Buying a portable generator

[Jerome Stanek]

I see Woot has a Raven MPV7100 Hybrid Riding lawnmower Power generator and Utility Vehicle this morning

[Ole Anderson]

Any gas engine that you only run once or twice a year is going to be problematic. People don't take care of them and then when you really need it, it doesn't start because the fuel system is all gummed up. I live in a house where the previous owner abandoned two generators in the basement. I don't know if either of them runs.

Very simple: When you are done, close the fuel shutoff valve and run the carb dry until the engine quits. Put Stabil in the tank first. No gas in the carb to gum up. No need for extra carbs. Same with seasonal equipment, get it warmed up so it will start on one pull, dump the gas out, start and run dry.

As for whole house generators, I think most of us would like one, it is a matter of $500 vs $5,000 or more, the difference will buy a shop load of nice WW equipment and supplies that will get used a lot more frequently than a whole house generator. If you live where power outages are a frequent thing, or you have a boatload of money the equation changes.

As for generators in the basement, in a word: Don't. An entire family of five near us died last year from carbon monoxide poisoning, I am guessing from a faulty exhaust system on the generator they were running overnight in their basement. I have designed buildings with big (as big as 250 kw) gensets inside, but those have huge frequent air exchanges from the radiator fans positioned in outside walls along with engineered exhaust systems.

[Al Launier]

This may be lengthy, but I wanted to provide you with my recommendation when selecting a portable generator for power outages.

There is a tendency to under power portable generators for home emergency use when confronted with the cost of these systems. There are some things to consider when purchasing & using a portable generator to provide electrical power for your home and would include the following:

1. Identify in advance which circuits to power during an outage.
2. Sufficient power capacity to service necessary circuits for household use, especially if multiple circuits should be required at the same time, i.e. furnace, well pump, microwave, etc. So allow for this power surge.
3. Circuits to consider could include :
   
   1. Furnace/boiler for heating the home
   2. Well pump for water supply
   3. Freezer & refrigerator to store food
   4. Microwave for cooking
   5. Bathroom & bedroom lights
   
   
4. In my opinion a portable generator for emergency home use should have a minimum power capacity of 5,000 Watts with allowance for surge. Most portable generators are rated with a 25% allowance for surge, i.e. a 5KW system would be rated at 6.25KW.
5. I had a 5KW system for several years & then upgraded to a 7KW system. This was a significant improvement.
6. A portable generator should include receptacles for 240VAC, as well as 120 VAC. 5000KW +25% surge
7. A licensed electrician, or qualified person, capable of electrical installation in compliance to local code to prevent overload to circuits to a house service panel. This includes proper grounding, whether using the ground from the house service panel, or using a copper rod driven into the ground.
8. If done by other than a licensed electrician, at least have the installation checked by one.
9. Voltage regulation for electronic devices such as controllers on boilers/furnaces, computers, etc. to avoid damage.
10. Transfer switch to prevention electrical shock to public service linemen repairing.
11. If manually turning on circuits powered by a generator, switch off these circuits before turning on the generator, to allow switching on these circuits one at a time to prevent a sudden overload of the generator.
12. The engine on a generator system is much more likely to fail than the alternator. A well know engine such as Honda, B&S, and Tecumseh will ensure reliability.
13. Train your wife, or mature children, in the event you are not available during an outage, how to set up & start the generator with emphasis on switching off the circuits before starting the generator & labeling the circuits to switch on afterward. Recently we had a situation where my wife would not have been able to setup our portable generator when I was hospitalized while a blizzard condition was forecast the next day. Fortunately I was scheduled to be released next day when the storm was forecast. I checked myself out of the hospital a day early to get the generator set up.
14. Have plenty of fuel on hand to weather anticipated outages for your area.

[Roger Feeley]

Ole, I absolutely agree with you that preventing carburator problems is fairly simple but many people forget or just don't bother. I think the two non-functional generators in our basement from the previous owner is a good example. Probably, anyone in this forum is savvy enough to take care of the engines.

We live in the DC area where major outages happen fairly often (more than never). It's not that unusual to be out of power for several days here. There are loads of houses with generators.

We used to live in suburban Kansas City and no one had generators. In our case, there were two hospitals nearby and all the lines were buried. So if a substation took a hit, we and the zillions of customers also hit were a very high priority. I think in the 20 years we lived in that house, we lacked service for maybe an hour.

[Wade Lippman]

1. In my opinion a portable generator for emergency home use should have a minimum power capacity of 5,000 Watts with allowance for surge. Most portable generators are rated with a 25% allowance for surge, i.e. a 5KW system would be rated at 6.25KW.

That's quite an opinion. I got through two week long outages with a 1.6kw genny quite well thank you. Sure am glad I didn't have to find 3 times as much gasoline.
(of course I didn't have to power any pumps, but your "opinion" says nothing about pumps)

[Al Launier]

That's quite an opinion. I got through two week long outages with a 1.6kw genny quite well thank you. Sure am glad I didn't have to find 3 times as much gasoline.
(of course I didn't have to power any pumps, but your "opinion" says nothing about pumps)

But what did you power with it with only 1.6KW?
My opinion was based on the (5) circuits, which included the well pump, and the comments noted in my post immediately preceeding them.

[Charlie Velasquez]

Should you choose to go with a portable instead of a whole house set-up, an interlock will give you access to all your circuits. With judicious use of the circuit breakers, and the understanding that it is an emergency situation most could easily get by with a 5,000w unit and probably a little smaller.


Using Al's list I would add some modifications. (when I copied and pasted to my word processor all the numbering disappeared so I had to add them.)

1. Identify in advance which circuits to power during an outage.
Interlock lets you use all circuits

2.Sufficient power capacity to service necessary circuits for household use, especially if multiple circuits should be required at the same time, i.e. furnace, well pump, microwave, etc. So allow for this power surge.
It is seldom that you will need all these circuits at the same time. Know what your demands are and when and plan accordingly. A good frig only runs a few minutes an hour. Set it as low as it goes. Run it for 20 minutes to get to about 33, then switch it off and let it float for a few hours till it gets to about 40.Same with well pump, water heaters, microwave (would need to rethink this) sump pump

3. Circuits to consider could include : Certainly good candidates with a couple of suggestions
A. Furnace/boiler for heating the home
B. Well pump for water supply No need to run it continuously
C. Freezer & refrigerator to store food See above
D. Microwave for cooking
A microwave uses its rated cooking watts plus some to run the innerds. It is not unusual when I measure appliances in our schools for a 600w microwave to use 800w-900w. They are very efficient with that 800-900watts but you may not be interested in efficiency. You may be willing to use more watt-hours to keep the actual watt draw low. A crockpot will take more electricity to cook a meal but it will max out at about 250-300watts. Those beverage warmers for your morning coffee come in about 150-250 watts, also.

E. Bathroom & bedroom lights
I would add LED night lights to the hallways. At less than 1/4watt you provide safe pathways throughout the house. Have specific lights be designated for emergency and make sure they are LED. Lamps are the easiest to outfit. But again, if it is not visually intensive, night lights are adequate..

Additionally, a small 5,000Btu window A/C could be powered by a smaller generator.
TV and stuff can be watched via a computer monitor and internet access

[Al Launier]

Good mods Charlie. If I still used a portable generator I would keep your suggestions in mind.

However, I must say that now having a whole house standby generator is such a relief knowing that we would be powered up should we have another power outage, especially if I should be away from home, or if this should happen while having guests at home.

[Ole Anderson]

Interlock lets you use all circuits

Googled generator interlock and came up with this: http://natramelec.com/?gclid=CIjDw-LbhM4CFRIoaQodkEcNSQ I emailed them to see if they have one that fits mine (an Arrow-Hart)(sure glad my buddy talked me into a 200 amp panel 41 years ago!)

And frankly, unless you keep your house lit up like an airport runway, use all the lights you need, they don't draw that much, especially if you have started to convert most of your incandescent bulbs to LED or CFL bulbs. Motor and heat generating devices draw most of the juice, not electronics and lights.

[Robert Payne]

Googled generator interlock and came up with this: http://natramelec.com/?gclid=CIjDw-LbhM4CFRIoaQodkEcNSQ I emailed them to see if they have one that fits mine (an Arrow-Hart)(sure glad my buddy talked me into a 200 amp panel 41 years ago!)

And frankly, unless you keep your house lit up like an airport runway, use all the lights you need, they don't draw that much, especially if you have started to convert most of your incandescent bulbs to LED or CFL bulbs. Motor and heat generating devices draw most of the juice, not electronics and lights.

Ole,

Charlie Vealsquez is technically correct that an Interlock does allow all of the circuits to be used, but one can indeed overload the generator with many of those circuits. You showed a picture of your panel (I assume), but although you show a generator circuit breaker just below the main breaker, it does not appear that there is a valid interlock installed. Here is a picture of the "Kit" that will be supplied for my panel, a 200 AMP Murray/Siemens panel. This simple device is added to the cover of the panel and it will allow only the Main Breaker or the Generator breaker to be in the ON position concurrently. When the home has a power failure, the Main Breaker is moved to off, high amperage circuits are turned off, the generator is turned on and the generator breaker turned on. All of the remaining circuits in the panel become activated and no power can flow out onto the grid. Lots less expensive than a transfer switch like those from Reliant that require significant rewiring. Here is a picture of the Interlock Kit available from Interlockkit.com.

[Ole Anderson]

I didn't realize until today that interlock kits were a retrofit and available. I plan on installing one. Ones from National Ram Electronics (natramelec.com) are $70, half the price of those from interlockkit.com. I thought $69 was a lot for a couple of stickers, screws and a stamped piece of sheet metal, but $150, that is crazy, you can buy whole panels for less than that.

I have my high amperage breakers marked with a red marker, they get turned off when running the genny.

[Robert Payne]

Ole,

The problem you face is that it is a code violation not to have an interlock, even if your are personally conscientious during a power outage. The code requires the main breaker to be turned off before any alternate source of power can be connected to a panel buss. The is why transfer switches and interlocks are required -- someone else in your location might not realize the protocol you follow to insure that generator power never flows out to the power grid (you could be away from home). Your homeowners insurance may be invalid in the event of a fire or accident as well. I too will look at the natramele.com site to see if a less expensive version is available for my style panel. As for cost, I suspect the $150 price is more based on low volume than true component costs; a replacement panel would easily cost less than that, but IMHO repopulating it with breakers and wiring would easily exceed that cost.

[Theron Mehr]

You mention your friend has these models and that's why you're looking at them. That makes sense, but you really should first think through what your load will be and what you intend to run if/when the power goes out as a first step. Here's a easy to use check list that's helped others figure out the generator size they actually need. Good luck!

[Joe Cushing]

Hi Dave,

I noticed that the generators you are looking at are a champions. I've done extensive research on the quieter, inverter generators. These are not quite the same as the ones you have picked out but I can say something about the brand itself. Champion is a model that really stood out from the competition. They were hot sellers, so there were a lot of reviews to read through. Most of them were glowing. I asked a question about one of them and the respondent, took the time to tell me how much they love their champion generator, even though that was not what I was asking about. Funny thing is, I don't even remember what it was I was asking. Many others seemed just as reliable. Maybe people were just ecstatic that the lower cost Champion worked as advertised. I wrote this long post about many inverter generators ("http://rationalpreparedness.com/what-is-the-best-small-generator-for-you/"]). If you scroll all the way to the bottom, you can see I picked a champion as my favorite, though all of the brands in the post are worth a look for different people of different needs. Just to reiterate, these generators are a different kind than you are looking at. I was only commenting on the brand. That said, it might not be bad to pick up a little guy, just to run the fridge and electronic stuff, without all the noise, and save fuel, then fire up the big guy, when you need extra power. Maybe that's more money than it's worth. I guess it depends on how often or how long you lose power. I was at the beach today, and someone had one of these little generators. It was a Honda. The crowd of about 20 people using it was literally louder than the generator. It was the first time I heard one of them being run in person. I was happy to see it. It's funny, you hear people complain about noise but I don't know how much quieter they could make it.

[Bruce Wrenn]

As for noise, the little Honda's are in a class of their own. I own a Coleman Powermate2250 watt that's not too loud, but my Coleman Powermate 3250 makes half as much noise. My 5500 watt Devillbiss, with 10 HP Briggs is LOUD! When the power goes out, first out comes the 5.0 HP, then 3250, and if it's an extended outage, the we fire up the 5500. Currently working on installing 5500 watt in a house with removable sides and concrete pad, so I don't have to drag it out. Also adding electric start, as each year the pull rope is tougher to pull.