A different approach for GT w/ BB?

Re: A different approach for GT w/ BB?

Thanks for the feedback guys.

We use 50kwh per day because we're a family with kids in a big house with a nice big lawn and a vegetable garden. My home office has computers, printers, UPS's, fax machines, router, satellite modem, and cordless phones.

Thanks for the Xantrex links. I should have been more clear. I started thinking about alternatives after reading the Xantrex, Outback, and SMA literature.

I do not want to run my electric stove or water heater or clothes dryer from my backup power. During grid outages, the plan is for those breakers to stay off.

However, I do want to have access to any other circuit in the main panel, and the flexibility to choose which I want to use during grid outages.

This is a 3-level house with a separate large multi-purpose shop building. The main panel has a lot of small breakers in it. A lot. I'm not interested in eliminating any of them from available use during outages.

When I'm on backup power, the plan is for every light in the house to be off except a few LED or CFL fixtures. I'd like to be able to run one computer for short periods with internet access, no UPS. My refrigerator and freezer will be on. My water well will operate in standard "on demand" mode with the pressure tank. We can massively reduce water consumption, cook outdoors in warm months, cook indoors on wood-buring stoves in cold months, and just generally cut back.

In this type of situation, the house sort of "becomes a 30amp service" rather than a 100amp service, if that makes sense. My inverter should probably be able to handle a 5kw peak for occasional simultaneous fridge/water well events. Other than that, electric consumption can be quite low.

The general idea is to replace the restrictive nature of a dedicated circuit subpanel with a less restrictive, manually operated system that places no limits on where or how I choose to use my backup power.

Code will require the transfer switch to meet or exceed the panel capacity, so I'll need a 100amp or bigger manual transfer switch. First google result was a Ronk 7103 Manual DPDT 100amp xfer switch list price $400. Mebbe I can reduce that cost by shopping around a bit.

If we have an outage for more than 12 hours while we're out of town, my neighbor can throw the switch for me. In this little neighborhood, we already have arrangements with neighbors for house-watching and freeze-protection during winter power outages while someone is out of town.

Anyway, I don't mean to clog the board with justifications.

I'm a noob. I'm interested in an alternative approach to a GT-BB system.

I really think of it as an off-grid sytem that allows the user to grid-tie and net-meter if he chooses to do so. I know it's "different", but it's also very straightforward. For $10,000, why not try to get exactly what I want? :cool:

I know there are some EE's and a lot of expertise on this board. I'm interested in feedback pertaining to code-compliant design, experience with similar ideas or systems, suggestions for hardware, reasons why some element will or will not work, and particularly, whether a single inverter can serve the typical GT functions of synchronization and auto-isolation (when grid power goes down), and also user-elected BB when the grid is off. Maybe there's a trick or a workaround? Maybe I'll need 2 inverters?

Thanks!