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Discussion Starter · #1 ·
We have lost power again in my area (ice storm) and this is the last straw.


I have been eyeing a Generac Generator for a couple of years (liquid cooled model). They are not inexpensive so I was wondering how those of you that own them would rate them in terms of reliability and maintenance over the years.


I am looking at a 20 KW or 30 KW model. The 20 W will run my whole house as if there is no outage and 1 AC compressor. The 30 will that and run all my AC compressors.


Anyone here own one of these. These are fully automatic and require no user input for powering on. It runs on natural gas.


If we want to keep it somewhat on topic, I am sure I can run my power hungry theater on it..
 

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Generac, Kohler and some other manufacturers provide similar units. They can be useful at times. One situation to remember is, these units need to be run regularly in order to operate properly. Some of the units have timers, which can be set to automatically run the generator and swap over the residential loads.


A second possibility is to get a portable generator, have an electrician install the necessary interfacing equipment (disconnects, interlocks etc.) so that all you have to do is plug the generator into the interface and start the unit. This is a much cheaper method BTW.
 

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25kw natural gas generator minimum: specify a low RPM unit for quiet operation and a sound box


check local codes : I needed a variance and local code had a noise level spec which was impossible to meet: there are setbacks from the property line and clearances from the house in the codes: should be mounted on a concrete base


oversize the generator breaker panel so you can add additional loads


when your A/C compressor turns on, beware your audio system may kick out
 

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I actually sell and install Generac generators. In general I would recommend a 16 KW unit. This is the largest residential generator that they sell. The larger liquid cooled ones require more work to install and maintain. The 16 KW can come with an automatic transfer switch that will power any 16 circuits of your choosing. It can also be wired to power your whole home, although if you have a really large home, a whole house transfer switch is probably not a good idea. For Detroit, I wouldn't even put the AC units on it unless you often lose power in the Summer. In Buffalo, almost all of our outages are in the Winter months.
 

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Discussion Starter · #5 ·
Mark,


Good to know.


My city has a strict noise ordinance. 70 db from 25 ft away. THe Generac models (Quietsource) are rated from 70-72 db. I will ask my electrician about the low RPM - meaning I may have to go with a larger unit.


If it fails the noise test, I have to build a wall (brick, etc) to further dampen it and hide it with evergreens, etc.


My city requires 3 permits (noise, mechanical, electric). They are a real PITA.


Thanks for the advice.
 

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I think if you are in a region where severe weather can knock out the power it is a good idea. One person that I know installed a 30k gas powered set-up. The hurricane forced some people to rethink whether they need a generator. I only have a small one for back up power. I own a large spread of property north of New Orleans and am investigation both solar as well as generator power for it as I plan to build my retirement home there. I believe that high gas prices are going to do more than create cars with alternative power sources. Something that I have been watching for years is battery technology. My hope is that as car companies develope solution for cars, and off-shoot will be large batteries with great storage capacity that can serve as back-up power in such cases. Perhaps such batteries could be kept charged with trickle solar power. Does not help your current situation though. On another note, I have been watching such companies for awhile as good stock investment candidates. The company that figures out high tech battery storage is going to be a very profitable one.
 

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I have a fairly large house, with 9 tons of AC (5 + 4) and was going go just go the whole house route (35 or 40 kw), with 1000 gallon buried LP tank.......UNTIL i found out how much it would cost to run the damn thing for a week (Southern louisiana, huricane season).....


Check the generac data sheets on fuel usage (available online), they are hungry.


I beieve the quite models run around 1200-1600 rpm...and they have real mufflers..not noisy at all (sound like a honda civic)....


I would go with the 20ish Kw, automatic transfer and pick 1 ac unit and 1 section of the house (for me, kitchen/keeping/living/1 guest room/1 bathroom/ hotwater heater/ and the 5 ton unit). you dont even know the other side of the house is hot!



Quote:
Originally Posted by thebland /forum/post/0


Mark,


Good to know.


My city has a strict noise ordinance. 70 db from 25 ft away. THe Generac models (Quietsource) are rated from 70-72 db. I will ask my electrician about the low RPM - meaning I may have to go with a larger unit.


If it fails the noise test, I have to build a wall (brick, etc) to further dampen it and hide it with evergreens, etc.


My city requires 3 permits (noise, mechanical, electric). They are a real PITA.


Thanks for the advice.
 

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I'm glad someone mentioned this, I have been mulling over the idea of installing an LP unit in the new house, which is already going to have an LP tank... Thanks everyone for the info...
Quote:
Something that I have been watching for years is battery technology.

Bulldogger---do a Google search on "EEStor", if you haven't already. If they succeed in getting real product out, it's going to be revolutionary stuff. For example:

http://thefraserdomain.typepad.com/e..._ultracap.html
 

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...and for us people that live in earthquake country, propane might be a better way to go because of natural gas line breakage.
 

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Why not go with:


(1) a smaller unit (~10kW),

(2)a 5-10kW solar array,

(3) and a few of these puppies.

(4) A nice bank of deep cycle batteries will store the extra energy in order to supply nice clean energy when you need it.


This way, you'll lower your bills 24/7 AND be ready for emergency instead of paying a huge chuck of money for a system that is used maybe once a year.


Something "alternative" to think about.
 

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Hi



First. I doubt 20 KW can do anything for your house... unless you restrict yourself to not running AC, most appliances, etc. Keep in mind the following. Most electric motors draw sometimes up to 3 times their nominal output... Just think of the many electrical motors in the typical american house and also think of the heating elements... An electrical iron is usually a 1.5 KW energy devouring device... A microwave oven takes its 1.8 KW easy and a 100 gallons water heater often has 2 4,500 watts heating elements.... That is 9,000 watts just for the water heater. Of course it does not work all the time but when it does make sure this does not coincide with a few AC compressors starting or 2 people ironing or.. you get my point....

Adding these up will take you over 20 KW easy.


LP and Diesel generators would be the preferred way to go. Some do come in self contained form some of them can be rather silent. Good name with sterling reputation are (among others) ONAN , Kohler. They can come with is called in the industry an automatic Transfer switch wich starts them up when main power goes off and disconnects them from the house once commercial AC is restored. THe switching is rather fast but not fast enough for sensitive electronics not to be turned off or damaged sometimes if you do have that kind of problem a UPS could become a necessity, it keeps certain fragile or important things alive while the generator is spinning up to be up to the demand of the load.


Micahel, yes batteries are an option and we in Haiti and other countries use them to power our houses, some use the DC current but most people use a DC to AC inverter. Often the batteries charger (AC to DC rectifier) and the Inverter (DC to AC inverter) are housed in one box called an "Inverter". THe "Inverter" is usually a Battery charger, DC to AC Inverter and Transfer switch capable of controlling generators... Battery capacity is a function of the total load and of the autonomy required to put things in perspective. If you were to run a regular American house with all its equipment functioning as usual a bank of battery costing say $10,000 and taking the area of a one car garage will power it for, maybe 2 hours if that much.. So yes batteries can be used but you have to use different unless you curtail the use of energy devouring appliances.. No way you can run water heater on batteries for example ABSOLUTELY NO WAY.. Batteries can and are used in residential setting all over the world but a different strategy of home energy must be devised... more later..
 

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Discussion Starter · #12 ·
Frantz,


Running the AC is not what I am after. It is keeping warm and pipes from freezing.


You may be right about the size. My guy is coming out to size it.


We have 2 large refridgerators, wine fridge, 2 bar fridges, wine cellar AC unit. All total, I have 4 AC compressors for the home (just under 6000 sq ft). I wouldn't pay for a large enough unit to run all of them..but one would suffice.


I'll check out the other options you mentioned or a larger Generac. To be fair, my elctrician guesstimated over the phone - he has yet to come out and size things up...


Thanks!
 

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i have a Kohler 11RMY 11kw Natural Gas generator wired into my home electrical system. it was here when i purchased the home three years ago (the home is now 6 years old). at the time it seemed a bit of an extravigance......but recently it seemed to be the most important feature of the house.


i live in the mountains 30 miles east of Seattle on 4 1/3rd acres. we are at about 1100 ft elevation. the house is 5200 sq. ft. it uses radient floor heat so there is no heater fan to run but there are pumps for each branch of the heat. i do have a separate 1800 sq ft barn which has a heat pump but the generator does not power that.


i have a water feature with a big pump, a front gate, and a hot tub/spa (NG heated) all of which are powered by the generator. most of the house runs on the generator except the ovens in the Kitchen. my HT (in the house) is not powered by the generator but my other TV's are. i do have direct TV satellite for when the cable is down.


the generator turns on automatically 10 seconds after the power goes off and then shuts down automatically 30 seconds after the power comes back on. every friday morning at 10am the generator runs for 20 minutes as a test.


when i bought the home the generator had about 50 hours on it. up until a month ago it had about 120 hours on it. some from the power outages we do have for various reasons (mostly weather related) and the test runs.


on December 14th we had a '100 year' windstorm. basically the whole of western Washington was affected.....1.5 million people were without power for at least a day, about 800,000 were without power for 3-4 days.......and 125,000 were without power for over a week.


i had no power, cable tv or internet service for 8 days. you think that is no big deal but unless you go thru it.....it is hard to imagine how much you depend on electricity to live.


i was very lucky and here is why. guess what......gas stations run on electricity.....no electricity.....no gas. wide areas were without electricity and therefore people could not get gas. many people had generators but these people had to keep filling these gas tanks with a dwindling supply of gasoline. people were driving 50 miles to get gas for their generators. cars were dead oon the side of the road having run out of gas. the stations that had gas ran dry. kinda like a made-for-tv movie.


i had an uniterupptable supply of natural gas.


you cannot appreciate how essential my generator became to my comfort level.


another thing.....natural gas burns clean. my generator ran for eight straight days without stopping. on the 6th day i did shut it down for 5 minutes to check the oil. it had not used a drop and was perfectly clean.


this generator 'rocks'.
 

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one additional point.


at the auto dealership i manage we were without power for over 2 days. we have three generators but had never used them fo so long before. it turns out that the UPS's for our main computers and phone system were not compatible with the 'dirty' electrical output of our generators.


for the last three weeks we have been researching this issue and have figured it out. we are installing a 'gen-tran' system which will be a pre-wired panel we will easily and quickly be able to switch over to generator power and at least power our main computer and phone. we have also tested a 7500 watt Honda generator with an 'inverter' that does work with the UPS of our phone system and main computer. this generator lists for $4k. if you have some computer issues consider this approach.


i am learning waaaay more than i ever wanted to know about generators.


unfortunately the windstorm of a month ago left behind a very fragile power grid for the entire region. it will likely be 6 months to a year before we can feel that things are back where they were prior to the windstorm. we are seeing lots of flickers and short outages. so having a good generator solution has become essential around here.
 

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Did major research on these before my purchase. I went with a Cummins commercial unit after checking out Kohler. Kohler makes a nice product but their distribution system allows NC dealers ro sell them for thousands more than any other state in the union. Since they must be started at setup by an authorized dealer to validate warranty I rulesd out Kohler. Generac is more of a low end unit. Check the rpm of the engine and fuel consumption. They are available with an automatic exerciser that runs them for 10 minutes every few weeks.


A good electrician can also designate one panel as essential and move the circuits that you truly need to that panel. We have a 20kw unit that will run everything in the main part of our house for several weeks on a 1000 gallon lp tank.


This company sells by mail and they are one of the largest dealers in the US. Most dealers order from manufacturer when you place an order, he has millions in inventory. The recent rash of storms may have put even him behind. His web site is informative and he carries the major brands.
http://www.generatorjoe.net/product.asp?0=0&1=0&3=335
 

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I have the same Kohler 11RMY 11kw Natural Gas generator as Mike


a couple of years ago a substation transformer blew out and we were without power for 10 days in the summer: each day was over 100 degrees: the generator did me proud and kept one 3 ton A/C and essentials running without problem: we lived in the one air conditioned room (which happened to be my HT) the whole time


But every time the A/C compressor cycled on, my HT would drop out because of the voltage drop: I have UPS supplies that keep the PC and other loads running until the generator kicks in: UPS supplies draw a heavy load on a generator


I got a quote to install a larger generator but it would have been too big for the pad: that is why I suggested Jeff consider a 25kw unit minimum: knowing he has larger loads in his house: most folks install 25 kw units in large new houses in my area


fwiw: a neaby resident who is a day trader installed 2 high speed generators to prepare for Y2K: these things (I think they were 35 kw each) were screamers: they were so loud he only ran them as backup for the Y2K event (turns out they were not needed) and then had to remove them because of noise complaints: he dropped a bundle on that mistake
 

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Living in Miami, I know about generators.


We recently bought 15kw liquid propane Generac generator. It runs both air conditioning units ( 3 ton and 5 ton unit) as well as all the electrical inside. Things you cannot run are electric heaters, the oven, strong electric motors (like a circular saw or compressor) because they eat up a ton of juice and can pop a breaker.


If you can, go with a natural gas line straight from the city so you don't have to buy a tank. Mines needed a tank because my area does not have natural gas lines.


Last major outage we had a 400lb propane tank last 5 days (AC in the day, off at night)
 

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In Jan '03, after a "last straw" 3-day Dec. (a very cold one) power outage, I installed a 15KW Generac, running off a 1K gal propane tank. I picked it up at Home Depot (they loaded it in my horse trailer
), and installed everything myself except the propane hook-up and trenching/cables from generator to house. I bought the Generac dedicated transfer switch separately, since I had the builder install an aux. generator panel w/breakers when I built the house, so I didn't need the switching/breaker combo unit that comes w/the generator.


Has been 100% reliable, through probably at least 15 outages so far (3 days was probably the longest). Performs its automitic 15-min. exercise every week. Runs my HT gear (including PJ and Krell monoblocks) w/no detectable change in performance.


On the generator circuit:

all lites and most plugs

water heater

furnace

refrigerator

disposal

microwave

well pump

phone & alarm systems


Not on generator:

A/C

washer & dryer

dishwasher

trash compactor


If I were to do it again, I would at least research a larger unit, b/c the A/C would have been reeeeeeeally nice during a couple of mid-summer outages. But other than that, I would highly recommend the Generac.
 

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Quote:
Originally Posted by crackyflipside /forum/post/0


We recently bought 15kw liquid propane Generac generator. It runs both air conditioning units ( 3 ton and 5 ton unit) as well as all the electrical inside. Things you cannot run are electric heaters, the oven, strong electric motors (like a circular saw or compressor) because they eat up a ton of juice and can pop a breaker.

Re. "strong electric motors": if you allow for the motor's startup surge current in your total usage calculations, you can run them off the generator. Your A/C units have a huge surge for their motors. My well pump, which is on my generator circuit, runs at 6A @ 230V, and has a 15A surge (and it frequently cycles on and off).
 

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Jeff, email me [email protected] and I'll give you my generator installer. I am replacing my 25KW unit tomorrow with one that will be quieter (the noisy one came with the home, but won't pass a use permit db test). This will do my entire house including the 3 HVAC zones. Luckily, we have kept the noisy generator connected since we moved in last year and it kicked on twice this past 2 months, including 12 hours yesterday!


Mark
Quote:
Originally Posted by thebland /forum/post/0


We have lost power again in my area (ice storm) and this is the last straw.


I have been eyeing a Generac Generator for a couple of years (liquid cooled model). They are not inexpensive so I was wondering how those of you that own them would rate them in terms of reliability and maintenance over the years.


I am looking at a 20 KW or 30 KW model. The 20 W will run my whole house as if there is no outage and 1 AC compressor. The 30 will that and run all my AC compressors.


Anyone here own one of these. These are fully automatic and require no user input for powering on. It runs on natural gas.


If we want to keep it somewhat on topic, I am sure I can run my power hungry theater on it..
 
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