Let's Talk Backup Power!

Shop deals on ebay
SpartanEpoxies
Advertise with us
House Repair Talk

Help Support House Repair Talk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
K

Krich

Well-Known Member
Joined
Jun 12, 2017
Messages
384
Reaction score
98
OK, so I was thinking of having something for power in the event my house experiences long term power outage or even really, really long term power outage... as in end of the world kinda stuff (you never know these days what's gonna happen ya know - such as power grid failure)

I have a 200 gallon propane tank sitting out in the yard, so for short term power outages I thought of going with a Generac back up generator until I got a couple of estimates for a whole house unit (one for $10k, and another for $13k).... and one of those guys said the generator runs full RPMs (not variable speeds as needed) so all I would get is about 2 days if my propane tank was full.

I do have gas run in to my garage where my gas water heater is out... so if going with a generator, I'd just as soon get a large portable one (I've seen some pretty big generators on wheels) and have a connection added to the gas line by my water heater (flexible line) so I can roll the generator just outside my garage which is where the power comes in to the house and have an electrician install the necessary connections where I can plug in, fire up, and be in bidness

The reason I was thinking of the portable generator route is because I'm pretty sure I can get one considerably cheaper than the Generac unit and I', hoping to find one that is variable speed where it automatically turns up the RPM as needed when more electricity is being demanded (surely there's a generator that functions this way to save fuel, right?)

Just wanted to get thoughts on whether this all sounds doable and to see if anyone recommended a variable speed generator large enough to run an entire house that is one wheels (I like the idea of keeping it in my garage when not in use anyway)

My house is pretty standard... Central HVAC, couple of refrigerators, one freezer, standard lighting so it's nothing high end in terms of how much juice is needed to run the entire house (I know, at some point I need to figure out how much juice is needed - so I'm speaking in general terms to be able to start looking at generators)

I know folks have been thinking of back up power so I wanted to get some ideas from the resident experts. Thanks!
 
If...you decide to run the house off of a generator, you better get a disconnect switch to remove the service from the grid. Harm can happen to utility workers by back feeding the electric lines.
 
Doesn't there have to be a control box involved to use when activating the generator to power the the house?

Wouldn't this controller provide a disconnect switch to prevent what you are speaking of?

I'm just now learning about all this so let me know and I'll add this to my notes.
 
Krich said:
The reason I was thinking of the portable generator route is because I'm pretty sure I can get one considerably cheaper than the Generac unit and I', hoping to find one that is variable speed where it automatically turns up the RPM as needed when more electricity is being demanded (surely there's a generator that functions this way to save fuel, right?)
Click to expand...

The RPM is required to be constant to get 60hz. No generator runs at variable speed.
The fuel used depends on the loads applied to the generator.
 
The fuel used depends on the loads applied to the generator.
Click to expand...

That's too bad and makes generators to not be very efficient.

If it's running wide open all the time, it's going to be using more fuel than necessary

Seems like somebody would develop a way to do this more efficiently
 
Krich said:
That's too bad and makes generators to not be very efficient.

If it's running wide open all the time, it's going to be using more fuel than necessary

Seems like somebody would develop a way to do this more efficiently
Click to expand...
I believe most of the better ones produce a dirty wave form AC output maybe even 3 phase and then run it thru a full wave rectifier producing DC the DC then is then sent into a sine wave inverter and the output is a constant 120/240V 60Hz.



This would be a much more stable power and the engine governor speed would not need to be perfectly controlled.

I’m not an expert on these and have thought about getting something for years and haven’t because our power is pretty stable where we live. If I did buy one I would get a portable and set up a separate power circuit for just a few critical things. Furnace, freezer, fridge, microwave, TV, and one or two lights. I would get gasoline powered and I have 6 5 gallon cans I would use to keep it running.
 
I have used a cheap 5000 watt Coleman generator for 20+ years. Power outages are infrequent but sometimes may last a couple of days. I power my whole panel but keep the breakers for heavier loads flipped off and add them selectively as needed. Also I don't run it continuously. No worries with electronics as they all have power supplies that convert to DC anyway. I have considered an inverter generator but it wouldn't prove cost effective in my case.
 
Last edited:
Just about everything today has some sort of a computer/processor built into it these days.



My sister lives in a rural area and the power is really dirty and she has a long list and an expensive list with unexplained failures of all kind of household appliances. IMO the grid is not really getting better over the last 10-20 years as the demands keep getting higher. EVs may be the straw that breaks the camels back.



Based on if you feel like I do then some form of backup might be a good insurance plan. We have a large freezer and as her dad has beef cows we have it pretty full with a lot of dollars to go bad. Most of the time here our outages are in the winter and snow related so food can be moved outside. If we don’t open the door stuff stays good for close to a week.



I have also seriously been thinking about an alternate gas fireplace type heat source that requires no electric. We have a gas stove in the kitchen that works fine without power if we use a flame stick to light the burners so that also helps.

A good overall plan is a good idea. Even if you run an extension cord and have a way to unplug and plug in your furnace and T-stat transformer and stay warm. It is no fun riding out a storm in a cold house.
 
Krich said:
If it's running wide open all the time, it's going to be using more fuel than necessary
Click to expand...
You're still not understanding, the generators run at a constant RPMs and the throttle opening is varied to maintain that RPMs according to load. Light load, light throttle opening, light amount of fuel used.
Generator run time/fuel consumption is usually calculated at 50% of full load/full output... Keep your electric loads low and extend run time/save fuel...

Home generators don't maintain 60 cycles per second as accurately as power plants do. They use oscilliscopes/computer controls to keep it dead on. Plug in an inexpensive electric clock with synchronous motor that times by the 60 cycle power and 10 years later it will still be reading the correct time if no power failures over that period.

I've considered a generator but power here is exceptionally reliable for now. Even a few years ago when the entire Eastern half of the USA was scandalously without power for a half day to a day all around us, power here was only off for a few seconds, surprisingly.
 
20+ years in a suburban "hood" with a horrible grid. Houses up and down the street leading into our neighborhood never lose power - someone sneezes hard and we lose power. Just got wacked with the remnants of Ida, F2 tornado missed us by a mile :O/; electric was out for 5 days - do have a portable 5k unit that keep the sump pumps, fridge, water heater and internet up but it's always a mess of wires - and just as bad cleaning up.

Point is, I'll be investing in the whole house, 22k+ NG version. Thinking about doing a how-to video on the whole process, from selection to installation; pad, gas, electric.

Did read somewhere - hopefully not accurately - that the whole house stand by units should not be run for any more than 24-hours at a time, which seems completely contrary to their intended use.

For the most part, they seem to be priced within a $1,000 buck of each other (comparable units).

Believe you need to be an authorized dealer for the Generac units, does anyone know for sure??

Also, these things do need to be serviced at least once a year. Neighbor across the street has (had) a Generac unit that failed this week - 18" of water in their finished basement!!
 
If your panel allows it, there an alternative to using a transfer switch: a generator interlock. The general idea is to add a breaker through which the generator feeds the panel but the interlock physically prevents that breaker and the main breaker from being on at the same time. This is what I did in my house. I know that the generator I got won't power the entire house but, if the power goes out, I can turn on and off whatever I need to be running at a given point in time.

Regardless of the choice you make, make sure to get permits and an inspection. That keeps you protected and prevents insurance from causing problems should there be a problem later on.

If you do decide to use an interlock, find a kit that you/electrician can install but first check with the local inspector if he will accept it and, if not, what will it take. In my case, he required a special part to screw and hold on the new breaker (which proved a bit hard to get given that my panel is old).
 
I have a 6,500 watt generator in my garage, I have several 120 outlets and a lot of extension cords . This will run frig, lighting, TV, microwave, coffee machine and electric frying pan , enough for me for a day or two. total cost about $1200 with accessories . also get a big spare 5 gal tank with stabilizer and lots of extension cords .
 
I have a welder (wink) 240V receptacle near the front my garage that I use to backfeed my panel. But I don't recommend that for everyone. I built and wired my house so I know it presents no stress to the wiring.

I could get by with a 3500W generator but most of them are 120V only and I need 240V for the well pump. I have considered a 3500W inverter generator and an autotransformer to get 240V with a derived neutral but don't know the reliability of the autotransformers.
 
Hamberg said:
Did read somewhere - hopefully not accurately - that the whole house stand by units should not be run for any more than 24-hours at a time, which seems completely contrary to their intended use.
Click to expand...
We have a Generac whole house standby unit. Its works well. Main drawback is it runs on propane so in a long event it has a finite fuel supply. NG is a lot better IMO. Yes the supply could get interrupted but the chances are pretty low. I see a lot of people here say the have a portables and keep extra gas around. 15 or 20 gallons a of fuel really won't last that long. I have a 1000 gallon propane tank and that wouldn't really last that long. I figure if we had an outage that I anticipated being long, I would shut the standby off and just run it as necessary. If something really bad happened, hurricane, snow storm, etc. you will have a hard time getting fuel and most likely nobody is going to be able to deliver fuel either.

I have a friend that bought a Generac a year or two ago and he asked how long it could run. He was told the longest this company had experienced was 3 days continuous. They told him if he needed to run it for days to shut it off every 24 hours and check the oil.
 
IMHO The best, by far, system is either a whole house generator or a portable gen that interfaces into your circuit breaker panel. Extension cords are a hassle, especially in a power failure during a storm. Using extension cords would probably mean that something you want, won’t get power. Interfacing into the panel is not that hard and there are several ways to accomplish it.

I have a Champion 8750 open frame inverter generator that I got off Amazon for less than $1500. Inverters produce "clean" power that is safe for sensitive electronics. The 8750 Champion produces 7K watts continuous power (8750 Watts starting) and will run all our lights (which are LED), the refrigerator, computers and the microwave oven easily. It is not sufficient for the electric water heater, A/C or Heat Pump. My house heater is a heat pump. Someday, when the heat pump needs replacing, I'll probably replace it with a Natural Gas unit but for now, we have two Natural Gas fireplaces that put out 29,000 BTU's each for heat.

Properly hooking a generator to your circuit breaker panel involves installing an appropriate sized dual pole circuit breaker (for 240volts). A 50amp 2-pole circuit breaker is good for 12,000 watts. A 30A 2-pole circuit breaker is good for 6k watts

If you are hooking a portable generator to your panel, a male plug will be installed outside your house from the circuit breaker that was installed on your panel that a generator cord can be plugged into. My Champion Generator has a 240 volt-30A 4 prong outlet. A 50ft. - 30Amp cord to go from the gen to the input plug on the house is about $110 on Amazon.

https://www.amazon.com/dp/B0881D4YB...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

A Transfer switch or a mechanical interlock (as mentioned in post #13) should be used to make it legal. A transfer switch can be manual or can be automatic depending on how much you want to pay. A more economical alternative to the transfer switch is a mechanical interlock installed on your panel which forces you to shut off the main breaker prior to closing (turning on) the generator breaker. These interlock devices can be found on Amazon as well. The idea behind the transfer switch or interlock is two fold: first and foremost is to isolate your panel from the power grid so as to not energize the grid with your generator. Energizing the grid could be hazardous to the power Company workers. Second, the system allows you to select which circuits to be energized by your generator.


An initial step in setting up your system is to map your panel and determine what each of the breakers energize. This takes a little time but is important because trying to figure this out during an emergency can be hard and potentially dangerous. Do it in good, daylight conditions. I made a spreadsheet listing my breakers and what they control as well as putting an asterisk next to the breakers to be closed (turned on) while on generator power since I can’t run everything with my 7K gen.

All this is really not rocket science if you are not afraid of working with electricity and use common sense. Post #15 talks about “Back feeding” your panel using an existing circuit originally designed for a different piece of 240 volt equipment such as a welder, a dryer, etc. While theoretically, there is nothing wrong with this, it is frowned upon since you would convert your female plug from your generator to a male plug to insert into the welder outlet (or dryer, etc). The male plug would be hot and could cause an unknowing person to get shocked if they were to unplug the male adapted plug and touch it. I don’t know who would do this, but it could happen. I guess a person could put a warning tag on it instructing people that a generator is in use and the plug is hot. On the other hand, I could see how a professional installed input plug could be energized as well and be hazardous.

If a power failure occurs, I wait a little while to try to determine if it is a long term failure or short term. If you have a high dollar automatic system, it would kick on the gen and go to aux power right away. When I determine it’s time to start my gen, I will turn off the main breaker in the panel and then fire up the generator. Next, verify that the gen is plugged into the circuit going to the panel and then go to the panel (with a flashlight since the panel is in a dark spot). I then turn off all my breakers, close (turn on) the generator breaker, and (one at a time) turn on the breakers that have an asterisk next to them.

The Champion has a 4.2 gal tank and will run for 10 hours on a tank. I have tested this using average power use during a power failure. With 10 gal of extra fuel (that I usually have), I can go for over 30 hours before either having to buy fuel or start syphoning a car. I bought a Natural Gas conversion that I may install if I get some extra time but then I'd have to get fittings to hook it to a NG pipe line at the house.
 
68bucks said:
We have a Generac whole house standby unit. Its works well. Main drawback is it runs on propane...

I have a friend that bought a Generac a year or two ago and he asked how long it could run. He was told the longest this company had experienced was 3 days continuous. They told him if he needed to run it for days to shut it off every 24 hours and check the oil.
Click to expand...

We are NG and have never lost that, so I think we will be good there. Again, logically seems counterintuitive that it would not be able to go for much longer!? This last week ours was out for 5-days and the little guy we had (3500W B&S engine) ran continuously the whole time.
 
One other point that the OP made was a system for long term, like end of world stuff. I don't think any of these system will provide power for weeks on end. I think we are talking about systems for multiple days to a week or so. If you want an end of world system I think you are sort of stuck with something that provides renewable power, solar, wind, batteries, all that sort of stuff. Whole different thing. Am I wrong?
 
You must log in or register to reply here.

Latest posts

Back
Top