Stand by generators

[nckennedy]

Hi Guys,
Just realized recently that we do not have a back generator in the event of storm or whatever that might take down power lines for a couple of days.
We have several freezers for our beef and broiler business, an electric fence and the usual household appliances, etc.
How big a unit would be practical for our situation? Not sure either of the style! PTO powered, separate diesel engine, or propane.
Any Ideas you would care to share would be much appreciated.
Craig

 

[ETpilot]

First thing you should probably do is do a load analysis. These would be the things you must run. Total the watts and this will better allow you to size the generator. I have a miller welder/generator 8000watts. I only run a refridgerator, some lights, tv and well water pump. In summer a window unit AC. This works for me. Not long ago I purchased a HF 8700 watt generator. It is largest they sell not sure if I posted correct wattage. I have used it once during a power failure this past summer. It was good to have that window AC.

 

[grsthegreat]

freezers and refrigerators dont take too much power in themselves. depends on the number of units. Ive had 3,000 sq. ft.
houses run all lights, a freezer and refer, gas fired furnace and gas fired water heaters run on 5,000 watt generators. Now if you need electric heaters, electric water heater and well pumps, the loads rise dramatically.

As stated earlier you need to do a load calc. There are sites online that take you step by step thru the process... or get ahold of an electrician.

 

[GManBart]

Diesel is great, but very $. PTO gives you a lot of bang for the buck, but can be cumbersome, and at a time when you might need the tracorto clear debris, etc.

I went with a stand-alone natural gas/propane Generac with automatic tansfer switch (20Kw) and it has been awesome. The longest it's run has been slightly over 24hrs, but that alone made it worthwhile. We frequently can't tell when it's running (not that loud, and you get sed to it quickly), and not having to decide what will, and won't, get power is a big plus. We had two electricians do a load analysis, that roughly matched what I came up with, and they both said we could get by with 17Kw. I thought it was silly not to spend another $400 for the biggest air-cooled unit. That size runs around $4400 or so, and figure maybe $2k to install it unless you have an unusual setup like we did (gas line, and breaker panel on opposite sides of the house, 75' away).

You may want to do a search, there are a few huge generator threads already.

 

[econometrics]

2x on the 20KW Generac standby with automatic transfer here.

I thought I would save the money and just use a portable 5000W generator and roll it up whenever the power went out. But we had the means to bite off the true standby, so we did.

Just had a 1000 gallon propane tank installed, so we will have standby power for a good long while if the power ever goes out for an extended period of time.

I had thought about doing the PTO power, but for my wife's sake, I just went with what will be lost comfortable for her. I didn't want to be out of town on biz, have the power go out and her have to go out, fire up the tractor, hook up the PTO genny, and then hook it to the house - all for what could only be 30 min of power loss.

 

[s219]

If you want the generator to last a long time, go with a water cooled unit (and then think about what fuel makes sense, whether diesel, or NG/propane). The air-cooled units cost about half as much, but have a much shorter lifespan.

 

[TerryR]

If you have propane available with a large tank, it can be a great solution. No need to worry about fuel spoiling or getting out during stormy weather for more. We have a 1000 gal tank because our propane supplier didn't want to have to deal with our driveway in bad weather, so have a great supply for the generator during the winter months when outages are most likely around here.

Terry

 

[David_Kb7uns]

20kw Generac with 200amp load shedding switch, at less then 80 hours a year average it will still take awhile to wear it out, change oil on schedule and adjust the valves, they just upgraded the warranty to 5 years so they must have good confidence in them.

When shopping I could buy 2 20kw air cooled for the price of a diesel by itself or the 22kw liquid cooled Generac with switch

David Kb7uns

 

[coobie]

Stand-alone 17kw Generac propane model here also.Been 4 years installed without any problems.Keep oil changed every 40-50 hours with 5W-30 full syn.oil adjusted valves.I paid $4,650 installed.Like others have stated get a load study done.

 

[Monster5601]

I went with a stand-alone natural gas/propane Generac with automatic tansfer switch (20Kw) and it has been awesome. The longest it's run has been slightly over 24hrs, but that alone made it worthwhile.

Here is another very satisfied Generac owner. I have the 14 kW whole home with automatic transfer switch running on natural gas. When we lose power it can sometimes last two weeks or a few days, the Generac just does its job.

I am more likely to gas starve the generator than to over-load it, even with an electric kitchen. We live rural with septic, well, gas heat and electric kitchen.

 

[Recoveryhill]

In the Islands we are subject to catastrophic failure of the electrical grid due to hurricane damage and suffer from frequent failures of the municipal power due to grid, mechanical and operational errors. Keep in mind that none of us can depend on other utilities, like on the continent, to provide power when our generation capacity is down.

Stand-by generators are required.

For larger commercial and very large residential sites, diesel generator packages with automatic transfer switches are the norm. There has been a trend (more money than brains) for smaller residential users to install diesel packages with too much capacity. It is bad for equipment to run a generator at say, 30% of load. A minimum of 60% or more should be achieved.

The best, most economical solution for residential and small commercial sites is a gasoline powered unit in the range of 5 to 10 kW and a manual transfer switch that provides load shedding and powers essential services. Based on years of experience with these units, Honda GX powered gensets are the only way to go. They are fueled and treated with Stabil and most are run monthly out of need, or exercised monthly as is recommended. I have run a 13 HP GX coupled to a 6.5 kW generator for going on 8 years and have accumulated just shy of 1,000 hours. I change the oil and fuel filter annually, keep it covered and done. Choke, one pull and it starts, every time. I power refrigeration in my main kitchen and in a guest apartment, water pump, hot water heater, outlets in living room (s) and kitchen (s) and lights everywhere but bedrooms with 6,500 Watts.

No desire to stoke any arguments but around here Kohlers, Briggs and no-name engines such as those in Generacs are not preferred, only Honda Commercial engines. Automatic transfer is simply not necessary for residences and 10 Kw should be sufficient for most homes unless you use electric heat or need to provide power to devices that use very large amounts of current.

 

[savageactor7]

After deliberating a long time we settled on LP because of fuel storage issues and scrambling for fuel in emergencies.

Of all the advice I got the most valued was from the old timer that advised getting the smallest generator needed to serve our needs in an emergency situation...the result being that it would run the longest before needing refueling.

Pretty sure we have a 250 gal LP tank but since we heat with wood it can last a long time generating power...esp if I shut it off during the night when we're sleeping.

We wanted a generator that could out last another Labor day micro-burst or ice storm that left the are powerless for a week 10 days or so.

 

[coobie]

In the Islands we are subject to catastrophic failure of the electrical grid due to hurricane damage and suffer from frequent failures of the municipal power due to grid, mechanical and operational errors. Keep in mind that none of us can depend on other utilities, like on the continent, to provide power when our generation capacity is down.

Stand-by generators are required.

For larger commercial and very large residential sites, diesel generator packages with automatic transfer switches are the norm. There has been a trend (more money than brains) for smaller residential users to install diesel packages with too much capacity. It is bad for equipment to run a generator at say, 30% of load. A minimum of 60% or more should be achieved.

The best, most economical solution for residential and small commercial sites is a gasoline powered unit in the range of 5 to 10 kW and a manual transfer switch that provides load shedding and powers essential services. Based on years of experience with these units, Honda GX powered gensets are the only way to go. They are fueled and treated with Stabil and most are run monthly out of need, or exercised monthly as is recommended. I have run a 13 HP GX coupled to a 6.5 kW generator for going on 8 years and have accumulated just shy of 1,000 hours. I change the oil and fuel filter annually, keep it covered and done. Choke, one pull and it starts, every time. I power refrigeration in my main kitchen and in a guest apartment, water pump, hot water heater, outlets in living room (s) and kitchen (s) and lights everywhere but bedrooms with 6,500 Watts.

No desire to stoke any arguments but around here Kohlers, Briggs and no-name engines such as those in Generacs are not preferred, only Honda Commercial engines. Automatic transfer is simply not necessary for residences and 10 Kw should be sufficient for most homes unless you use electric heat or need to provide power to devices that use very large amounts of current.

Question not trying to be a smart *** but if there is no power at the gas station how are you going to get your fuel?How much gas do you keep on hand?I also burn wood pellets for heat and have a 500 gal. propane tank that I fill once a year.I agree with Honda engines as I have a 2000 watt Honda generator and most of my small equipment have Honda engines also.

 

[RalphVa]

We've a 12.5kw Isuzu generator from Central Maine Diesel. It's been in service for a little over one year. Diesel consumption for running 15 minutes every 2 weeks and once for 4 or 5 hours when power was off was 2.5 gallons (14.8 hours). It has a 60 gallon belly tank that I also use as makeup to my tractor. It does the whole house, but with 6 loads on load management from a Gen-Tran transfer switch 200 amp panel.

Before this, we had a 4kw gasoline unit that handled all our frigs, freezers, family room, kitchen and master bedroom. Had to turn everything off to run the well pump, but it would stay pressurized for quite a long period. Had it for about 5 years. It run off a manual transfer switch panel that the previous owner had in place from a propane generator that he removed before selling us the house.

I didn't want propane because I've worked with this material for 31 years. If we had natural gas to the house, it would be a no brainer to put in a natural gas generator. Much safer than propane. The propane suppliers wanted to install about a 200 gallon tank. Needs to be underground to reduce chances of a lightning strike, which won't blow up the tank but will blow up the supply line.

You should compute your overall yearly power usage (just divide your yearly kwh by (365 * 24, hours in a year)). In our case, it averages out to only a little over 1 kw. Two "whole house" suppliers wanted to put in about a 30-40 kw diesel generator without load management. It would be sitting there loafing away most of the time and would likely go into wet stacking and carbon up the injection nozzles.

Ralph

 

[Recoveryhill]

Question not trying to be a smart *** but if there is no power at the gas station how are you going to get your fuel?How much gas do you keep on hand?I also burn wood pellets for heat and have a 500 gal. propane tank that I fill once a year.I agree with Honda engines as I have a 2000 watt Honda generator and most of my small equipment have Honda engines also.

Good question, easy answer. The "gas" station is powered by a diesel genset and there are a couple of mobile operators here that refill these commercial units, for a price.

Second question: The fuel tank on the generator holds around five gallons. During hurricane season I keep four five gallon fuel containers on hand, treated with Stabil. During our "winter" I bleed that quantity down using the fuel for grass cutting equipment. During an extended outage I start the generator around 5:00AM and run for three or four hours, start it again around dusk and run until I go to bed, usually around 9:00PM for a total run time of around 8 hours consuming 5 gallons of fuel. Regardless of storm havoc, I can always get out and refill containers within a couple of days so my 25 gallon capacity is plenty. Thankfully the majority of use for the stand-by unit is to cover the frequent outages that usually last no more than two to three hours and always occur at the worst possible time.

 

[Recoveryhill]

You should compute your overall yearly power usage (just divide your yearly kwh by (365 * 24, hours in a year)). In our case, it averages out to only a little over 1 kw. Two "whole house" suppliers wanted to put in about a 30-40 kw diesel generator without load management. It would be sitting there loafing away most of the time and would likely go into wet stacking and carbon up the injection nozzles.

Ralph

Sounds like you have a nice set-up. I've lusted after a 12 kW Kubota genset from Maine Power but just can't justify the cost. For me, even in a challenging environment, the 6.5 kW Honda floats my boat.

Tell me about over capacity! People make the same mistake here and if it's bad for the engine, it's even worse for the generator. You need to be using at least 60% of the capacity or trouble awaits.

 

[Turbys_1700]

I have a 10K generator under the back porch full of fuel for emergencies...
As some have said, the lower cost route is to purchase a 5K-10K stand alone unit...
I can get 12 hours of run time with 6 gallons of fuel...
It the area you are in has more outages then a whole house system may be justified but the cost can be expensive...
We lost power for two hours last Monday morning and @ 8 degrees I was so preoccupied with heating the house I completely forgot the spring house...
Needless to say the water froze trough my own negligence since my unit will power my pump and spring house light fixture...
If I would have had my head working correctly the generator would have run the light bulb in the spring house and I would have not been without water for two days of freezing temperatures...
I do have my generator wired into my panel box so I can energize the whole house if need be...
Just have to turn the appropriate breakers off to not overload...
Very convenient...

 

[Recoveryhill]

I do have my generator wired into my panel box so I can energize the whole house if need be...
Just have to turn the appropriate breakers off to not overload...
Very convenient...

I assume you have a transfer switch which isolates the grid from your generator supplied power. Back feeding into the grid can kill an unsuspecting lineman trying to restore power. With a transfer switch you pre-determine which circuits/loads you supply when you switch to the generator, all your permanent house breakers are off......

 

[expedoman55]

We have a 3800 sq ft house that is heated by propane in upstate NY ( yes the polar dip really hurt) I have a 15KW Generac propane genset. with automatic transfer switch I designed and built and installed myself in 04 that also filters the AC from the generator and cleans it.

In the north east flooding of 06 and 11 we have run on for over a week. We have a separate 250 gal laydown tank and have only used 30% of tank max.. at one point we had 12 families staying with us and several RVs hooked up as we are rural and no one had water except us because of the generator.

Seems to run well and work.. I would love 20kw liquid cooled but limited funds and generator availability was an issue when we did the job thus why I built my own transfer and monitoring system.

 

[GrandLakeGAR]

Interesting perspective from the Caribbean. I wonder if the preference for gasoline and diesel generators there is due to a lack of availability and higher cost of natural gas and propane in the islands? Maybe for outages of a few hours a portable is ok but in this rural area we are subject to extended power loss due to ice storms and tornados. I put up with the aggravation of portables for years but after the Joplin tornado I installed a 20kva Generac with a designated 500 gal propane tank. Totally satisfied and the "no name engine" made by Generac by the way has run non stop for several days on occasion. All automatic operation, powers the house, shop and well, should have done it sooner.