
One of the issues I have wrestled with is justifying purchasing a motorhome that I may use a maximum of 30 days a year and spending a lot of money to upgrade it. What good is it to have a motorhome and investment sitting next to house, uselessly, for 330 days.
How about using the solar energy collected during those 330 days, storing it in the onboard battery banks and powering the house. Solar energy without putting any collectors on the house’s roof.
Well, the 2 battery banks have Victron MultiPlex II that each can generate 30amps @ 120vac single phase. There is the solar panel array and the possibility of (2) paired Firman 3042DF generators. We live in a mandatory evacuation zone in the Tamp Bay area of Florida. We already have (2) paired Westinghouse i4500DF generator connected to (3) 110 gal lpg tanks.
Unfortunately, all these generators only provide 120vac single phase power, not the (2) phase 120/240 vac residential power we get from the grid.
Therefore, I am installing a Victron 100amp Autotransformer that converts 120v ac single phase into 120/240v (2) phase residential power similar to what we get from the grid.
The photo is of a 50amp shore power outlet normally located on a dock but will be mounted on the motorhome to transfer power to my house.
Thanks to highly efficient equipment and maximum energy conservation, my average 24hr electrical usage in July is 41.34kwh or 1.72 kWh per hour. During the warmish November, the average daily usage is 25.07kwh or 1.045 kWh per hour.
That means a very low current draw and the 200 amp, 120/240v service seems grossly excessive.
The 12v battery bank capacity is 13.2kwh and the 48v battery bank is also 13.2kwh for a total useable storage of 26.4kwh.
The battery bank certainly has enough capacity to handle the house without any addition solar power collection for 24 hours in November without any from the grid. Addling the amount of solar collection and/or some generator power for peaks, using the this GMC Motorhome design is close to getting my house of the grid, even though it is in a nearly completely off the grid.
Unfortunately, I only spent $1,511 in the last 12 months on electrical power from the grid. I can’t save enough money to justify solar panels on the roof. It is only my passion for being nearly carbon footprint free to convince me to do it.
My house is a 3 br, 2 1/2 bath, 1,732sf elevated house on a canal with a 1,350sf unheated and uncooled garage, storage and shop below. I am also charging a Chevy Volt plug in hybrid and a Ford CMax plug in hybrid and (2) sailboats with electric propulsion. We only spent $550 on gasoline last year, but we will spend more when this GMC Motorhome is put into service.