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roger wiegand
03-06-2018, 8:57 AM
The recent storms are providing yet more evidence that our electrical infrastructure is crumbling; we have multiple friends across the northeast who are without power for 3-4 days now, for some not for the first time this year. Others have gone without power for weeks at a time in recent years. This has me re-thinking adding a backup generator. I've resisted the notion largely because the ones that have been near to us are irritatingly loud, both in actual use and during their periodic "exercise" runs.

Are any of you aware of any particularly quiet units? This would be permanently installed with automatic switching, powered with natural gas. I need to do a load calculation, but I'd try to keep it on the small side. I wouldn't plan on running AC or the electric dryer, just the furnace, fridge, lights, computer, and perhaps a table saw :D. The specs I've looked at so far are short on noise information. I'm not sure why they should have to be louder than, say, an idling car.

Robert Engel
03-06-2018, 9:19 AM
I have a friend with a Generac unit that is surprisingly quiet. Can't remember the model but it has a propane powered engine.

Jim Becker
03-06-2018, 9:24 AM
None of them are truly "quiet" but where you put them and how you baffle sound can make a difference. Mine was running from 4pm on Friday through 6pm on Sunday due to storm-related outages, largely caused by trees hitting infrastructure. It clearly was running given the sound level of the thing! There is no comparison to an "idling car" because the engine in the generator is running more-or-less at full throttle. That all said, I have zero regrets on making the investment. We have no water and no septic if power is out.

You're not going to save a ton of money by being selective with the circuits a unit will run as the actual cost difference between a whole house unit of 20-22kv and one of lesser capacity, once you include installation costs, isn't significant. My 22kv Generac cost $9K installed turn-key. It runs both of our HVAC systems as well as everything else with no issues regardless of season. Note, I do not have the feed to the shop on the generator since that's a separate feed from the meter. Ours uses natural gas (the only utility from the street we have other than coms and electric) and the whole house automatic transfer switch came with the unit standard. A whole house transfer switch is significantly less complex to install than doing only specific circuits which reduces installations costs...that helps narrow the cost gap that I already mentioned.

Bill Dufour
03-06-2018, 9:38 AM
Do they make them water cooled? that is the easiest way to reduce noise levels.
Bill D

James Cheever
03-06-2018, 10:10 AM
Another vote for a natural gas, Generac 22KW whole house generator. Running the entire house is the way to go; really simplifies the install. If I remember correctly, our turnkey cost was just at $10K, including the gas run and hookup. We also have an ABT switch that kicks it on with a power loss and unloads and shuts it down once power is restored. The system also does an automatic test run each Saturday to ensure the system is operating normally. From insiode the house we can hear it, but only as a low rumble. If you are talking or listening to music or TV, it doesn't interfere at all.

Mac McQuinn
03-06-2018, 10:40 AM
I just did the yearly maintenance yesterday on my 2006 Honda EB5000 Contractor generator and at idle, it's quiet enough to talk over standing next to it. At load when the auto kicks up the speed, it's certainly louder although not nearly as loud as most on the market. I'm into quite equipment, If there was something sufficiently quieter out there , I'd certainly give it a look.
Mac

Rod Sheridan
03-06-2018, 11:00 AM
Noise level is inversely related to price.

That was sort of a tongue in cheek comment, although it's true.

At work we have a 1,500 Kw generator that you can barely hear run at 30 feet. Critical grade silencing is available for a price.

Perhaps contact your local Caterpillar dealer if you want to spend the money to get a quiet set. I'm sure there are other manufacturers available locally, I just don't who else would be in your area.........Regards, Rod.

roger wiegand
03-06-2018, 12:25 PM
Thanks, I was definitely planning on a whole house system, not just selected circuits. I was just saying we'd choose not to run the AC or dryer if the power were down. Generacs do seem to come in air cooled and systems with coolant and a radiator. I'll have to see if I can compare them. Appreciate the comments.

Marc Jeske
03-06-2018, 12:38 PM
Can't you reduce size and price by reducing total load by just turning off individual unneeded branch ckt breakers?

If it starts automatically with "Too much" stuff on, the main breaker may trip.. you then go turn off the uneeded breakers, and re start gen?

I do NOT know if this is ok, but makes sense to me as a "Free" NO cost way to "seperate" ckts when the house panel is fed.

Marc

Kev Williams
03-06-2018, 5:16 PM
If you're anywhere near where an earthquake may happen (I am), give serious consideration to NOT getting a natural gas unit. At least with gas or propane, you CAN go get some, even if 100 or more miles away. If the NG stops, your genny is useless...

Jim Becker
03-06-2018, 5:42 PM
Can't you reduce size and price by reducing total load by just turning off individual unneeded branch ckt breakers?

If it starts automatically with "Too much" stuff on, the main breaker may trip.. you then go turn off the uneeded breakers, and re start gen?

I do NOT know if this is ok, but makes sense to me as a "Free" NO cost way to "seperate" ckts when the house panel is fed.

Marc

As I noted, in the current market, there's not a whole lot of saving to be had with a smaller unit and "selective" circuits" because the installation becomes more costly. And to meet code, you must either use a whole-house transfer switch for the "whole schmegeggie" or use a transfer switch and panel designed to isolate specific circuits. In no instance should there be a startup issue if the system is installed correctly.

Mike Cutler
03-06-2018, 6:43 PM
Roger

Go whole house backup if that is feasible. If propane and natural gas are reliable in your area during power outages this is a good option. It will be about $10K-$12K to have it ready to go.
I elected to go with gasoline, because of the unpredictability of propane delivery in my area in the event of a power outage. Natural gas is not an option for me.
I have the Generac 17,500 "portable" unit. At 500lbs. full of gas, "portable" is kind of stretching it. I replaced a little 4000watt Coleman Powermate with it. I got tired of sequencing loads after losing power last October for 4 days. My wife got really tired of it! and that's how we ended up with the Generac. :eek:
It is loud, but I can accommodate that due to my lot size and proximity to neighbors. If I wanted to, I could get a Zombie Box enclosure and really quiet it down. It comes in through and external inlet power box and is breaker protected. There is a mechanical interlock in the panel to prevent the main and the generator breaker from being able to be physically closed at the same time.

Whatever you do, please install it per code.
Look at Zombie Box if you need an enclosure. They're specifically designed for generators.

Scott T Smith
03-06-2018, 9:07 PM
Noise is directly related to the operating RPM. Large, commercial generators typically operate at 1750 rpm, and are less noisy than the 3,600 rpm smaller units.

If you need less than 7KW, the Honda EU series are very quiet. We have one as a backup generator for my wife’s mobile veterinary hospitals (they have onboard diesel Generators).

If you need more than 7KW, Kohler has some very quiet enclosures available for their 25KW plus units.

I have some Onan 10KC RV diesel generators that are pretty quiet.

Hands down though, the most quiet generator that I ever did not hear was a “movie tone” model by MQ Power. We actually stood right next to a 50KW unit and the only way that we knew it was running was to put our hands over the exhaust pipe. I kid you not - it was that quiet.

Bill Dufour
03-06-2018, 9:51 PM
earlier I said water cooled is quieter but I forgot to ad that means the pump seal can leak or rust shut. For a seldom used thing like that a gravity flow cooling system would be ideal. They probably do not make them like that because it costs more and makes a bigger unit. Yanmar diesel tractors used to use a gravity cooling system so I bet thy made generator sets that were gravity cooled.
My father told me model T fords could run up to about 35mph all day long if the pump/fan belt broke. They had enough radiator height to allow some thermo siphoning.
Bill D

dennis thompson
03-07-2018, 8:00 AM
None of them are truly "quiet" but where you put them and how you baffle sound can make a difference. Mine was running from 4pm on Friday through 6pm on Sunday due to storm-related outages, largely caused by trees hitting infrastructure. It clearly was running given the sound level of the thing! There is no comparison to an "idling car" because the engine in the generator is running more-or-less at full throttle. That all said, I have zero regrets on making the investment. We have no water and no septic if power is out.

You're not going to save a ton of money by being selective with the circuits a unit will run as the actual cost difference between a whole house unit of 20-22kv and one of lesser capacity, once you include installation costs, isn't significant. My 22kv Generac cost $9K installed turn-key. It runs both of our HVAC systems as well as everything else with no issues regardless of season. Note, I do not have the feed to the shop on the generator since that's a separate feed from the meter. Ours uses natural gas (the only utility from the street we have other than coms and electric) and the whole house automatic transfer switch came with the unit standard. A whole house transfer switch is significantly less complex to install than doing only specific circuits which reduces installations costs...that helps narrow the cost gap that I already mentioned.

Jim
I have an electrician coming this morning to give me an estimate for a 20-22 kw generator. He does both Generac and Kohler. I assume you did some research before deciding on the Generac. I would appreciate your insight into your choice and any suggestions you might have on what accessories I should have installed. I'm in Monmouth county NJ, not that far from you.
Thanks

roger wiegand
03-07-2018, 9:25 AM
Earthquakes are few and far between here in eastern MA. Snowstorms (1 ft due today), windstorms, and falling trees are not. Several towns closed all of their roads in this last nor'easter, so getting to the gas station for fuel would have been problematic there. Nat gas seems to be the best and most reliable fuel source here.

I have a 5kw Onan "Quiet Diesel" liquid cooled generator on my organ trailer. It's made for RVs and allegedly rated for campground use, but I'd hate like heck to be trying to sleep next to that thing running! Getting it to fire up when it's cold out is a touch-and-go thing--OK if it catches the first time, but the battery doesn't usually give you a second chance. I'd hate to have to be jump starting my backup generator out in the storm!

I don't do construction that's not to code and with the required permits. In our town that means both a licensed electrician and plumber for this job, an expensive install.

Jim Becker
03-07-2018, 9:41 AM
Jim
I have an electrician coming this morning to give me an estimate for a 20-22 kw generator. He does both Generac and Kohler. I assume you did some research before deciding on the Generac. I would appreciate your insight into your choice and any suggestions you might have on what accessories I should have installed. I'm in Monmouth county NJ, not that far from you.
Thanks

I actually had my choice of either Generac or Kohler with the fixed price turn-key deal I had for a 20-22Kv unit at $8999 from my vendor. (Colonial Generators) I chose the Generac because of a 10 yr parts and labor warranty promotion that was coincidentally available at the time. Performance wise, they were equivalent units. Kohler might have been "slightly" quieter in dB, but given the nature of these things, the very long warranty coverage was compelling. There's not much in the way of accessories necessary as this class/size of generator generally comes with a 200 amp automatic transfer switch. The farm where we board out horse has a Kohler and they are very pleased with it...'doesn't look much different than the Generac other than the color. :)

The single thing I'd really like more control of with this kind of thing is how the exhaust is handled. They all typically send it out the end of the unit and that can play havoc with landscaping. I have a temporary "baffle" setup to redirect it upward until I can move a specimen plant that's a bit to close and is suffering for it. The really big generators have a more directional exhaust setup not unlike a truck or tractor. If I could exhaust "up" it would be a really nice thing and it might even help with noise abatement. Once I move that plant, I may put a short, removable fence around the three exposed sides (the fourth is the 18" thick stone wall of our home) to be more courteous to our neighbor around sound level.

https://qaepwq.sn2.livefilestore.com/y4mZCSr5P9H2LNhowbUU8IMRaQsqT7BD5ZQUe2EqColTEidlyk q0J3fQ9xM9NKDAafsghvSOYNqk7S08q4MZxBL5Km146ZJSKZIY H7ke4QENRqecd02CJFagbdVn7gHqcEaL-mmmSfj7NvimE_f_W1H65iltUB6DeUViDsOrGuV0C18zjyiYKh-BgeHBXL8wUhfTKSSD7x9tUc0KbE2_DvlfA?width=660&height=660&cropmode=none

Robert LaPlaca
03-07-2018, 2:16 PM
We have the same backup generator (Generac 22KW). As Jim stated, you need to be mindful of the location of the exhaust. Our landscape architect was concerned how the generator would look from our house, he had three small hollies planted in from of the generator to screen the view from the house, one long power outage cooked the closest of the hollies.

We we live in a urban neighborhood, many of the home have backup generators.. The generator sounds like a typical large landscaping lawn mower when running. The 22 KW unit is the largest air (oil cooled) Generac unit, any larger you get into water cooled generators.

dennis thompson
03-07-2018, 4:34 PM
I actually had my choice of either Generac or Kohler with the fixed price turn-key deal I had for a 20-22Kv unit at $8999 from my vendor. (Colonial Generators) I chose the Generac because of a 10 yr parts and labor warranty promotion that was coincidentally available at the time. Performance wise, they were equivalent units. Kohler might have been "slightly" quieter in dB, but given the nature of these things, the very long warranty coverage was compelling. There's not much in the way of accessories necessary as this class/size of generator generally comes with a 200 amp automatic transfer switch. The farm where we board out horse has a Kohler and they are very pleased with it...'doesn't look much different than the Generac other than the color. :)

The single thing I'd really like more control of with this kind of thing is how the exhaust is handled. They all typically send it out the end of the unit and that can play havoc with landscaping. I have a temporary "baffle" setup to redirect it upward until I can move a specimen plant that's a bit to close and is suffering for it. The really big generators have a more directional exhaust setup not unlike a truck or tractor. If I could exhaust "up" it would be a really nice thing and it might even help with noise abatement. Once I move that plant, I may put a short, removable fence around the three exposed sides (the fourth is the 18" thick stone wall of our home) to be more courteous to our neighbor around sound level.

https://qaepwq.sn2.livefilestore.com/y4mZCSr5P9H2LNhowbUU8IMRaQsqT7BD5ZQUe2EqColTEidlyk q0J3fQ9xM9NKDAafsghvSOYNqk7S08q4MZxBL5Km146ZJSKZIY H7ke4QENRqecd02CJFagbdVn7gHqcEaL-mmmSfj7NvimE_f_W1H65iltUB6DeUViDsOrGuV0C18zjyiYKh-BgeHBXL8wUhfTKSSD7x9tUc0KbE2_DvlfA?width=660&height=660&cropmode=none
Jim
Thanks for the information. The electrician came this morning and,while he does both Generac and Kohler, he prefers Kohler. He said he has fewer repairs with the Kohlers. I plan to get two more estimates and see what they say about Generac vs Kohler.

Jim Becker
03-07-2018, 8:06 PM
Sounds like a plan, Dennis!

BTW, "Matilda" is back to work today...12" of heavy wet snow and it apparently caused something else to fall on a line somewhere and cut power to 2000 properties in our immediate area. You would think that after this past weekend, there wouldn't be anything left to fall on the wires. LOL

Brian Brown
03-07-2018, 8:29 PM
I really don't know much about generators other than I would like one, and this is a great informational thread. However, the most important thing i have learned is Jim Beckers term


"whole schmegeggie"

I like it. No, I love it! I am going to use it as often as possible. Who knew that I would learn new vocabulary terms on this forum. It is my new favorite term. Whole schmegeggie, Whole schmegeggie,Whole schmegeggie. :):):):D Now if I could just learn to spell it. :eek:

Dave Cav
03-10-2018, 2:21 PM
We had an 8KW Kohler propane unit at our previous house. It wasn't set up to run the entire house but it would run the furnace, most of the lights, the fridge and freezer via selective transfer breakers without any problems. We were in a rural area in the Pacific Northwest and had frequent power outages due to the abundance of trees and overhead power lines. The generator was in an insulated steel enclosure and very quiet. I never had any trouble with it for the seven or eight years we had it.

I'll be installing a 12 or 14KW whole house system in our new home currently under construction. All Kohler. Since there are only two of us and the range, heating and water heat is gas it should be more than adequate. It'll be connected to the natural gas mains but I plan to explore a propane backup in the future.

I also have one of the newer HF Predator 3KW inverter generators for general utility use. It's worked fine so far and is VERY quiet.

Don Morris
03-11-2018, 8:47 PM
We have the whole house 20K Generac. Yes it's noisy when going, but after we went through the Derecho Storm that hit this DC area a few years back and left us without electricity for a week, LOML said "Let's look real close at getting one". The once a week testing only goes on for a few minutes. When the whole neighborhood loses electricity, and all the generators kick in, especially the gas operated ones, yours won't sound so loud. Ask me we know as we had a couple going until they ran out of their own supply of gas and couldn't get gas at the local gas station during the Derecho. The gas station lost electricity too, and couldn't pump gas. Agree with the others that the whole house is worth the extra, for peace of mind. The exhaust we took care of by putting a stone garden there. In the stone garden we placed a small stone buddha in front of some decorative stone I got from a local stone and brick yard. It works reasonably well. Also, I thought that the Natural Gas Generac we got could be converted to Propane by just throwing a lever which changed the size of the burner flame. Similar to Outdoor Grills, they can be changed from NG to Propane with relative ease.

Additionally, I understand that Real Estate agents are looking at whole house generators much more positively than they did a few years ago. Certainly their presence continues to increase in our neighborhood.

Matt Meiser
03-12-2018, 2:36 PM
I did a 17KW Generac at my old house. It was essentially right outside the master bedroom window and we could sleep with it running as long as the windows were closed. My mom has the same generator and there's a foot-thick solid brick wall between it and the living room (1860 house) and I know its running from the monitoring system texts before she does. Here we have an older 16KW that's on the other side of a 2x6 wall from my office. I hear it in here but I've asked a few people how load it is on the phone when it starts and they don't hear it.

Brian Elfert
03-17-2018, 7:40 AM
If you're anywhere near where an earthquake may happen (I am), give serious consideration to NOT getting a natural gas unit. At least with gas or propane, you CAN go get some, even if 100 or more miles away. If the NG stops, your genny is useless...

I figure if the disaster is big enough to lose both electric and natural gas service that I would probably want to leave the house. My house is heated with natural gas so I wouldn't have heat even with a generator. I have a natural gas generator.

I also have a diesel generator in my converted bus and 130 gallons of diesel I could use, but it is wired for 120 volt although it wouldn't take much to convert back to 240 volt.

Brian Elfert
03-17-2018, 7:47 AM
I had a Kohler backup generator at my last house. (This house too.) One time I was gone for the weekend and I stepped out of the car and noticed a little bit of noise. I investigated and the generator was running as the power was out. It was barely audible. The garage door had opened as normal so I didn't realize the power was out.

The generator at my current house sticks out like a sore thumb when you pull up to the house. I talked to the realtor who sold me the house and he didn't think it would turn people off if I sold the house. I plan to put up fencing to block the generator if/when I sell. Placing the generator elsewhere would have cost at least $1,000 more to run the gas and electric to it. It was a DIY project that cost me less than $4,000 so another $1,000 was huge.

Matt Meiser
03-17-2018, 12:39 PM
Brian, we did that with the heat pump at our old house. They couldn't put the heat pump where the AC was because the darn thing was almost 5' tall including the "snow legs." It had to go at the end of the house where it looked terrible. We had a fence company put in 6' PVC picket fence on two sides leaving about 3' clearance. Since the pickets had space between then airflow was no issue. It turned out so nice my mom did the same. Since the generator is much shorter you could buy materials at a big box store easily if you wanted to DIY in plastic. I did a DIY one around the AC on the shop with some reclaimed cypress, also super easy.

Mike Cutler
03-17-2018, 6:23 PM
Brian

For reasons I still don't understand, a few years back, during Sandy,we lost power for 8 days. So did the town, and the natural gas plant in town. Without electricity it wasn't capable of distributing gas.
It may have changed now because all of the businesses were required to only use natural gas, back up generators.
The town got sued by Home Depot,Walmart, Target , etc. For not being able to supply the gas for their backup power. Hopefully the situation has been resolved. I'm sure a lot of folks were counting on NG to power their backup generators and were stuck.

dennis thompson
03-18-2018, 7:34 AM
I had a Kohler backup generator at my last house. (This house too.) One time I was gone for the weekend and I stepped out of the car and noticed a little bit of noise. I investigated and the generator was running as the power was out. It was barely audible. The garage door had opened as normal so I didn't realize the power was out.

The generator at my current house sticks out like a sore thumb when you pull up to the house. I talked to the realtor who sold me the house and he didn't think it would turn people off if I sold the house. I plan to put up fencing to block the generator if/when I sell. Placing the generator elsewhere would have cost at least $1,000 more to run the gas and electric to it. It was a DIY project that cost me less than $4,000 so another $1,000 was huge.

Brian
While the realtor who sold you the house said it wouldn't turn people off if you sold the house ,your comment that it sticks out like a sore thumb seems to indicate to me its position could be a pretty big negative to the houses curb appeal.
I am currently looking getting a generator and plan to place it in our back yard so it does not stick out like a sore thumb. Yes it is an extra $1,000 but I think it's worth it and to be honest your "sore thumb" comment convinces me its the right decision.
Thanks for your input.

roger wiegand
03-18-2018, 8:05 AM
Fortunately I have a place to put one that is at a far corner of the house, reasonably out of sight, and close to both existing gas and the main electric panel.

I called a couple of places back when I first posted, before our most recent nor'easter. Only one guy called back so far, and he told me he had 360 calls on his desk to return! I'm not too surprised I haven't heard from the others yet.

Brian Elfert
03-18-2018, 10:23 AM
Brian
While the realtor who sold you the house said it wouldn't turn people off if you sold the house ,your comment that it sticks out like a sore thumb seems to indicate to me its position could be a pretty big negative to the houses curb appeal.
I am currently looking getting a generator and plan to place it in our back yard so it does not stick out like a sore thumb. Yes it is an extra $1,000 but I think it's worth it and to be honest your "sore thumb" comment convinces me its the right decision.


What I didn't mention is a big part of the reason the realtor thought it was okay to place it there is because the electric meter, air conditioner, gas meter, and a window well are there too. There is so much utility stuff there that the generator doesn't really stick out as much as it might without all that other stuff. Trust me, I spent a lot of time looking at alternate locations for the generator. Due to the design of the house it would be very difficult to run electrical and gas through the basement to the other side of the house. I seriously looked at putting the generator by my detached garage, but I can't recall why I scrapped that idea.

If it comes time to sell I will do some landscaping to block the view of the generator and other stuff. Nobody can see this stuff from the street as the house is well back from the street and has trees blocking the view.

When the house was built in 1980 little thought was given to designing things to keep the utilities out of view. The house was built on the cheap so they probably didn't want to pay extra to place the electric meter out of sight on the back or other side of the house. The house had electric baseboard heat and no central air when I bought it so only an electric meter at the time. I added central air and natural gas service. It made sense to place this stuff on that side of the house because that is where utility room is.

Brandon SPEAKS
03-18-2018, 8:35 PM
Another thought. I have a cabin that is off grid that has both solar and a generac generator. As part of the solar system it has a battery bank that will power the house for about 3 days (and if I recall correctly the batteries cost about $1,800, yours might be more depending on power needs but we do have all the normal stuff a house would have). In the winter when panels are snow covered or its been rainy for awhile I can run the generator for about 90 minutes and fully charge the batteries.

With this solution it is only briefly loud and provides an extended period of power.

All in I paid about $6k for the generator and $8k or 9$k for the solar. At the time a solution with the generator, battery bank, and other required equipment but without solar panels would have run a total of about $9k if I recall.

Larry Edgerton
08-10-2018, 6:30 AM
Roger, you may want to ask an electrician on this point, but recently here they passed a code that the backup has to have enough power to carry the whole house load. In other words if everything you own is turned on at one time the generator has to be able to carry that load.

Coding for the lowest common denominator placing an unnecessary burden on those of meager means that are smart enough to run just what they need. Will lead to more jury-rigged homeowner hookups. Because I have a 400 amp service I would have had to have a way bigger unit than I want to fuel, so I have the well on a switchable plug and the furnaces on plugs so I can change them out. Would rather have had an automatic transfer unit but was not going to buy that size generator. Now that my house has a final inspection I may change it over .

Wade Lippman
08-10-2018, 2:46 PM
Roger, you may want to ask an electrician on this point, but recently here they passed a code that the backup has to have enough power to carry the whole house load. In other words if everything you own is turned on at one time the generator has to be able to carry that load.


You have to be mistaken. Your electrical service can't power everything turned on at once; why would a generator have to?
More importantly; I get enough NG to my house to run my 8kw generator and my furnace; but no more. Yet your code says I have to run a generator 25x as large? It is essentially outlawing "whole house" generators; but maybe that's the intent.

Perry Hilbert Jr
08-10-2018, 4:00 PM
My neighbor grew up on an isolated island off the coast of Greece. No body there had the grid. Everybody had ways to get around that. His house here was wired for 120, but he had a bank of batteries in a basement closet and a small turbine on the roof and a couple solar panels. His heat came from a wood stove and a set of fans that drew the heat to the upper floors. everything in the house operated on 12 volts. His light bulbs in the ceiling fixtures, coffee maker, the electric griddle, fridge, freezer, blender, tv, (Oven was propane) etc. He also claimed he was good for three days before the batteries needed a boost. But he would run a heavy 12 vote extension cord to his work truck and let the truck run for 30 minutes and the batteries would be good for a few more days. He eventually did hook up to the grid, but only when he wanted a large screen tv for his granddaughter to watch when she visited.

Brian Elfert
08-10-2018, 11:46 PM
You have to be mistaken. Your electrical service can't power everything turned on at once; why would a generator have to?
More importantly; I get enough NG to my house to run my 8kw generator and my furnace; but no more. Yet your code says I have to run a generator 25x as large? It is essentially outlawing "whole house" generators; but maybe that's the intent.

The NEC code now requires you do one of three things when installing an automatic standby generator: 1. Buy a generator large enough to power everything in the house. 2. Put everything you want to power with generator on a sub panel and only power that stuff (as long as generator can power it all). 3. Install a transfer switch with load shed capabilities so load can be removed if generator is near capacity.

There are several ways to do this that don't require sizing generator to power everything in the house. Load shed is probably one of the more popular options right now.

Marc Jeske
08-10-2018, 11:59 PM
Dang.... WTF ???

If I was.... with a LIMITED budget want to get a backup Gen...I would forgo any "Hardwiring", auto xfer stuff, etc.

We DO live in the "East TX Piney Woods" Dying and wind blown Pine trees are dumping overhead lines on a regular basis.

I would simply get a Honda or other "Quality" or other smallish Gen, ( NOT from HF) enough to run AC (I'm in hottt TX), a Hotplate,toaster oven, my Comp, internet, and Dish, a few lights, ...and just go out and plug in those things.

BUT... That is ALL due to a limited budget in my case.

If the $ are available to carry a full house, , Carry on.

Marc

Charlie Velasquez
08-11-2018, 8:15 AM
The NEC code now requires you do one of three things when installing an automatic standby generator: 1. Buy a generator large enough to power everything in the house. 2. Put everything you want to power with generator on a sub panel and only power that stuff (as long as generator can power it all). 3. Install a transfer switch with load shed capabilities so load can be removed if generator is near capacity.

Mmmmm.... code refers to automatic standby only??
I am assuming, then, that service panel interlocks are still code compliant?

Jason Roehl
08-11-2018, 8:57 AM
Dang.... WTF ???

If I was.... with a LIMITED budget want to get a backup Gen...I would forgo any "Hardwiring", auto xfer stuff, etc.

We DO live in the "East TX Piney Woods" Dying and wind blown Pine trees are dumping overhead lines on a regular basis.

I would simply get a Honda or other "Quality" or other smallish Gen, ( NOT from HF) enough to run AC (I'm in hottt TX), a Hotplate,toaster oven, my Comp, internet, and Dish, a few lights, ...and just go out and plug in those things.

BUT... That is ALL due to a limited budget in my case.

If the $ are available to carry a full house, , Carry on.

Marc

I don't know how your A/C is sized down there in TX, but here in IN, I have a 1900 s.f. bi-level house, with an A/C that's on a 35A breaker. At 240V, that's over 8 KW, just for the outdoor unit--that doesn't get it blown around in the house. I'd rather swelter a bit and keep my two fridges and large chest freezer running, since the one fridge holds the beer.

Mike Cutler
08-11-2018, 9:15 AM
Mmmmm.... code refers to automatic standby only??
I am assuming, then, that service panel interlocks are still code compliant?

Charlie
No, the code addresses portables also.
Beginning in 2010 and finalizing in 2012, portable generators have been designed differently. Basically, if the generator is marketed for temporary power at a job site, to be OSHA Compliant, it has to have the neutral bonded to the frame. This is not desirable if you are trying to back feed a house, or smaller generator transfer panel. If you hook up a portable generator made in the past few years, to your house, you will have parallel return path, and potential, on the ground wire. This will at minimum give GFCI's fits.
You need to be able switch the neutral return from the main service panel. It's a lot more difficult to use a portable, code compliant, to power your house.
The service panel interlock you refer to does nothing to address the switching of neutral for a "newer" generator. This is a huge discussion point on many electrical forums. The days of back feeding the dryer, or stove receptacle, are kind of gone now. If you want to supply power to your house with a portable, somewhere there will be a three conductor disconnect to switch out that neutral.
Honda and Yamaha make larger "portable" generators with a "switchable" neutral to frame bond. One possibility.

Jim Becker
08-11-2018, 12:02 PM
I don't know how your A/C is sized down there in TX, but here in IN, I have a 1900 s.f. bi-level house, with an A/C that's on a 35A breaker. At 240V, that's over 8 KW, just for the outdoor unit--that doesn't get it blown around in the house. I'd rather swelter a bit and keep my two fridges and large chest freezer running, since the one fridge holds the beer.
Our 4200 sq ft home has two HVAC systems...no issues with that on our 22kv generator with auto-transfer. We have complete "normal" usage of everything with about a 10-15 second down time when the utility is lost.

Wade Lippman
08-11-2018, 3:07 PM
The NEC code now requires you do one of three things when installing an automatic standby generator: 1. Buy a generator large enough to power everything in the house. 2. Put everything you want to power with generator on a sub panel and only power that stuff (as long as generator can power it all). 3. Install a transfer switch with load shed capabilities so load can be removed if generator is near capacity.



Okay, #2 is the only method I have seen for whole house generators.

Wade Lippman
08-11-2018, 3:12 PM
I don't know how your A/C is sized down there in TX, but here in IN, I have a 1900 s.f. bi-level house, with an A/C that's on a 35A breaker. At 240V, that's over 8 KW, just for the outdoor unit--that doesn't get it blown around in the house. I'd rather swelter a bit and keep my two fridges and large chest freezer running, since the one fridge holds the beer.

I agree with you. I weathered two 8 day outages with a Honda 2kw that ran my ridge, furnace, freezer, TV and computer going. It was fine.

Now I am out in the country where outages are much more common, so I have a 8kw, but only because it was the smallest one I could find. Only thing I really added to the above is a portable AC.

Marc Jeske
08-11-2018, 3:13 PM
In my post, I was using my situation.. a compact small home w a 16kbtu AC through wall in main living area.

Enough to get by economically and simply... low budget bang for buck.

Marc

Brian Elfert
08-15-2018, 10:58 PM
Okay, #2 is the only method I have seen for whole house generators.

For an existing house it is often very difficult to add a sub panel so load shed is used instead. Most standby generator transfer switches now have load shed included or optional now. I was lucky and I was able to reroute selected circuits from the main panel to a sub panel. At the time in 2015 I was not aware of the new NEC requirements for automatic standby generators.

I have no idea how load is calculated for standby generators. They certainly can't assume every lighting and receptacle circuit is going to be maxed out.