I figured someone would chime in with something like that, as dual 200's seems to be the standard around here, anymore. I don't think a new house has been built in my neighborhood since 1995, with anything other than dual-200's.
I did once look at buying a house that had a single 400A main, which I thought was ideal. I'm not sure why that's not more popular, but at least around here, 2x200A seems to be the much more common approach for larger homes.
400A main service panels are substantially more expensive than 2x200A, which may be why you don't see them as much, and it may get many folks into 3 phase which is also not common, and often an expensive addition.
Correction to earlier statement: it was 12F, the last time our power went out, because it's 12F outside right now.
This little outage was too quick for a generator to kick in, though. I think it lasted all of 10 seconds.
Someone mentioned storage awhile back, and as much as I hate complicating this house even further, I think it's something I should consider. It would remove most concerns about huge shock loads, as our oldest AC compressor pulls 60 amps for a brief second during startup, as does some of my shop equipment. It would also might allow me to retire a small army of individual UPS systems, assuming I was able to offer similar protection at the whole-house level, although there's more involved with that.
I'm an EE, so no concerns with all of those details. But as mentioned previously, I hate leaving behind complexities that someone else may need to deal with, in the future.
One thing to reemphasize is that depending on loads, and what state the battery storage system inverter is in, there may be a gap of a couple of seconds during switchover. Some of that delay has to do with how the grid gives up, and how fast it goes out of voltage specification. E.g. a slow droop into brown out may take longer than a sharp cutoff. So, speaking from experience, for critical loads, like life supporting medical equipment, or internet / local servers, you probably still should use / will need UPS units. This has no bearing on your site, but here, about 80+% of the outages happen with no more than a flicker, and the peripheral electronics stay on. For the other outages, the peripheral electronics reboot. How well your devices tolerate the hiccups is going to be very dependent on site specific issues (how your power drops, your wiring, other loads, and the particular equipment).
I think that you can manage the viscosity and flow of heating oil going underground to a diesel. For starters, insulate the pipe, and then also insulate the trench 6-12" each way from the piping, and at least four inches thick. That's pretty routine farther north. Most diesel gensets have options for fuel preheat, as well as engine preheat, so that is probably a worthwhile add for both for your site, if you decide on diesel.
I'm sure that you can take care of the routine service items on a generator. I think an issue to consider is getting warranty support, or a blown part after a storm..., and whether getting routine service might be worth the price of a good relationship with a great service group. As I am sure
@grsthegreat can attest, in my experience, good mobile generator service folks tend to drive around with $$$ worth of spare parts on board.
I do take care of my own genset, but that's because it isn't new, and parts are not always easy to source. Plus, I have an oddball generator model because it is both small and supports both 120/240 and 3 phase, something that I couldn't readily obtain new.
As a counter example, I do pay extra for service on my well, because those folks are the only competent folks for well repair in the northern half of California and Nevada, and they have been really great about turning up quickly when we've had an issue. I view the extra cost as a small price to pay for having timely backup for water.
That sort of professional backup might, or might not be worth it to others for generator backup, especially depending on who is doing the work. E.g. My neighbor with a Generac backup system (into 2x200A) no longer uses any local service technicians from the area, and instead uses a crew from 140 miles away. The local folks, plural, couldn't get her generator up and running for six months. For the commercial generator equipment at work, we used the same crew. My personal observation is that generator service requires all the skills of a great mechanic, plus skills pertaining to electrical power generation and regulation, something that not many electricians have a good grasp on in my experience. It is not a job that everybody does well.
As an aside, for those of us that have diesel tractors, I think it is a bit easier to have a diesel generator as we already stock diesel, and keep it fresh and ready to go. Don't get me wrong, I think propane is a great fuel for a backup generator because it does keep indefinitely with no attention, but one needs to have enough on hand for when things go down the tubes, as that often lasts longer than most folks estimate.
All the best,
Peter
