What's a good mid-priced decent-quality solar inverter/charger for this application, such as a Growatt or MPP? What size? What's the minimum amount of battery and array size that I need? I want to run on solar as long as sun is shining, grid as a backup when not. If grid is down and sun is up, it powers it. Roof-mounting the panels is not required.
I have a 34' class A motorhome with two 13,500 BTU roof ACs. Would like to convert to a single mini-split, probably 18k BTU dual zone such as this Bosch. The brochure (page 21, BMS500-AAM018-1CSXRA / 8733942703) claims 1,547 watts, requires a 220V single phase 60Hz, min circuit ampacity 18A, breaker 25A. Big air conditioner, but we're in Florida full-time with four people inside, kitchen, thin insulation, etc.
My best guess as to what I need:
I have a 34' class A motorhome with two 13,500 BTU roof ACs. Would like to convert to a single mini-split, probably 18k BTU dual zone such as this Bosch. The brochure (page 21, BMS500-AAM018-1CSXRA / 8733942703) claims 1,547 watts, requires a 220V single phase 60Hz, min circuit ampacity 18A, breaker 25A. Big air conditioner, but we're in Florida full-time with four people inside, kitchen, thin insulation, etc.
My best guess as to what I need:
- Growatt 48V 6kW Split Phase 120V/240V Package 2 x 4500W MPPT (2 x SPF 3000TL) (Seems overkill but best I can find with 240V.)
- 12kWh of cheapy lead deep cycles just for a buffer (Would set the grid fallback voltage to something high like 5% DOD to maximize battery life.)
- 2000W of panels
- Run RV air conditioner on solar while the sun shines
- Switch to grid when it does not
- NOT grid-tie. Allow for boondocking with partial air conditioner usage during the hottest part of the day--so no grid tie.
- Running boondocking after solar hours is not required, to keep down the battery investment
- Roof-mounting panels or batteries not required
- Switch the inverter from the air conditioner to power other loads if needed--so a dedicated solar mini-split such as this isn't an option. Grid-down option to power other equipment.
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