Mike Reyher
This is a basic overview of our current electrical system in our van to support off grid camping. There will be more details about the installation, operation, and performance of each major component in a later blog entry.
Objective
Our use case is "adventure camping" where we go out for a long weekend or a week or more. This is opposed to supporting "living in a van" longer term. The differences come down to what variety of power consumers/appliances we need to support. We decided we would avoid integrating a high capacity inverter at this time to simplify the installation and save money that would be spent on an inverter and more battery capacity. But we also want to leave ourselves in a good place to add one later should we decide we want to down the road.
Approach
There are tons of resources out there that tell you how to build an electrical system for a van conversion that you can find on YouTube and Amazon books. One great source I have enjoyed is Will Prowse's YouTube Channel and his book Mobile Solar Power Made Easy! on Amazon. Almost everyone says you should start with knowing the numbers around what your power needs are. You figure that out by looking up the power requirements of each "consumer" and then multiplying that by how long those consumers need to run in order to get down to how much energy needs to be generated and how much needs to be stored.
We start out in the sheet above listing out what things are going to consume power and what their power draw is in Watts and convert to amps by dividing by voltage, in this case 12 volts. Then we consider how long during a day they will be consuming to get how many amp hours we need since battery capacity for deep cycle batteries is measured/sold in amp hours. This gives us a rough idea of how much power we need to store, consume, and replace each day we are off grid.
Now we can consider our sources of energy. Alternator energy is reliable in that is is always there when the van engine is running but maybe we are not driving every day or far enough to top off the battery bank. Solar is great when the sun is out but cloudy days can lower the efficiency and so can not having the panels aimed directly at the sun which is hard to do when mounted flat on a van roof. You can see my educated guess in the table above and see that even accounting for fairly poor efficiency it looks like we can generate the power we need.
Update: 9/6/2024
In the real world, we don’t always move the van and have the chance to charge from the alternator so that takes the associated 75AH away from the “sources” section, which is significant. As a practical matter, we never ran out of power but there was plenty of anxiety about it and some management to be done which is not why we go camping. In some cases, we generated more energy from solar than anticipated but when the battery was full we had nowhere to store that energy. We also have a few more persistent consumers as we added an Internet router, Victron remote management and monitoring, and security cameras. These are pretty low power items but they are persistent (24x7). All this points to needing a larger battery and we recently upgraded from 100AH to 290AH of capacity that allows us to capture and store more energy both from solar and from the alternator while driving.
Plan
Most RVs, conversion vans, and even boats use a system built around a house battery bank that powers all the appliances and devices on-board. Power is then replaced by the vehicle electr
ical system, solar power, or often both sources. Power is distributed via a fuse panel and/or a switch panel that allows the user to turn on and off these various consumers.
Major Component Selections
Here is a listing of the major components we selected for our build to plug into the plan above.
Renogy DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT - Amazon Link
Why it made the cut: This unit combines the functions of a solar charge controller and a DC to DC charger to manage charging from the alternator in one package so it simplifies the installation. It's also cost effective as well. The quality of build could be better but so far it has worked as expected keeping us in power through our travels.
Victron Smart Shunt 500A - Link
Why it made the cut: Every van electrical system needs a way to monitor status and performance in order to make sure you have the power available to support keeping food cold, having enough light, running your fan, and charging devices. We picked this particular unit because not only does it do all of these thing, it also delivers this information to our smartphones via the Victron Connect App. This means we can check status whether we are in bed, or driving down the road, or hanging out at our campsite. It can also be extended as part of Victron's CX line to allow monitoring from anywhere with an Internet connection. You can read our more thorough review here.
Victron Cerbo GX - Link
Why it made the cut: The Cerbo GX takes system management to the next level because it allow you to monitor and control your system remotely via the Victron Remote Management Portal. We've written up a separate blog entry on the Cerbo GX here.
Newpowa 200W Monocrystalline 200 Watt 12V Solar Panel High Efficiency Mono Module - Amazon Link
Why this made the cut: We wanted at least 400 Watts of solar on the roof to account for cloudy days and the loss of efficiency of not aiming the panels directly at the sun. The units are highly rated and generate 200W per panel. They also happen to fit perfectly in front of the Maxxfan on the roof of our 148" WB 2020 Ford Transit. On top of that they are under the 25v limit of the Regnogy DCC50S so we can wire them parallel and get 400W of power. We use some special stainless steel brackets that allow us to be able to tilt the panels up for maintenance and cleaning.
Check out this other post for details on the solar installation.
Other Components
Here is a list of other components used in our electrical system implementation.
- BEP Battery Switch to select or turn off the solar panels - Amazon Link
- AM Solar 35mm Tilting RV Solar Panel Mount Set - Amazon Link
- Inline Circuit Breaker Reset Fuse Holder 12V-24V DC with Manual Reset - Amazon Link
- 12 Pack Battery Cable Ends Battery Cable Terminal UL Listed 4 AWG 1/2 Ring - Amazon Link
- 130 PCS Ring Terminals #10 Blue 16-14 AWG - Amazon Link
- Victron BatteryProtect (Smart 12/24V-65A) - Amazon Link
- Facon 3-1/2'' LED RV Puck Light Super Slim Under Cabinet Light Surface Mount Ceiling
- Dome Light with Push Switch - Amazon Link
- RV LED Directional Reading Light w/Switch | Black - Amazon Link
- Link Solar Weatherproof ABS Solar Double Cable Entry Gland - Amazon Link
- Conference Recessed Power Strip Socket 9.8Ft Cord,Desktop Power Grommet Power Strip with 2-Outlet & 2 USB Ports - Amazon Link
- Renogy 16Ft 10AWG Wire Copper Tray Cable one pair, Connect Charge Controller and Battery - Amazon Link
- 12V-24V DC Circuit Breaker 100A Fuse Inverter Fuse Holder with Manual Reset - Amazon Link
- 4 Gauge 4 AWG 15 Feet Red + 15 Feet Black Welding Battery Pure Copper Flexible Cable + 10pcs of 3/8" Tinned Copper Cable Lug Terminal Connectors + 3 Feet Black Heat Shrink Tubing - Amazon Link
- 14 Gauge (American Wire Ga) Tinned Pure Copper Red Black Duplex Sheathed Marine Boat Wire - Amazon Link
- NOCO GCP1EX 15 Amp 125V AC Port Plug Power Inlet with 12-Foot Integrated Extension Cord - Amazon Link
- Blue Sea Systems Common BusBars (100A-250A) - Amazon Link
- GENUINE OEM NEW replacement Connector & terminals for Motorcraft WPT-1037 WPT1037 and Ford 1U2Z-14S411-BLB 1U2Z14S411BLB - Amazon Link
- Maxx Air 00-07500K MaxxFan Deluxe with Remote - Smoke - Amazon Link
- Circuit Breaker Car Audio Solar Energy Inline Circuit Breaker Fuse Inverter With Waterproof Cover For Motor Auto Car Marine Boat (250A) - Amazon Link
- Blue Sea Systems ST Blade ATO/ATC Fuse Blocks - Amazon Link
- Blue Sea Systems Common BusBars (100A-250A) - Amazon Link