This is my worst area of knowledge. I just don't get how it all works and links together. A mate of mine always says, just think of electric as water. It flows in the same way. That only helps upto a point, then when things get complicated, I lose the flow! 😏
I started out from the opposite to most folk I guess. What did I want, then how do I get that. Basic was what came back after thinking about things. Lights to read/repair by, charging for laptop, camera, small stuff etc. Most of this can be charged whilst driving, so I bought 12v chargers for everything I could.
I first looked at a petrol generator. They are cheaper than an electric set up, take up less space and are proven reliable. They are generally also easy to fix in the field and require only an oil and filter change periodically. Downside, some noise whilst in use and carrying petrol. I liked this idea and I definitely liked the purchase price. Plus, I'd used big diesel generators in remote places many times and knew their issues. Around £300 gets you a 1Kva petrol generator from a major manufacturer. They weight around 16kg plus 10 litres of petrol at 10kg., so a max weight of 26kg.
I looked at the solar option. This is all the rage these days, with the argument it's better for the planet etc etc… I highly dispute that after looking into the initial build, lifespan and eventual disposal of each part. Yes, they are 'clean' whilst in use, but at material sourcing, manufacture and disposal, they are a nightmare.
Lifespan is also an issue. Every single electronic gadget I've used in remote places has broken, which left a dead weight on vehicles and a hole in problem solving. The purchase price is also painful. Around £800 - £1000, with lots of parts to buy and bolt into the truck. The positive is its supposed to be an upfront purchase price only, then years of service reducing any costs. Time will tell I guess.
An in between option is a power pack. These are all the parts of the solar option, but as a standalone box that is recharged by either 240v mains or solar panel. They come in at around £700 for the box and weigh around 15kg. Biggest issue with these is redundancy. Once they fail, they are a dead weight and you can't just replace a component.
Weight is also an issue. The 100amp lithium battery weights 14kg. Solar Panel 14kg, the Victron solar charger and DC DC charger weighs around 4kg, the fuses, wiring, switches, monitors etc all come in at around 8kg. So a rough total of 40kg.
That's a considerable difference to a petrol generator, even with extra fuel, and will effect the vehicle overall fuel usage over time. That's an added cost that is not factored into any calculation I've found for the cost of these systems so far.
My final choice was a mix of three options.
1. Mains battery to leisure Lithium battery via DC DC charger
2. Solar panel to Lithium battery via solar controller
3. 240v Hook up using extension cable + connector
The thinking behind this choice is to have multiple systems in one vehicle, mainly to build in some redundancy as well as having a totally separate system which can be linked to a replacement power source if needed and/or available. A lot of charging can be done on the move at 12v, the rest when parked up.
The key failure point of the whole setup is the lithium battery. That is the only single point. At least these can be replaced most places these days. And if it all fails, I'll just find another battery or a petrol generator, plug it in when needed and stick to that!
Installation is in a separate post, but the basic plan is below.
