I know nothing about whole house generators, but would be interested in knowing what you've learned about them.
Sorry for offtopic, but you asked for it
Most home generator models under 20kWA are running on Natural Gas. They could also run on LP gas and generate more power, but no one wants to deal with refilling bottles/tanks if it could be avoided. Going with the Natural Gas option, you'd likely need to upgrade your gas meter to a bigger one, but the charge (if any) should be nominal.
I went with a fully integrated setup, which included automatic shedding (turning off) AC power-hungry devices - Air Conditioners in my case. Unluckily my gas and electric meters were on opposite sides of my house, so I chose to install genny on the gas meter side as electric cable (AWG #1 btw) is cheaper and easier to run as my basement is still unfinished. Part of installing your existing main power panel becomes secondary, where now utility power goes to the new panel, which in my case was installed outside.
There is basically a mandatory annual service (get it or lose warranty) on genny regardless of its use/run hours. In my neck of the woods, it's a ballpark of $400/year. Anyone offering bi-annual service is a thief. What else could I say? My model has "smarts" in the sense that it connects to home internet, and using Kohler's cloud service, you could get alerts, monitor usage, and schedule genny exercise. Not much else. My home assistant could integrate with it, but I haven't thought of good ideas to use it yet. A few years ago, my 20kWA Kohler genny was around 5-6k MSRP, and the total installation was about $11k. Real estate sites say home genny usually sees near 100% return on sale time.
From what I learned, Cummins
HOME gennies are subpar in quality. They may be better in commercial space, but at that point, the brand to go with is CAT. The leading players are widely promoted, Generac and much less known Kohler. Both are good in quality, but Kohler is a bit better.
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