Our 30ft Winnie, towing the MG4 on a trailer, comes in at 12.5 tonne. The V10 6.8ltr 20 valve Ford engine goes great, but it is a tad thirsty, 2km/ltr thirsty.
200ltr petrol is good for between 400kms and 500kms, depends on hills, wind direction and the weight of my right foot ..... there is a certain amount of enjoyment pulling up past a B double in the short overtaking lanes they have around here. The price for that much fun was $400 for 200ltrs of petrol (the cheap stuff) that went up to $600, starts to hurt when the trip is 1600kms each way as the crow flies, so it wouldn't take all that long to recover the cost of 700kWh of battery storage.
Already have the hybrid set up, a Lexus GS 450h, a petrol V6 that develops around 300hp and the L112 2sp 2 motor transmission can develop over 270hp and incredible torque using the inverter board developed by Damien Maguire .... all fed into the near unbreakable Ford 4 sp heavy vehicle auto, I'm hoping this will be the motorhome till the end of my days travelling. ....
Solar is good and cheap over this side, so fuel sort of comes down from the sky ....
T1 Terry