rain? Who cares (or lay a piece of scrap wood on top of it). I guess I just prefer having the power "solution" be independent of other items like my primary mode of transportation. It's one thing to cobble something together in an emergency (like your NorCal incident), but that's more of a work-around for not having access to a portable generator.
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With a 700 watt load you're "out of power" if your load is 100% duty cycle. For intermittent loads the charged battery provides the additional power required for the minute or two the drill motor is actually energized. Jeez.
 
Stan Cooper said:
With a 700 watt load you're "out of power" if your load is 100% duty cycle. For intermittent loads the charged battery provides the additional power required for the minute or two the drill motor is actually energized. Jeez.
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I'm not talking about powering a drill motor. I'm talking about a battery charger FOR a cordless drill. Many of them run around 5-7A @ 110/120V while charging (~700W). So, let's say he gets the Ryobi 18V cordless drill/inflator/flashlight for the hangar. How does he charge the batteries with your inverter and do anything else productive? One item plugged in could sap all of the available wattage from the inverter with the car at idle (call it 60A x 13V = 780W). So now he has to sit around for 30-45 minutes waiting for the batteries to charge so that he can use the drill/inflator. OR . . . he gets a small gas generator and he can charge batteries and run a small air compressor, and listen to the shop air-band radio, etc. simultaneously.

Either method CAN work. One of the methods is infinitely easier and allows for many items to be used simultaneously . . .the other means you have to be judicious with your chosen power. Both are going to require gasoline to generate the power. Jeez.
 
If he has the dough, a 5kw of solar panels and a tesla battery would probably give him all the power he needs. If he's opposed to burning gas for a generator

But a cheap generator is probably best. I'd get a 4 stroke and a small gas can. Refill the gas can every few months, dumping the older gas in his car. Should have no issues.
 
SoonerAviator said:
I'm not talking about powering a drill motor. I'm talking about a battery charger FOR a cordless drill. Many of them run around 5-7A @ 110/120V while charging (~700W). So, let's say he gets the Ryobi 18V cordless drill/inflator/flashlight for the hangar. How does he charge the batteries with your inverter and do anything else productive? One item plugged in could sap all of the available wattage from the inverter with the car at idle (call it 60A x 13V = 780W). So now he has to sit around for 30-45 minutes waiting for the batteries to charge so that he can use the drill/inflator. OR . . . he gets a small gas generator and he can charge batteries and run a small air compressor, and listen to the shop air-band radio, etc. simultaneously.

Either method CAN work. One of the methods is infinitely easier and allows for many items to be used simultaneously . . .the other means you have to be judicious with your chosen power. Both are going to require gasoline to generate the power. Jeez.
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The specifications for the Ryobi 18V ONE+ charger:
  • Battery: 18V Lithium-Ion or NiCd
  • Input: 120V, 60 Hz, 85 W
  • Output: 18V DC, 3.0 A
  • Cord: 6 ft.
  • Tool Weight: 1.5 lbs.
While charging, the 120 VAC input is 85 watts, not 700 watts. I think you're using the charger output current (3.0 A), but that's at 18 volts, which is 54 watts.

18V ONE+™ DUAL CHEMISTRY CHARGER | RYOBI Tools
 
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That Aldi knockoff of the Honda generator is perfect, especially if you bought one of the last three on clearance for half price; $150.... It runs fine on standard gas. Now I’m intrigued to try 100LL in it after some suggestions.

I don’t have a hangar (waitlist), so I’ve found a lot of the 18V battery tools very useful. Just picked up a Ryobi wax buffer/polisher that buffed wax on/off my Bonanza twice with two batteries used.
 
An alien dropped into this thread from outer-space could think that pilots are opinionated.
 
Stan Cooper said:
The specifications for the Ryobi 18V ONE+ charger:
  • Battery: 18V Lithium-Ion or NiCd
  • Input: 120V, 60 Hz, 85 W
  • Output: 18V DC, 3.0 A
  • Cord: 6 ft.
  • Tool Weight: 1.5 lbs.
While charging, the 120 VAC input is 85 watts, not 700 watts. I think you're using the charger output current (3.0 A), but that's at 18 volts, which is 54 watts.

18V ONE+™ DUAL CHEMISTRY CHARGER | RYOBI Tools
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I think I was converting with the output amperage from a Dewalt charger not realizing it was listing output vs input, my mistake. Should have thought about it objectively that a low amp battery charger wasn't going to draw 700w like a refrigerator or vacuum cleaner.
 
Huckster79 said:
Harbor freight has a little two cycle generator for $125... at that cost who cares about parts... use it a few years when it goes get a new one, especially if you are in a t hangar, bicycle lock it but if it walks away your day isnt ruined...
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I like this one, keep your 1 gallon gas can there to dump your av-gas in when you sump the tanks. When 1/2 full or full add 2 cycle oil and dump in the generator. Note I have seen these generators on sale for $89.

won't run a compressor but could charge a battery for a 12 volt inflator/drill/driver etc.
looks like Harbor freight may have discontinued theirs. but can still by a similar one at Lowes and other places.

https://www.lowes.com/pd/All-Power-...uPQ1Bpa0FXP8dsjQppBoC7IAQAvD_BwE&gclsrc=aw.ds



Brian
 
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