When You are Ready for that Generator IV

Part 4 of 6

Fourth of a series of articles that will run through the ins and outs of buying a generator

Kilovar’s personal home standby, 17kW Cummins

Last Time

Last time we covered PTO Generators, if you missed it here is a link

When You are Ready for that Generator III

Permanent Home Standby Generators

Once you move into this size you are looking at a sizable investment, both for the equipment and the installation. For equipment plus installation plan to spend 10 grand plus, and I would be very skeptical of an installation as low as ten grand. You are no longer looking at equipment, you can move around and store where you want to. These generators require a permanent pad to sit on, are hard wired into your home or business. They require a dedicated fuel supply that has sufficient capacity for several days at minimum (your fuel choices are limited to propane, natural gas, or diesel). They are almost always fully automatic; they will start and supply power when the utility fails and shut down when the utility returns. They are typically considered part of the home and stay with it when it is sold.

So, what considerations should you make before you sign a contract? There are a few things you need to look into before you sign the contract and make the deal.

1. Which one should you buy? I have been careful to avoid saying, buy that brand and not that brand. It’s up to you! One of the brands spends more on advertising than the rest combined by a factor of five or more. Does that make them the best? I will let you decide that, but it does mean they have the best marketing department. Do yourself a favor and do some research. Check customer satisfaction ratings, where is the closest service dealer, do you like the options, do you like the appearance, etc., and any other items important to you. The primary companies in the home standby/small office business are Cummins Home Power, Kohler Home Energy, Generac Power Systems, Briggs and Stratton Home Generators, and Champion Power Equipment/Home Standby Generators (Cummins pictures are because I own a Cummins, not because I am trying to sell you a Cummins). Winco offers some standby generators in the correct size range but classifies them as commercial. Virtually all of the listed manufacturers, except Champion, do offer diesel models if you want them. Also except Champion, they will offer air cooled or water cooled depending on size. Air cooled units run at 3600 rpm. Water cooled units mostly run at 1800 rpm, but at least one manufacturer offers 3600 rpm models. Water cooled units typically cost two to three times more than a air cooled of the same size. If you want to price shop, here are some links to online outlets. I do not recommend you buy a permanent home standby online, it would be a mistake, see the next section. However if you see a portable or a PTO you want, get your wallet. https://www.norwall.com/, https://www.electricgeneratorsdirect.com/, https://apelectric.com/brands/

   

   Kilovar’s optional in home display. This provides all the same controls and displays as the generator display without going outside.

2. This may be the single most import piece of advice in this section. Your dealer is more important than the brand you buy. Not only will they sell it, but they will maintain it, and repair it if it breaks. This should be a relationship you plan to keep for as long as you own the unit. So face to face consults are very important. If they give you the willies, move on.

3. Can I just call up the generator company and they will put one in for me? You can, but it’s a bad idea. You generally want to have them come out and go over what you want, see if they agree with your size calculations, or provide a size recommendation with an explanation. (e.g., we always put 27kWs on these houses is not a load calculation and not an explanation of how they sized your unit). It never hurts to talk with more than one company. Once you agree, the dealer should provide you with a written quote, with itemized costs and a list of equipment supplied with pricing. Pay attention to a quote vs an estimate. A quote is a firm price, an estimate is a guess, don’t get burned by an estimate. You can add language for change orders to quotes if they wiggle. Most contracts are 50% down, the remainder on completion. Do not ever sign a 100% down contract, ever.

4. How much are you backing up? Since a permanent standby generator is automatic, you have to decide in advance if you are backing up the whole home/office, or just some select equipment. The latter requires the select loads to be moved to a separate sub-panel, we will cover more on that later. There is another option, pretty much all home/small office standby generators have some form of load control available as an accessory. They control four or six loads based on a priority setting you select, you do not have to use them all. If the load goes too high on the generator, it shuts power to the lowest priority load, and will continue to remove loads based on priority if generator load continues to increase. The control will restore the loads when generator load goes down. Using this feature can let you power your whole home without the concern of overloading your generator. It can also let you downsize if you are willing to put up with the inconvenience. Your dealer can also get aftermarket load controls from https://www.pspproducts.com/ if he doesn’t offer a good solution.

   

   Kilovar’s load control panel. This de-energizes the 60 amp EV charger outlet in the garage if load goes too high. Presently the EV outlet is unused but preparations are in place.

5. Where do you want the generator to sit? Ideally the generator should be located close to the main electric panel, or the gas meter if natural gas is your fuel. In California that’s easy since both meters are generally in the same location, but here in Ohio they tend to be on opposite sides of the house. Remember generators make noise, even quiet ones. Putting it outside the master bedroom does not a happy couple make. Always pay attention to openings where CO might enter the home and avoid those locations if possible. NFPA 37 recommends 5 feet minimum between the generator and any flammable surface on the structure or opening into the structure. Once you pick your spot, then stick to your guns unless there is a compelling reason for a change. The generator installer will be looking for what is good for him, not you

   

   Kilovar’s location, that window in the laundry

6. Your house/office was already plumbed for natural gas or propane, can you just tap my existing plumbing? Generators use a lot more fuel than household appliances, so chances are slim. Fuel pipes that are too small on gaseous fuels can cause the gas pressure to drop at the generator when it runs under heavier load. Low gas pressure can cause the engine to run lean, which can damage the engine. This is an important item to go over before you sign your contract. Make sure you ask in writing and you get a response in writing that either fuel supply is adequate, or what work needs to be done to correct it with the cost. Optionally you can request a load bank test to show it has enough fuel to run full load, however many small dealers do not own a load bank. Make sure you save all those documents in case you run into a problem later. I have some alternative suggestions to small piping in the final post.

   

   Typical small load bank

7. Your installer says the generator doesn’t need a pad, is that true? NO! Generators always need a pad, but there are pre-made pads the installer can drop in place after they have levelled a spot and put down some base and compacted it. If the installer prefers to pour a concrete pad, that works too. The generator should always be bolted to the pad. Important note the gas line connection should be made including the flex line supplied with the generator. The flex line should be straight horizontally and not used in lieu of an elbow. Electrical conduit connections should be done with flex or with vertical slip joints. (note on the picture on the top, my installer did not put in slip joints, I will probably have to fix that) Generator pads always settle, allowances have to be made for that movement. You may be getting my drift that some contractors try to get away with things, I have a responsible dealer friend who calls those guys “chuck in a truck.”

   

   Gen-Pad is one of several aftermarket pad manufacturers

8. Once it’s installed, can you hide the generator behind some vegetation or a wall? Generally, no unless you have left a wide graveled working area with a pathway in. Generators need regular maintenance, and technicians need access to the side panels to access the internal parts. Like any engine, the oil should be changed annually or when sufficient hours occur during an extended outage, and cranking batteries usually last about three years. Additionally, generators need a large supply of fresh cooling air, anything that restricts flow or causes air to recirculate can overheat the engine. Recirculation is especially a problem inside accent walls where hot air (and CO) can get trapped.

That’s it on getting your generator! I know there is a lot to digest but take your time and get it right.

Next Up

We will talk about getting that power into your home of office. Regardless if you have a portable, a PTO, or a permanent home standby, the electricity has to get from the generator into the building. Running extension cords in doors and windows just isn’t going to cut it. The battery backup gang will need this one too.

Not Convinced Yet

Then take a look at these latest post by the Energy Bad Boys and The Electric Grandma

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