Portable Generator for Home back up

[Russell]

Buying a generator has been on the list of things to do for a while. Will a 5500 watt (8500 start) be enough?

I don't mind playing musical plugs, but I want it to be able to run the heat pump, well, hot water heater, fridge, deep freezer, TV & Internet.

My house has what I think to be a generator plug in the garage once I get the proper cable, is it as symple as plug it up? I am guessing I should turn off some of the breakers so not to over load the generator. Do i turn off the main power?

[STINEY]

Oh boy.....can of worms on this topic.

5500 MAY be enough, depending on the house and your habits.

Do you have a well pump? If so is it 220v?

The heat pump is surely 220v, does the generator have a 220v outlet? Not all do, especially in the lower ratings.

Turning off main breakers and backfeeding the panel from an outlet will work, BUT the utilities will have a cow if they see it done.

For my money, a main disconnect (like a big knife switch) and a dedicated breaker to feed the panel from a generator that is large enough is a economical way to do things. This will draw flames from the sparkies though, there has to be a physical interlock to prevent backfeeding the grid accidentally, and written procedure doesn't count. Has to be physically "impossible".

That said, I've always kept plenty of long extension cords on hand for my 5000watt generator. Plenty of grunt to run the furnace, fridge, freezer, 110v cistern pump (we don't bother with the 220v well pump in an outage) and some lights.

Now that we have Geothermal, that whole deal is out the window. Gotta come up with something different to cover the heating bases.

[SuperBuickGuy]

they'll have a cow because even if you switch off, you're not completely disconnected from the transmission lines... even if you don't care that you could kill a utility worker (they should know better, but there's some dumb ones out there) - you can burn your generator to the ground if something is wired incorrectly and it backfeeds (or worse, burn your house down).

I run my house on a 5500 watt generator - but I have gas-fired heat, so the load really isn't that large.


someday, I'll run my generator on dual fuel - both natural gas and gasoline....

[Aircooled]

You can always buy a big enough generator, but keep in mind how much fuel you want to buy/store/burn to keep some of those loads running. Size also depends upon what you are preparing for (winter storms, hurricanes or general poor reliability) and whether fuel will be available for purchase during your emergency. Too many people in the Gulf Coast spend $$'s buying a generator big enough to run their central A/C after a hurricane, and then find out the hard way that 20 gallons of gas isn't near enough to cover them until power is restored.

[STINEY]

Bingo, on both counts.


If you have natural gas availability, its crazy NOT to buy a generator that runs on it. Gas goes bad, diesel setups are expensive, propane is a good option IF you already have a BIG tank of it sitting around.

I just want to keep the heat on if we get another blizzard like the one in '78. I was a kid then, but I distinctly remember the large-by-huge amount of cold that we lived with for 2 weeks.

With my fuel oil furnace, on a couple of occasions, I just pulled the wires from the main panel and hooked them to an extension cord. Presto, heat.

That trick isn't going to work now though. The Geothermal uses 3 220 breakers all by itself.

Someone in town with a natural gas furnace could get by easily with a little Honda camping generator, natural gas furnace uses very little electric.

[Russell]

Most of the time in my area power is lost due to ice storms breaking trees taking power lines down. I have well pump I would think its 220v. Being able to have running water lets me stay in my home. Running the heat pump would be nice, but space heater in the room we are using would do. I have a 7 week old, an if Momma aint happy....

Dont really want to back feed on the grid that sounds bad. So you are saying even with the main power breaker turned off the house is still connected to the grid? or it is just not dummy proof?

I am not sure what the house has, I think there is a outlet intended to pug the generator in but I don't remember seeing a Large Disconnect. I will take pictures tonight.

[Beagle]

I run an A/C on a 4000w HF generator at the lake. Also used it to block heat one time. lol. It actually loaded up a little when I plugged in the heater. They use a lot of $ for gasoline, iirc, I'm about .33 to .5 gallons an hour depending on if the A/C ever cycles. If I were getting one tied to the house, I would look at Natural Gas. They make multi fuel kits that I've been interested in, there's a bunch of information on that from any search engine.

I'm kinda sorry I didn't step up to a 13hp or larger size, but getting the 6.5 hp model in and out of the truck bed is a nut tightening experience for me already. If I were trying to run my house A/C I would plan on something LARGER. Chinesium Watts don't work out the same as Reality in the USA watts for some reason. We've seen a load kill the "30"+ Amp generator, like starting a 10a air conditioner under pressure when it's good and hot outside.

[Russell]

far as I know there is no NG on our street if that was the case I would be looking for a reason to ditch my heat pump. It BLOWS (cold air) I have a propane stove and a small tank.

[DanStokes]

Our HF sometimes has Generac 13.5 KW units at about $3K IIRC. They don't always have them - I suspect they are available when they can get a shipping container of them for cheap. They will run on natural gas or convert to propane and include the correct disconnect box to keep the power company happy (and safe). Now that I have the big ol' propane tank for the shop heater I want to go that way but as usual we have to wait for money to show up (it does from time to time). That's the way I'd go - they kick on automatically when the power goes out and it's plenty big enough to run my little world.

Our next door neighbor has a similar unit (I forget the brand) and I'm hoping he'll let us toss an extension cord over the fence if the next disaster hits before we get a unit in and running.


Dan

[Beagle]

13.5 kW would run my house... 5500 is a hairdryer and a microwave away from stalling. If you have women, this WILL happen.

No offense meant, but I can't tell you how many times I've heard "I forgot" in my years.

The automatic start feature is very nice... I looked into remote starts last year, still on the "someday" list.

[STINEY]

Doht! Forgot the microwave........

Notice I never mentioned hot water? Suck it up ladies!

[Whelk]

Dont really want to back feed on the grid that sounds bad. So you are saying even with the main power breaker turned off the house is still connected to the grid? or it is just not dummy proof?

What you want is a transfer switch. This isolates the house from the grid and keeps you from electrifying outside lines. It should be installed by an electrician with building permits pulled. It's a liability issue as well as a safety issue. If you already have one one, I'd recommend having it inspected just to be sure it's right.

[Huskinhano]

I'm an electrician. Funny you posted this. I had CE classes this weekend to renew my license and one of the units was on generators. Aircooled made an excellent point about getting fuel to run your generator. You need a transfer switch to switch between your generator and utility. It's pretty straight forward. It's a sub panel that gets it's power from a breaker in the main panel. You move circuits from the main panel to the new sub panel's breakers. In the sub panel, there is going to be a bar that slides between two breakers in order to have one or the other on at one time. One is the feed from the generator and one is the feed from the main. You can't have both on at the same and disconnects the main so you don't back feed to the utility. Superbuick made appoint about electrocuting a utility worker which is a possibility but more then likely you'd trip the breaker on the generator since you'd be trying to power the neighborhood. If did some sort of redneck hook up and did backfeed the utility and the utility came back on, you'd be on the loosing end of a dangerous situation. One of the courses was on safety and the videos were pretty graphic! One was of a person actually getting electrocuted, it was NOT pretty. When you have a short circuit, depending on transformer impeadence and how close you are to it, you could be facing over 60,000 amps. It only takes about a quarter of one cycle or about .017 of a second for all hell to break loose. You'll be facing 35,000*F

A generator set doesn't have the ompf to handle the inrush of current when large motors start. They also may not have the line frequency control either. Some of the more sophisticated units will monitor line frequency and can tell when heavy loads come on and shed them as needed. Rule of thumb, the inrush amperage is about ten times that of full load amps.

They are noisy and will piss of your neighbors unless you run a line to their house. This is temporary power, keep that in mind. What do you absolutely need? Well pump, yes or you can run it only to fill 5 gallon jugs intermittently. I have a 5 KVA unit that runs my whole house. I don't have a well pump, heat pump or central air in my NJ house. My PA house does have a well and electric heat but does have a coal stove which I use to heat the house for the most part. I have a 5 KVA unit there as well.

Natural gas units. Sounds like a good idea but what kind of gas service do you have? The gas meter may not be big enough to feed it! The gas lines by me in NJ are low pressure. I have a 1" line going to the house. With more and more people installing natural gas generators on old gas infra structure, you might find yourself with not enough or no gas to run your generator. In the course, they pointed out a town close to me where the local ambulance corp installed a natural gas generator and sucked the gas out of the low pressure line for a seven block radius! They had to install a big propane tank with security cameras.

I think if I installed a bigger unit, I would run it on propane. Oh yeah, get a generator with copper winding in it's stator vs aluminum.

[milner351]

this is one of the places where I sucked it up and went "all in" we have a kohler / eaton 17kw 32hp vtwin natural gas auto back up generator. We don't have to be home - it senses a power outage and takes over - when the grid comes back up - it senses it and shuts down.
Is it the cheapest option?
no
Is it the easiest to install option?
no
Is it the most peace of mind option available?
yes.

we were without power for several days over a 4th of july weekend a few years back- that was the end of the "extension cord shuffle" for me - thinking about the vacations in the winter when we wouldn't be home and our house would surely freeze.

look seriously at the auto back up options. If you're going to stay where you are for a long time (10 years?) getting natural gas may pay for itself not only in peace of mind but also in resale value.

[Schtauffer]

I use a 6500 welder/generator. It's enough to run the hot water heater and well pump, fridge and lights and furnace. But if I want to run the stove/oven, I gots to make sure to turn off the water heater and well pump-- it caint run them all at once.