When many van builders and designers are getting started on their Sprinter, Promaster or Transit shell they have a general idea of what the van will be like when complete. Based on how they want to use the van. Will it be a weekend warrior vehicle. Will it be for extended road trips with lots of travel. Or will the van be for living in as a nomad. Probably the result will be a combination. There will be long days spent driving, some days and nights spent in camp grounds, some boondocking and some overlanding. When planning the electrical system there are lots of choices. You may want a dc-dc charger to be able to replenish your batteries as you drive … https://www.canbat.com/product-catego... You may want solar panels to capture poser all day long … https://www.renogy.com/solar-kits/rv-... There a host of ways to generate power along the way. But most rely on storing the energy in 12 volt batteries. Either deep cycle or lithium … https://ca.renogy.com/200ah-12-volt-l.... No matter how you generate and store your power, getting back out to use has limited options. To use it as 12 volt you’ll be able to power your lights https://www.amazon.ca/Interior-Ampper..., your water pump https://ca.ecoflow.com/pages/portable... or your max air ceiling fan https://www.maxxair.com/. But 12 volt power has limitations. It can only power so much. If you’re vanlife dreams include extended periods off grid – almost like tiny home living – you’ll need a way to access a higher current to power an induction cook top https://www.thewaywardhome.com/induct... or water heater https://www.homedepot.com/p/Richmond-.... When shore power is not available you’ll need to change the 12 volt poser you have stored in the battery into 110 volt household current. You do that with an inverter. https://www.renogy.com/inverters/ - in video we explain how to install and test an inverter.