Home generator... - PeachParts Mercedes-Benz Forum

MercFan · #1 09-11-2010, 10:48 AM

I know generators have been discussed here but I can't find a good recommendation for a home backup generator (emergencies only). I'd like to have a portable diesel one in case there is a real emergency so we can run few things on and off. What would be a recommended minimum size: 6kW, 7.5kW, etc?

How about one of these?
http://denver.craigslist.org/tls/1941221080.html

http://denver.craigslist.org/tls/1913700971.html

Don't know what to look for in a good one - continuous duty cycle, size, etc...

James

Matt L · #2 09-11-2010, 11:20 AM

A diesel generator would be nice, but we got a gasoline generator from Sears during a power outage in '06. The thing ran for a full week and burned a bunch of gasoline, but it got the job done. I think it was 3600W continuous, but I would have to look to be sure.

How much you need depends on you. We turned most of the circuits off to ensure that we wouldn't overload the generator, and had to manage the power to run heavy consumers like the coffee maker (e.g., unplug the refrigerator until the coffee was made).

retmil46 · #3 09-11-2010, 12:11 PM

If you want to be able to run most anything in the house besides a heat pump, something on the order of 10 to 12 KW would be what you'd need. Especially if you have an electric water heater and your own water well, electric stove, and want to be able to take a shower and cook food.

In particular for a water heater, pump, and stove, you'll need a generator that can put out 220/240 volts at some level of amperage. A 12 KW generator should be able to supply 220 volts/50 amps if it's set up to provide full capacity thru the 220 volt connection.

Not the best way to decide, but better than nothing - look inside the breaker panel for your house. Note the voltage and amperage ratings for the breakers of the stuff that you'd absolutely want to be able to run. Note the amperage rating of the largest breaker, and/or add together the amperage rating of the breakers of items that would have to be running at the same time - ie, water pump and electric water heater. Then look for a generator which has a voltage and amperage output that can handle this load.

Usually, the items in question won't pull anywhere close to what the breakers are rated for once running, but using the above method you won't be caught short either, and also gives some headroom for starting surge current as well.

More exact method would be to look at the electrical rating labels on each of the appliances you want to run and add them up - ie, 5 lamps with 100 watt bulbs, water heater rated at 3000 KW off of 220 volts, water pump that pulls 10 amps off of 220 volts, etc.

Matt L · #4 09-11-2010, 12:52 PM

Our little unit also has a higher "starting wattage" rating, only good for a few seconds. It didn't have trouble running the refrigerator and furnace fan at the same time on separate legs. We were also running a few computers and a TV set, but those were fairly minor consumers, considering.

10fords · #5 09-11-2010, 01:05 PM

Quote:

Originally Posted by MercFan

I know generators have been discussed here but I can't find a good recommendation for a home backup generator (emergencies only). I'd like to have a portable diesel one in case there is a real emergency so we can run few things on and off. What would be a recommended minimum size: 6kW, 7.5kW, etc?

How about one of these?
http://denver.craigslist.org/tls/1941221080.html

http://denver.craigslist.org/tls/1913700971.html

Don't know what to look for in a good one - continuous duty cycle, size, etc...

James

First you have to figure what you want to be able to run from the generator. Then you can size it accordingly. Look for the continuous duty rating as some of the cheaper generators will try to fool you by listing their surge rating. PM me if you want with some details and I can tell you what you will want to look for.

kknudson · #6 09-11-2010, 02:11 PM

Do a basic tally of what you need to run first.

But I have a 5k normal / 6k peak and it allows me to run most of what I need.
Yes there is that caution of not running certain things together, but with a little bit of care that is easily taken care of.

We do not have a well, electric heat etc.

But we do have several sump pumps. main basement, addition, lift station (interior and exterior), fish tanks (lots) and computers (more than the average).

Cycle through the sumps, one has a battery backup, one hardly runs, don't use the basement bathroom or do laundry, turn off the lights in the fish tanks, cycle through the computers as most that are needed are on UPSs.

Keep this in mind.
Unless you live in an area that has a history of a lot of EXTENDED (6hrs +) outages these monster generators that will support your entire house are really overkill.

Our neighborhood was ok up until the year I setup the generator just regular outages (a lot, but short lived), the year (probably 6 months) before I put it in we had 8 or 10 12ish hour outages, since that time with the exception of a 3 day outages this summer (we were on vacation) I doubt if I've used it more than 10 or 15 hours total for 10 years.
In fact several years I have really only run it to warm it up before changing the oil.

So the 1000 bucks I invested seems worthwile, versus the 3 to 5k + for a big fancy setup and my generator is portable.
I got the wheel kit, spark arrestor, and cover.

Stretch · #7 09-11-2010, 02:48 PM

Diesel and even hydrogen generators are common power solutions for computer server rooms. Whilst some of these solutions will be a bit big for your home requirements perhaps you can get some tips for what you might need from the plentiful smaller solutions... just an idea for data gathering - I know 'cos it is an "IT solution" it will be expensive.

Another idea might be solar / wind energy solutions and loads of submarine batteries!

strelnik · #8 09-11-2010, 03:34 PM

Quote:

Originally Posted by Whiskeydan

Anything bigger than 6KW better have wheels.
I have a 5KW cont and it is a (serious) two man lift.

I'd love to have a Lister.
http://www.youtube.com/watch?v=qVT-dNWt3I8

I'd love to have one too, preferably one of the slower-moving stationary models, maybe about 60 rpm?

Ah, but where to find them?

I could use mine to operate the heat, a water pump and an electric toilet

kerry · #9 09-11-2010, 06:01 PM

My Wanderlodge has a 12.5KW diesel generator run by a Perkins 4-108. Very common on Bluebirds.

Skid Row Joe · #10 09-11-2010, 06:06 PM

Quote:

Originally Posted by MercFan

I know generators have been discussed here but I can't find a good recommendation for a home backup generator (emergencies only). I'd like to have a portable diesel one in case there is a real emergency so we can run few things on and off. What would be a recommended minimum size: 6kW, 7.5kW, etc?

Don't know what to look for in a good one - continuous duty cycle, size, etc...

James

To get a proper service diesel-powered generator capable of running your "whole house," you'd better fasten your seat belt AND have deep pockets when you see what one goes for!

elchivito · #11 09-12-2010, 12:47 AM

I can recommend this one:

http://www.bsapowersolutions.com/pages/EM12-Generator.php

Our house isn't terribly large and is solar heated and cooled, so freezers, fridges etc. are our biggest consumers. Power outages, frequent out here, are no longer an issue. Automatic start works flawlessly. Propane.

retmil46 · #12 09-12-2010, 10:07 AM

Agreed, if you try to get a generator big enough to run EVERYTHING in the house AT THE SAME TIME, even a gasoline powered generator will run you multiples of four figures.

Do your homework first, and figure out the maximum power you need to run just the ESSENTIALS that you ABSOLUTELY NEED - ie, lights, ability to keep warm, ability to cook food, ability to take a shower/flush the toilet/have running water.

Once you know the maximum amount of power you would need at any one time to do this, then you can shop around for a generator with a continuous load rating to handle it.

Oft times, the normal places that sell generators such as Northern Tool, Home Depot, etc, will get in several sizeable generators that were used by a contractor for a specific job, then returned to the distributor. They're often refurbished and sold as used at a substantial discount. Several years ago, I picked up a 12 KW continuous load wheeled unit at Home Depot that was used by a contractor and refurbished - normaly one of these units cost in the range of $2500 or better, I picked up this refurbished one for $1500.

rscurtis · #13 09-12-2010, 08:06 PM

I would avoid any of the "imported" 3600 RPM diesel sets. While they may have decent sound attenuation, you're generally on your own after purchase. A nice Yanmar YDG set is expensive, and still 3600 RPM. I have a unit assembled by Global Power Products (a division of Mack Boring and Parts) using a Newage alternator and a 1 litre Yanmar engine. It is 7000 watts and 1800 RPM. I have it in a separate garage and cannot hear it in the house, and neither can any of my neighbors. It is capable of auto start/stop, but I don't have that feature enabled. I'll try to get several pictures tomorrow for those who may be interested. Trouble is, as I've bought better and better generators, I've needed them less and less.

Hatterasguy · #14 09-12-2010, 08:38 PM

I have a Mitsubishi 5800 for around the job site, its not that loud. Around the house you could run what you need off it, fridge, some lights etc. Pricey though at $1,500 but its meant to be used quite a bit, I have only about 400 hours on it.

What kills most generators is sitting, you need to run whatever you buy at least an hour a month. Change the oil once a year and put Stabil in the gas, if not it won't work when you need it.

Skid Row Joe · #15 09-13-2010, 12:05 AM

Generators of any kind should be run RELIGIOUSLY, for a minumum of 20 - 30 minutes, under 75% load factor ONCE A MONTH.

My diesel coach's generator is one bad-azz and pricey Onan.....and it gets run as prescribed.