Energy density: 9,7kwh/l
Diesel engine efficiency: 30%
And the winner is…. The wind generator! Given that we normally have a couple of days with winds around 8-10ms I should be able to get some energy into my batteries. Since I run a 48 volt system I need a 48 volt wind generator. Fortunately Southwest Windpower makes a small, 120cm diameter, generator with an integrated controller. The controller makes sure that the batteries receive the correct voltage while charging.
Have a nice vacation, I know I will.