If you're considering a generator for your home

[ATCclears]

I posted this on an aviation forum after someone asked for input. I'm reposting here in case any of you have ever considered a generator for your home. Please ask if any additional questions.

Peter


So the three big things you'll need:
- generator
- generator-transformer box (aka gentran)
- thick 220v cable from generator to gentran
- certified electrician to install the gentran, and make you a cable

I was into mine for say $1500 back in 1997. You could probably get into same for $2000-$2500 today with an install by a certified electrician.

If you choke on the price, ask yourself what it might cost to replace the food each time in the fridge and freezer. Add to that any costs if you went to a hotel, and then of course the intangible value of simply continuing most of your current way of life without too much interruption.

First, what can you power?
- Yes to a gas furnace. You're just running the blower and the temp sensor. Probably no on an electric furnace.
- Probably no to an electric hot-water tank (if gas, no electricity required)
- Yes to a microwave
- Yes to a 120v fridge
- Yes to a 120v freezer
- Yes to TV, computers, lights
- No to an electric oven or cooktop.
- No to an electric dryer
- Probably yes to a sump pump (if you have one, and if it's 120v)

You'll need to assess what can be powered by the generator. There are limits. You can't have everything running at once since the generator will have a finite output of electricity. For example, the microwave call pull up to 1000 watts for a large, hi-power model. The good news is that everything doesn't run at once, but I do try to keep the total load down on my generator so as not to damage it.

Generator. Many options. You can probably get a good one at Costco for $800. Two key considerations are total continuous watts available, and then do you go with manual/pull start or electric start. Mine is 5000 watts continuous and 6250 surge/temporary watts. I would recommend at least 5000 watts for a typical home. My generator is also a pull start. The pull start on a 10hp engine is fine for me but difficult for my wife. A generator with an engine larger than 10hp may be harder to pull start.

Gentran. This controllers what circuits get powered by the generator, and keeps the electricity within your house. Buy a unit/panel with at least 10 switches. 1 switch = 1 circuit breaker in your house. Also, you might get one with a watt meter for each side of switches since this gives you an indication of how many watts you're pulling at that point in time. Each Gentran switch tends to have 3 positions: Line (typical power), Off, and Gen (your generator). So in real use you flip the individual switch from Line to Gen and *tada* that circuit is now getting juice from the generator. It's that easy. It's also safe since your generator is not providing power back out on the line, energizing the transformer, and potentially jolting/killing a lineman upstream from you.

Wiring in the Gentran. Work with the electrician to determine what circuits you want to connect to the Gentran (you might even pre-identify and mark the circuit breakers if you're paying the electrician by the hour). The electrician can take it from there.

Cable. The electrician can make you an appropriate cable with 220v connectors on each end. Ensure that the cable is long enough so that the generator is not running right next to your house. Mine is 50 feet long and I think it cost me $5/ft at the time (it is almost 3/4" thick). I keep my generator in the garage to reduce exposure to the elements when it is idle, but when it's running I've had it out un-sheltered in the wind/rain/snow and never had a problem.

Maintenance on the generator. This is critical. Don't let it sit for a year or two and assume it will magically start. I pull my generator out 3-4x a year and run it for 20min. I also change the oil every Fall regardless. If you have an electric starter then you'll want to keep an eye on the battery on the generator. I've had the same $500 generator since 1997 and it's never failed us. Most outages have been a few hours, but in 2006 there was a bad windstorm and we were on the generator for perhaps 30 hours. I also tend to run the generator for 20min in advance of a large storm.

Spare fuel. Every generator is different. Mine burns approx 5 gallons of gas every 8-10 hours. I try to keep about 20 gallons of fuel in the shed, and use/replenish via the generator, lawn tractor, etc. such that the fuel isn't too old.

Suggestion. Buy the generator at Costco (or other), and then perhaps the Gentran at Home Depot if they're still offering a referral service to certified electricians.

Read More

 

[PBinWA]

You can power a well pump, hot water heater, two fridges, a freezer, and a few other low draw electric appliances off a decent quality 5500/8500watt generator. I did it this week for a few hours.

Otherwise, excellent advice. I'm not a big fan of the last transfer switch I bought at Home Depot. After about 5 years half the switches/circuits no longer work. I need to replace it with something else.

 

[Bon Sauvage]

ATCclears, are there generators and GENERATORS or are they all about the same? In other words are there some makes to avoid? If you had the $$ what would you buy?

 

[Capn Jack]

All great information!!

A note of caution...Never plug, or unplug with the generator running...
Always check that the ends of the cord from the generator to the transfer switch
are secure. If the cord comes loose and you loose neutral, you can apply 220v to all circuits.
Mine vibrated loose and I took out five clocks, four light ballasts and my pellet stove control board.

 

[ATCclears]

ogre, I don't have an answer there. I bought a $500 Generac from Costco in 1997 and I still use it today. I could not afford to spend $3000 on a Honda generator (with an electric start) at that time. Prices have changed since then, and I think there are more manufacturers in the market. I have not seen a brand assessment in Consumer Reports or similar.

I think what matters more is taking care of the generator. If you can, keep it in a semi-heated location when not in use. Run it a few times a year. Change the oil every Fall.

If Costco offers a two-year warranty on the generator then that might be a preferred purchase option.

Peter

 

[deen_ad]

Our motorhome sits right next to the house, it has an 8Kw (continuous output) liquid cooled diesel engine generator. At full output it takes .72 GPH and it's hooked to a 150 gallon fuel tank. So far I've never needed to use it for a power outage as they're few and far between in the 25 years we've lived in this house.
According to the manufacturer it should be run for an hour with half load every month. This keeps moisture out of the stator, which is the usual cause of problems although a gas unit can have varnish problems in the card too.

 

[ATCclears]

A quick update. The correct terminology for what I called the gentran unit seems to be "generator transfer switch". This should help you find it faster if you're searching via Google, Home Depot, or other.

Peter

 

[HenryJ]

I think you meant to say "Transfer" , not transformer.

Gentran, Reliance, EmerGen, Briggs&Stratton, etc. are all brand names. Those may be helpful in a search. The switch can be automatic or manually operated. It is referred to as a Generator transfer switch, Power transfer switch, Manual transfer switch.

I did my set-up really inexpensively.

My 4000w generator is adequate to power our house. We are on a well and all heating is done via natural gas. No power needed for room heat or cooking. All lighting is high efficiency.
My generator was a real bargain. $161 new. The cord I made myself for $50. The EmerGen manual transfer switch $128 new on ebay.

The transfer switch came with instructions and a video. In my state I am allowed to do my own home wiring, "to code", so I did my own install. It really is no more difficult than installing circuit breakers.



I do not power the whole house. Just the circuits that are needed and will not overwhelm the generator. This has worked great for about four years so far. My total investment $340

 

[Sling Blade]

Thanks for all the great information!!

 

[PBinWA]

That EmerGen Transfer Switch looks a lot like mine but I think I have a higher rated version. It worked great for a few years but it seems each time I use it another circuit has crapped out with no discernible reason as to why.

In short, I don't recommend that brand.

 

[HenryJ]

...it seems each time I use it another circuit has crapped out with no discernible reason as to why...

I have had good luck with mine and the other two that I helped friends install.

What fails? I am curious as to what exactly the problems were on yours? It would be nice to know what to look out for.

If the circuit breakers fail , they can be replaced. The switches are just double throw and can also be replaced or contacts cleaned. Pretty simple really.
If too much amperage is being drawn they are designed to protect themselves. Each of these on mine are 15 amps and can power no more than the 15 amp breaker to which they are attached. Two connected together offer 30 amp 220 for my well.

Each circuit is not usually "rated" higher. There are panels with more circuits to spread the load over a greater number though. A greater number of circuits would require a larger generator.

Many times household circuits get taxed and over used. If the load is too great it needs to be divided.

 

[PBinWA]

I had one switch just crap out and it won't move anymore. The other two circuits stopped working altogether when I went to use it this week but I haven't had time to look inside. I'm pretty sure nothing is getting overloaded as I tested it pretty extensively when it was installed. The 15 amp circuits only powers a few circuits in my basement which at most are running a fridge and a freezer but I have them on separate circuits. The two 30 amp circuits are for the hot water heater and the well pump.

I'll look at it eventually but for something so simple it kind of sucks to have it fail the few times you need it to work. But it was cheap and I think I got what I paid for.

 

[HenryJ]

I had one switch just crap out and it won't move anymore.

Very good to know! Thank you.
Perhaps a little dielectric silicone and some contact cleaning might fix it up again? I might watch for some replacement parts to stash.
I'll keep an eye on mine. I have HAD to use it half a dozen times over the years and it has always worked. My wife and son practice using it once a year. That puts us under a dozen deployments probably.
Really hard to say if another brand will be any better. I see many similarities in some of the others. Reliance appears to be much the same.
Everything seems to be a roll of the dice today. You do the best you can with what you find.

One thing for sure, you are ahead of the game if you have a transfer switch installed. Even in the event of a switch failure, you can "wire nut" a solution together. Much better than being limited to extension cords and a couple outlets on a generator.

BTW, you can send me yours when you replace it. Better than hauling it to the dump and I'll keep the spare parts

 

[PBinWA]

BTW, you can send me yours when you replace it. Better than hauling it to the dump and I'll keep the spare parts

I'll try to remember this thread.

When the first switch died I looked at replacing it but the whole thing is one component and the individual switches didn't look to be serviceable. That was a year or so ago when it happened so I've kind of forgotten exactly what happened. Needless to say I wasn't that impressed with the quality of construction at the time.

I may have just got a lemon.

I can always bubba my generator by backfeeding (I have a whole house cut-off) but that isn't too kosher. However, in a bind it's good to know how to survive.

 

[PBinWA]

If I had room in my panel I would use this:

Generator InterLock Kit



It seems like the simplest method to use.

 

[HenryJ]

It does look like a very simple solution that could be "home made" too. However the generator REALLY needs to be matched to the panels requirements to prevent overloading it. I do like having meters to use for monitoring demand. The addition of some gauges in such an installation would be helpful. That is a large step in complicating the KISS of that lock out though.

One thing that system may not incorporate is a way to have a few circuits remain connected to the grid. Ours leaves several low priority circuits grid connected. We leave a light on as an indicator that power has been restored and we can make the switch back.

 

[CharonPDX]

If you have a Prius (or another Toyota-style hybrid, like from Ford, Nissan, or Lexus,) you can use your car as an emergency generator, with about $200 in parts: PriUPS. (Or $2000-$4000 to turn it into a full-blown house-connected generator.)

As soon as my Prius' battery warranty expired, I added a secondary higher-capacity plug-in battery (which now gives me about 20 miles electric-only driving range, for pennies in electrical cost,) and the simple generator connection; and will be doing the house-connection bit when we build a garage later this year.