The van has three electrical circuits: 240v AC for use when electric hook up (EHU) is available; a 12v DC circuit powered by the engine battery; and a 12v DC for when we’re ‘off-grid’ and EHU isn’t available, powered by a dedicated leisure battery.
The EHU supply will vary from place to place, and can be anywhere between 3 and 16 amps. On a campsite the supply will typically be unmetred, but when available on an aire the supply will be timed (eg €2 for 8 hours) or metred (€1 per kilowatt hour or kWh). We have a 20m cable to hook the van up, with two types of socket in use in mainland Europe.
Inside the van there are five 240v three pin sockets which can be used to power things like a kettle and hairdryer, and recharge all of our various gadgets. When on EHU we will flip the hot water, heating and fridge from gas to electric.
The 12v engine battery circuit is like the one in a car, where you can charge your phone whilst driving.
The other 12v DC circuit is powered by a 90 amp hour (Ah) leisure battery. This gets charged up in three ways: by the engine when driving; by the 240v circuit when on EHU; and from a solar panel on the roof of the van. The circuit is used to power the interior lights, the water pump, the fan for the blown air heating and the TV. There are also two USB sockets for charging up phones.
There are a couple of control panels inside the van which are used to switch the heating and hot water between electric or gas (when on EHU then there’s no point in using up gas). The fridge automatically switches itself between power sources: from the engine battery when driving; from the 240v circuit when on EHU; or gas when off grid.
We did consider having a second leisure battery fitted to double up on our capacity, but having discussed with an auto electrician we decided to stick with the one battery. Some people also have an inverter fitted, which enables them to run 240v appliances (hairdryer, laptop charger) from the 12v circuit, but again we decided we probably wouldn’t need one.