Generator Size...

[Greg Cuetara]

with the recent power outage up here in the northeast the LOML has decided that she wants me to look into a generator for the house. We have a wood stove and last week it kept the house at 75-80 so not too worried about heat but it would be nice to have running water and keep the fridge going. I know there are issues with trying to get the water pump going so I will leave that one out there right now. My question is to run a fridge and other misc. appliances how many watts should I be looking at for a generator.

Thanks,
Greg

[John Coloccia]

I have a 5kw generator running my water pump, lighting, furnace and fridge. I can run a router, shop vac and drill press (not at the same time if course). I just need to be sure no one is running the water at the same time or it will kick out. With a 5 gallon tank, it runs for about 10 hours. I'm borrowing this from a friend. If I buy one, I will buy a larger unit that will power my whole shop as I can't afford to be down for weeks at a time, abd that appears to be the new norm in Connecticut. How I wish I could fire my power company.

[Leo Graywacz]

I'm running a 5KW too. I have city water so no need to run a pump. I run my oil heat which takes care of heating the house and the hot water (side saddle tank). I run a sump pump, so it comes on when needed. I run my refrigerator and a smaller freezer. I also run my 50" plasma, my laptop, my desktop and peripheral computer equipment. I run lighting where I need it. I don't keep it on in rooms that aren't being used as happens when I am on the grid.

I have a Husky generator that has a Subaru engine. I've had the tank last 16 hours, it is about 6 gallons. It says at 50% load it will run about 12 hours. I just got it, cost just over $600 and it is worth every penny. With the gas prices as they are it costs me about $20-25 to live like I did on the grid.

[Joe Pelonio]

My Generac is 6kw and when the power goes out I can run the furnace ( fan, it's gas) refrigerator or freezer (change off every 2 hours) and several lights, plus one TV and cable box and charger for cell phones. The microwave is 1,200 watts and when I tried to run it the cord got hot so we stick to the gas stove/matches and for oven use the gas grill.

[Leo Graywacz]

You should be able to run a lot more than that on 6KW. As for the cord getting hot, you just need a larger one. If you are running 14ga cords that are 50' long it is probably to small to run any large current drawing device because the voltage drop across it will do just what you noticed, heat up the cord. You should be using 12ga and 10ga cords.

[Greg Cuetara]

ok so it looks like 5kw would be ok for emergency situations. The other question is do you guys have it wired directly into a separate panel or do you just run extension cords....

[Myk Rian]

4400 watts keeps us warm, with water, some lights, and the computer with no problems.
I didn't install a transfer switch, but we do disconnect the main breaker. (And I don't need any comments about that).
I plug it into the breaker box in the garage with a 220 cable.

[Scott T Smith]

I live on a farm. Although we have multiple generators, the permanent backup one is a 5500 watt Onan LPG generator with an automatic transfer switch (ATS). The ATS feeds a subpanel that has the critical circuits. We have no problems pulling the well pump, chest freezer, kitchen freezer, the furnace blower (we have LPG heat), the fans/lights in the horse barns and some misc lights spread throughout the house.

With it's 125 gallon propane tank, it's good for about 3.5 days of continuous runtime.

[Leo Graywacz]

Wow, that's a lot of fuel. With my 5KW gas genny I would do about 10 days on 125 gallons of gasoline

[Matt Meiser]

I don't think 125 gallons of propane has the same amount of energy as 125 gallons of gasoline. We get about 8 hours from our 6500W generator. I had the gas meter sized and plumbing run for a standby though and will do that when we recover from a lot of big house projects and a big vacation this year. The generator sitting in the garage doesn't do much good if I'm not home to hook it up.

[John McClanahan]

I have an Onan 4KW motorhome generator that I am setting up to run on propane. From my research, 4 pounds of propane equals 1 gallon of gasoline. A 20# grill bottle is equal to 5 gal.can of gas. Note that the propane is in pounds, not gallons. Anyone know how many pounds a gallon of propane weighs?

John

[Joe Pelonio]

50' 10 gauge extension cords from the driveway outside the garage door, through the garage and into the house. Usually once or twice a year so no need for wiring it into the system.

[Ted Calver]

I have a tri-fuel (nat gas, propane or gasoline) that I picked up at Northern Tool because ice storms and hurricanes were leaving us without power for a week or so. I got the tri-fuel because after awhile people ran out of gas and none of the gas stations were able to pump. It runs fine on natural gas and there are no worries looking for fuel. I think it's an 8k. We've had it for about seven years and have had no need for it. The wife was afraid when Irene came through so I put oil in it and hooked it up. It ran like a champ. We lost power for all of 30 seconds.

[Leo Graywacz]

I figured that as soon as I got the new generator home the power would come back on and never go off for more than a few seconds. You can call it what you want, I call it insurance.

But that didn't happen and the new genny got a good workout.

[Larry Frank]

For those who run heavy duty cords, how do you wire it to your well pump? My pump is 220 and the generator has a 220 plug but it has 4 prongs and wires. I would rather avoid putting in a transfer switch.

[Matt Meiser]

One of those is a neutral which your well probably doesn't use. Just 2 hots and a ground. You'll have to consult a wiring diagram for the receptacle to see what's what.

[Rod Sheridan]

One item I would add to Matt's comment is that if you are using a generator with temporary wiring (no transfer switch) make sure the model of generator you purchase has the neutral bonded to the frame, and connect the frame to a good ground such as a well casing, municipal water supply or your main electrical ground.

Regards, Rod.

[Matt Meiser]

FYI, we were just at Costco yesterday and they are now selling a 12KW Generac generator with a 100A transfer switch (with a Honeywell sticker on it, but its obviously a Generac and inside the xfer switch the label says the Honeywell name is being used under license by Generac) for $2400-2600--can't remember for sure. Probably not available in the northeast right now, but if anyone is looking that seems to be a really good deal. The included transfer switch is one that can interrupt 2 AC units and it looks like it comes with the indoor monitoring display. For me, that would power all our essential needs, i.e. a lot of house circuits, plus our heat pump, but not my shop since we'd have to put in a 100A subpanel and move all the emergency circuits to that.

Rod, I never thought about that as a ground, but around here new wells around here use PVC casings.

[Curt Harms]

I saw what I think is a clever fairly inexpensive alternative to conventional transfer switches. I've looked for it just now and can't find it. It's a sliding sheet metal affair that mounts in the service panel. You put a breaker able to handle the entire generator load in the upper right hand slot. Connect the generator to that breaker. This mechanism is designed such that either the main breaker or the generator breaker can be closed. Both cannot be closed at the same time due to the cutouts in the plate. The main breaker had to be in the off position in order to engage the generator breaker. The text said it was legal in some places, not legal in others.

[Scott T Smith]

Wow, that's a lot of fuel. With my 5KW gas genny I would do about 10 days on 125 gallons of gasoline

LPG has 74% of the energy of gasoline. Propane companies will only fill a tank to 75% of capacity, so a 125 gallon tank typically contains 94 gallons when it's full. Thus, if I'm doing the math right 94 gallons of propane has the same energy as 70 gallons of gasoline.

3.5 days of full operation equals 84 hours, which would be an equivalent gasoline consumption of .83 gallons of gasoline per hour, and 1.12 gallons of propane.

Typically we're pulling about 75% load on the generator during an outage (spiking up to 100% when the well is running), so the consumption comparison is pretty much in line with the watt per gallon stats for most small generators.

[Bill Edwards(2)]

A few volts: :D

http://www.billsid.com/img/bats.jpg

[Leo Graywacz]

Hey Bill, your signature is from M*A*S*H*, correct. The little roaming Korean salesman said it.

[Mike Cutler]

Greg

How do you heat water? If you're not using electricity, a smaller inverter style generator will work just fine.
During the last storm I hung a clamp on amp meter on the generator wiring just to keep track of amps. The highest amps I recorded was 17 amps when I used the hor water heater by itself. Normal loads, including a 240 well pump hovered at about 11 amps.
The fridge was about 3-4 amps, and the freezer was 2-3 amps, lights were maybe 2 amps, but I use almost all CFL's.
Inductive loads were the bigger problem. Those motors kicking on dragged the generator down for a few moments while it caught up.
I used a small 4000watt Coleman Powermate, with a Tecumnseh 8HP motor, and a mechanical govenor. I backfed the main panel through the garage subpanel, Illegal and dangerous as all get out but, you do what you have to do.
My plan is to install a generator transfer panel, and get a 6000w inverter style generator. I worried about the electronics on the appliances with my current generator. It's pretty ratty AC when observed with an O-Scope, which I did for fun.

Believe it or not it was the coffee maker that caught me off guard. That little bugger was 1500 watts.

The way I installed my generator was wrong. As I stated, it's illegal and dangerous to backfeed panels like I did, and I can't recommend that you do it. I missed multiple days of work to keep everything going and safe for me.
Get the right stuff. Get a transfer panel and move your loads over properly, keeping ground and neutral at the correct potential. In all eventuallity you'll find that most of the loads you want to transfer too, are the ones the NEC requires to be on their own circuits anyway, ie, kitchen receptacles, fridge, bathroom receptacles, furnace, gas water heaters and vents etc.

A transfer panel is not that expensive. Depending on the length of wiring, the wiring may cost more than the panel,

[Bill Edwards(2)]

Hey Bill, your signature is from M*A*S*H*, correct. The little roaming Korean salesman said it.

Correct.

The actor was Richard Lee Sung.

212265

Burns and Hot lips hired him to carve a bust of the Coloniel.

[Eddie Watkins]

We had a tornado come thru about a year ago and was without electricity for a week. I have a 12hp gasoline unit that says it will deliver 8.5kw. It took 10 gals of gasoline a day to run and it would run everything in the house except the 2 AC units. It would run the furnaces, tho. I tried them just to see if theywould work in case of an ice storm in the winter. I did not try my shop, tho. We did make sure everything was off that wasn't being used but we are on a well which worked fine. Water heaters were both NG. The wire I plug in is an 8 guage wire probably 40" long, I think. The wire cost $200-300 by itself.

[Orion Henderson]

Well, after three power outages of more than 48 hours this year alone we bought a generator. Managed to snag a no name off the back of an 18 wheeler (legally-we bought it I didn't steal it). By the time I got it home power came back. That said, it's a 5000 watt gas generator. Our well pump takes 2K, so that leaves us plenty for the fridge, freezer, furnace, and some lighting. We have a propane stove, dryer, and heat. We had an electrician get us a new breaker box with a generator control on it (much cheaper than a transfer) and wire up a 220 4 wire outlet in the garage. Have a 50' cord on order should be here in a day or two. Haven't had the chance to test it yet but my neighbor runs his whole house the same wattage. He backfeeds through his stove outlet which seems a little dangerous. As said above by someone in Connecticut-the appears to be the new normal so we are adapting. I can't imagine needing more than 8000 watts if your house runs on electric everything and a well. Our goal was to be comfortable not pretend there was no outage. Those standby Generac's are awesome, but they triple the price.

[Greg Portland]

Consider how often the power is out and how long you'll run the generator. If you're not running it for long periods of time then fuel economy may not be as big an issue. Also, take a close look at used generators. My parents got a great deal on a 4cyl propane generator (over 20KW IIRC) because it was bigger than what most homes were looking for but it was too small for most businesses.

[Mike Archambeau]

with the recent power outage up here in the northeast the LOML has decided that she wants me to look into a generator for the house. We have a wood stove and last week it kept the house at 75-80 so not too worried about heat but it would be nice to have running water and keep the fridge going. I know there are issues with trying to get the water pump going so I will leave that one out there right now. My question is to run a fridge and other misc. appliances how many watts should I be looking at for a generator.

Thanks,
Greg

Greg....if you think you will be home when the power goes out i.e. not travelling, then you could and should buy a portable standby generator with a manual transfer switch. This is because you can run the generator only when you need power. What this means is you can run your generator long enough for the refridgerator/freezer to get cold, heat hot water for showers and dish washing, have water from your well to flush toilets, etc. But then you can turn it off and not burn fuel needlessly when you don't need to generate electricity.

A generator with an automatic transfer switch will fire up within seconds of sensing the loss of line power, and it will continue to run until line power is restored or you run out of fuel whichever comes first. This is a fine option if you have enormous fuel storage, need to generate large amounts of electricity continously, and are not home at the time.

Regardless of which way you go, you definitely need a transfer switch (think of this as a small electrical panel with the circuits you want to use when line power is not available; like well pump, refridgerator, boiler, kitchen outlets, etc.) If you choose a manual trasfer switch, you start the generator and then throw the main breaker on the transfer panel. These are simple to wire. You can run a drop cord from the generator to a box on the wall that is wired to your transfer switch panel.

I went with a 6000 watt portable standby generator, manual transfer switch. I wired the backup circuits myself (I am not an electrician, but I am an engineer and pretty good with tools and not afraid to roll up my sleeves.) The job was pretty straight forward. Took me a Saturday morning to have it all wired and operational.

On my 6000 watts, I can operate my well pump, boiler, 2 refridgerators, and a couple of outlets in the kitchen and family room for a lamp, TV, or radio.

Like you we have a woodstove so we can make ample heat. And I am in the process of adding a coal stove, so will have that as a backup heat source as well.

One thing to think of very carefully is reliability. When the line power is not there you NEED your backup generator to run reliably. Buy the best unit you can find and keep it in top condition. That way it will perform when you need it to.

I spent about $2500 for a Cummins Onan 6000 watt portable generator with a manual transfer switch back in 2003. Add in a Saturday of free labor and we were operational. The unit burns less than 1 gallon of fuel per hour at full load. If you run one of these twice a day for two hours each time at full load, you can run your household safely, on less than 4 gallons of fuel per day. So plan ahead and have some gas on hand. Your car or truck is a fine source of fuel in a pinch if you have a means of siphoning fuel from the tank.

If you think you will use a generator for 10 years, and you spent $2500 on it, that works out to $250 dollars per year. A good one will last 20 years, so it works out to $125 per year. That sounds like an awfully inexpensive way to take care of your family when the fragile power grid is not working. If you are able bodied I think it is a wise thing to put in place. And if you move, you can take the generator with you.....it rolls like a wheel barrow!

Hope this helps you size things up. I am happy to answer questions if you have any.

Good luck with your project.

[Bill Cunningham]

I run a 5.5kw Coleman that I picked up at Costco a few years back when we had a massive power outage..In an emergency, I can plug it into the shop panel and feed 220 back to the house, (I disconnect the main breaker from the street line).. It powers both the shop and the house. The only thing I can't run is the Stove in the house, and the Compressor in the shop. Both draw too much.. But with a Microwave you don't need a stove, and our water heater only draws 3 amps (gas, wall mounted flowthough type), and furnace is also gas and low amps..

[Von Bickley]

I have a 4000 watt generator with the Subaru engine that I bought at HF. My generator also has electric start because I have heart problems. My generator is wired into a small electrical panel that has manual transfer breakers. I have to manually turn off the electrical power from the power company before I can turn on the generator power.
My generator will run my water pump, 2 refrigerators, 1 freezer and a few lights.

[Jim Laumann]

I've got a 6kw unit, bought it back in '91 when we had a rain/ice/snow storm hit on Halloween - we were out then for 6 days, 6 hours, and have had other smaller outages since then. Has a 11 hp Honda engine - sweet running unit - starts on the 1st/2nd pull. Runs off gasoline - sadly, it has a small tank - so it needs to be filled every 2-2.5 hrs.

It puts out 220v, I back feed from my garage to the house (yes - the main breaker in the house must be off). It will run the well, the sump pump, the frig's, freezers, the pump on the hot water boiler (LP gas burner), the micro wave, and some house lights - just not all at once. We have to balance the use of the current - when the govenor on the engine opens up, you know you are pushing the unit. I won't run electronics off it - TV, 'puter, etc - don't know how clean the power is.

[ray hampton]

I've got a 6kw unit, bought it back in '91 when we had a rain/ice/snow storm hit on Halloween - we were out then for 6 days, 6 hours, and have had other smaller outages since then. Has a 11 hp Honda engine - sweet running unit - starts on the 1st/2nd pull. Runs off gasoline - sadly, it has a small tank - so it needs to be filled every 2-2.5 hrs.

It puts out 220v, I back feed from my garage to the house (yes - the main breaker in the house must be off). It will run the well, the sump pump, the frig's, freezers, the pump on the hot water boiler (LP gas burner), the micro wave, and some house lights - just not all at once. We have to balance the use of the current - when the govenor on the engine opens up, you know you are pushing the unit. I won't run electronics off it - TV, 'puter, etc - don't know how clean the power is.

people power computer, tv sets in the car/rvs and stand-by power supply should be as clean as your car power supply