Camper Van Solar System Guide (A DIY Setup Tutorial)
Solar panels are the perfect complement for a camper van electrical system. But while harnessing the sun’s rays can help you achieve energy independence, building a solar system for van life can be daunting. There’s solar theory, some math, and lots of wiring involved when you’re ready to install everything together.
This solar guide will get you through all this and cover all the details you’ll need to install a camper van solar system. We include solar panel recommendations, wire and fuse sizing calculations, wiring diagrams, and much more. You don’t need to be an electrical engineer to put together a safe and functional PV system, and this post will prove it to you.
- Chapter 1: Solar Panels
- Chapter 2: How Much Solar?
- Chapter 3: Series vs. Parallel Wiring
- Chapter 4: Charge Controllers
- Chapter 5: Solar Wire Sizing
- Chapter 6: Fuses & Breakers
- Chapter 7: Mounting Solar Panels
- Chapter 8: Install Guide
If you’re ready for the challenge, we’re here to help. Let’s get to it!
Disclosure: As an Amazon Associate, this site earns from qualifying purchases. Though we may earn a commission, the price you pay always remains the same.
Solar Panels
1.1 – Rigid vs. Flexible vs. CIGS Solar Panels
When building a solar system for a camper van, there are two types of solar panels to choose from: rigid and flexible. If you already know which type of panels you want, you can skip to Chapter 2 (How Much Solar?). Otherwise, we compare the two types, including the new flexible CIGS models, and argue why rigid panels are (most likely) what you want.
Rigid Panels
- Physical Durability: Best. The aluminum frame and tempered glass top layer make the panel extremely damage-resistant.
- Lifespan: Best. Durable construction and the ability to vent hot air behind the panel equates to the longest lifespan, on average.
- Efficiency: Best. Smallest footprint per watt. Panels stay cool with proper venting, which maximizes efficiency.
- Price: Best. Lowest $/watt. Ideal for budget builds.
- Installation: Worst. Must screw panels onto the roof or on a roof rack.
Flexible Panels (Standard)
- Durability: OK. More expensive panels come with an ETFE top layer for greater scratch & impact protection.
- Lifespan: Worst. Plastic construction with no way to vent out hot air means panels often last <2 years on a camper van.
- Efficiency: Worst. Solar cells easily overheat, reducing efficiency and generating hotspots.
- Price: Middle. Medium level $/watt.
- Installation: Best. Easy installation with only tape. No screws are required.
Flexible Panel (CIGS)
- Durability: Good. The protective top layer and ultra-flexibility make these panels stronger than standard flexible panels.
- Lifespan: Middle. New technology means not much data. It has better construction than standard flexible panels but is still prone to damage and overheating.
- Efficiency: Middle. Outperforms other panels in partial shading, but low efficiency means CIGS panels are ~20% larger. No venting option means panels can still overheat and develop hotspots.
- Price: Worst. Most expensive $/watt.
- Installation: Best. Only tape is required. No screws.
Comparison Table
The table below compares the most important differentiating factors between rigid and flexible panels. We omit CIGS panels in this table, but we review them after.
Rigid Panel1 | Flexible Panel2&3 | |
---|---|---|
Efficiency | ~22%2 | ~15-23%4 |
Durability | Strong (tempered glass top layer) | Weak (prone to scratches) |
Overheat? | No | Problematic |
Weight | 14.1 lb (6.4 kg) | 5.3 lb (2.4 kg) |
Thickness | 1.4 in (35 mm) | 0.1 in (3 mm) |
Less Visible | / | Yes |
Installation | Requires drilling holes | VHB tape only = OK |
Price ($/watt) | Cheaper | More expensive |
Better Deal? | Yes! |
Table Footnotes:
1. Renogy 100W rigid panel
2. Standard, not CIGS
3. Renogy 100W flexible panel
4. See efficiency appendix
5. Renogy warranty information
6. Renogy 100W rigid panel
Key Takeaways
- Efficiency: Flexible panels are 10-25% less efficient (in real-life scenarios) at converting sunlight into usable energy. The biggest reason for this is that solar cells become less efficient the hotter they get, and flexible panels, with their plastic layers, cannot dissipate heat as well as rigid panels. This means you will need more watts (larger panels) if you choose flexible solar panels.
- Lifespan: Flexible panels, with their plastic protective layers, are more prone to physical damage (e.g., scratches and cupping) and overheating (e.g., hot spots).
- Installation: Due to their lightweight nature, flexible panels can be mounted on a van’s roof using regular duct tape. Rigid panels, however, should be screwed down, which requires drilling holes.
- Stealth factor: Flexible panels are less than 1/10th the thickness of rigid panels, making them ideal for stealth campers.
1.2 – Best Solar Panels For Camper Vans?
“Which type of panels should I use for my van conversion” is often asked question. And the answer depends! Below, we theorize three types of van lifers and provide a solar panel recommendation for each.
Situation 1: Prioritize Durability, Longevity, & Cost Efficiency
These are people who value solar panels that are built tough and can withstand the day-to-day grind of van life. They also want solar panels that won’t suddenly break down, overheat, and/or develop hotspots (as flexible panels tend to do). Lastly, cost and space efficiency are critical for them. They want to spend the least ($/watt) and want the most watts production per square footage of roof real estate.
Solution: Newpowa 100W rigid solar panel
Situation 2: Prioritize Easy, Non-Invasive Install
These are people who absolutely don’t want to drill holes in their van’s roof. They prioritize an easy solar panel installation using tape instead of screws. They also like to be more discreet and prefer panels with a thinner profile.
Solution: BougeRV 100W ‘Arch’ flexible solar panel
Situation 3: Prioritize Easy Install, Partial Shading Efficiency & Not Cost Sensitive
These are people who, like those in SItuation 2, prioritize an easy, non-intrusive solar panel installation. However, money is not a concern and they are willing to pay a considerable premium for flexible solar panels that are more durably and substantially more productive in partial shading.
Solution: BougeRV 100W “Yuma” CIGS Flexible Panel
$89.99
|
$111.98
|
$279.99
|
1.3 – Solar Panel Recommendations
We recommend rigid solar panels for the vast majority of camper van conversions. With a robust tempered glass top layer, rigid panels are more resilient to the daily rigors of van life and last considerably longer than flexible panels in the real world (we’ve seen several flexible panels overheat and go bust after less than a year of use).
If you are worried about using screws and having water leaks, you can either use a roof rack or follow our solar panel mounting guide. 5+ years and NO LEAKS.
Our experience: We installed two large Newpowa solar panels on our camper van, and they have been working for us non-stop for the past five years. Our panels have frequently brushed up against low-hanging branches and have been covered in dirt and bird poop. But after a quick wipe-down, our panels still look like new. Newpowa panels tend to be the most affordable ($ per watt) compared to other brands, but you should double-check on Amazon.
If your roof dimensions can fit them, get the larger 200W panels, instead of the smaller 100W version. These are more space-efficient and you can never have too many watts. And whichever panels you get, make sure they utilize the latest 9BB/10BB technology.
We use Newpowa panels on our van, and they've been working great for over five years of van life. Newpowa also tends to sell the lowest cost panels, dollar-per-watt.
To learn more, read our more thorough solar panel comparison for campers.
How Much Solar?
It is critical to calculate the minimum solar array wattage suitable for your camper van. The more demanding an electrical system is, the more watts of solar that is required. In our van, we have 360W (2 x 180W panels) of solar, which has been perfect at supplying our electrical needs for the last five years.
A common misconception when sizing a solar system, however, is that โsolar panels power electrical devices.โ This leads people to only look at the size of their electrical loads and solar watts. But this view is incomplete because it doesnโt factor in battery size.
Example: Suppose you have a large electrical system and installed a correspondingly large solar system. But if your batteries are undersized, they wonโt be able to sustain the large electrical load in the evening when the solar panels are unproductive.
Over the years, weโve seen this situation more often than you would think in actual camper vans. So, whatโs a better way of going about this? Instead of sizing the solar panels to your electrical load, think about sizing your solar panels to your batteries and sizing the batteries to the load. In this way, the batteries will be able to support the loads during the daytime AND night, and the solar panels will be able to recharge the batteries sufficiently the next day.
Consequently, we recommend the below two-step process for sizing your solar system.
- Step 1: Calculate battery size based on electrical load (use battery calculator)
- Step 2: Calculate solar size based on battery size
2.1 โ Solar Calculator
Once youโve used our battery calculator to size your battery bank, download our solar calculator (below) to identify your ideal solar wattage size. If you fill in all the fields, the calculator will ALSO recommend the correct size wires, charge controller, and fuses.
2.2 โ Battery/Solar Table
We think our solar calculator is pretty nifty. But if you’d prefer not to download any files, refer to our solar size table below. If you have a 12V battery bank, use the ratios below to determine your solar array wattage size.
- Lithium batteries: Use a 1:1 ratio of battery bank Ah to solar array watts.
- AGM batteries: Use a 2:1 ratio of battery bank Ah to solar array watts.
12V Battery Size (Ah) | Solar Watts (with AGM) | Solar Watts (with Lithium) |
---|---|---|
100Ah | 50W | 100W |
200Ah | 100W | 200W |
300Ah | 150W | 300W |
400Ah | 200W | 400W |
Have a 24V system? Use a 1:2 ratio for lithium batteries and a 1:1 ratio for AGM batteries.
Our Opinion: The table above only suggests the minimum solar array size that would meet your power needs. If you have available space on your roof, adding more panels is a good option. We have 300Ah of lithium batteries and have a 360W solar array.
Series vs. Parallel Wiring
Like wiring multiple batteries together, you can also connect multiple solar panels together in either series or parallel. By choosing which method to wire your panels, you can manipulate the volts and amps that are sent to the solar charge controller from the solar panels. The diagram below shows how the two styles differ when wiring two solar panels together.
Wiring panels in series is relatively simpler, while parallel wiring involves additional components like branch connectors and, potentially, solar fuses.
Although both wiring methods will yield the same total watts under the same intensity of sunlight, there are subtle outcome differences you should know to help you make an informed decision as to which approach to use. Our table below highlights these differences.
Series | Parallel | |
---|---|---|
Total current (A) | Remains same | Adds up |
Total voltage (V) | Adds up | Remains same |
Wire size | Smaller | Larger1 |
Installation | Easier | More complex2 |
Performance in shade | Wose | Better3 |
Table Footnotes:
1. Most times larger, but not always.
2. Requires branch connectors & (sometimes) solar fuses.
3. Better wattage output in partial shade
3.1 โ Series Wiring
How to wire? To wire panels in series, the negative line of the first panel connects to the positive line of the second panel. Then, the negative line of the second panel connects to the positive line of the third panel. And so on. In the end, you will have one available positive line (from the first panel) and one available negative line (from the last panel) to connect to the solar charge controller.
The result of wiring multiple solar panels in series is that the overall solar array voltage (V) is equal to the sum of the output voltage of each individual panel. The voltage increases but the total current (A) stays equal to the current output of a single panel.
- Voltage (V): Adds up
- Current (A): Stays the same
Pros & Cons
Wiring solar panels in series is a great choice if you prioritize installation simplicity (fewer solar components) and cost reduction (thinner electrical wire). The biggest drawback is that solar arrays wired in series perform worse in partial shade compared to panels wired in parallel.
Pros | Cons |
---|---|
One faulty panel stops the charging | Less efficient in partial shading |
No in-line fuses required | One faulty panel stops the charging |
Thinner solar output wire |
3.2 โ Parallel Wiring
How to wire? To wire multiple solar panels in parallel, connect all the positive lines together and all the negative lines together using branch connectors.
- If you have two solar panels, use a 2-to-1 branch connector.
- If you have three solar panels, use a 3-to-1 branch connector.
The result of wiring multiple solar panels in parallel is that the total current (A) produced by the solar array is equal to the sum of the output current of each individual panel. The current increases, but the total voltage (V) stays equal to the voltage output of a single panel.
- Voltage (V): Stays the same
- Current (A): Adds up
Pros & Cons
The most significant benefit of wiring solar panels in parallel is that the array is more efficient at producing power when partially shaded. This is a very real benefit because your camper van will often be parked in partially shaded environments. Whether it’s shade from trees, mountains, buildings, or electrical poles, your solar array will experience lots of shade. So, wiring the array in parallel to be more efficient in shaded situations may be a smart choice.
Pros | Cons |
---|---|
More efficient in partial shade | Branch connectors required |
A faulty panel does not stop charging | Solar fuses required |
Thicker wires (maybe) required |
3.3 โ Our Recommendation
Which wiring method do we recommend? It depends on how many solar panels you are planning to install.
2 Panels Only? Wire In Parallel
If you only have two panels, wiring in parallel is the best choice. Not only will these panels perform better in partial shade, but having only two panels ensures that you do not need MC4 in-line fuses and that you won’t require needlessly thick wires to connect them to your charge controller. Skip to Chapter 6 (Fusing A Solar System) to learn more.
In our van: We installed two 180w solar panels and wired them in parallel
3+ Panels? Wire In Series
For three or more solar panels, consider wiring the array in series. Wiring in series allows you to skip the in-line fuses and bulky 3-1 branch connectors.
Solar Charge Controllers
Solar charge controllers are a vital component of every camper van’s solar system. These controllers take power (with a widely fluctuating voltage) produced by the solar array and regulate the incoming voltage so that the batteries can accept the power for proper charging. Without a charge controller, the solar panels would quickly overcharge and destroy the batteries.
Example: Think of your brain as the charge controller when eating. As you eat, you become more full, and your brain tells your body to slow down. When you’re full, your brain tells you to stop eating. Without the brain telling you when to slow down and eventually stop eating, you’d continue to eat and eat until…bad things happen. The same would be true for a battery connected to a solar panel without a charge controller.
4.1 โ What Size Solar Charge Controller?
Charge controllers come in different sizes (amp-ratings). The more watts a solar array produces, the larger the charge controller will need to be. Based on your solar array’s total wattage, use the list below to find your ideal charge controller size.
- 0-220W: 15A controller
- 220-440W: 30A controller
- 440W-700W: 50A controller
- 700-1000W: 70A controller
Our Opinion: We love our Victron-branded charge controller. All models are Bluetooth-enabled and send solar harvesting stats directly to smartphones via the VictronConnect app. Read our Victron charge controller review to learn more.
4.2 โ Why Victron Solar Charge Controllers?
Although pricier, Victron charge controllers are the best option for camper vans. This is because they are one of the only brands manufacturing Bluetooth-enabled controllers. With their VictronConnect app, you can easily view vital solar statistics via the Victron app and keep an eye on your daily solar production.
Through our smartphones, we can also update the controller’s settings, switch the device off for maintenance, and even view a 30-day history of solar harvesting data.
To learn more, check out our Victron solar charge controller review.
Solar Wire Size
Using the correct wire size for your solar system is critical because if the cables are too thin, you risk pushing more electrical current (Amps) than the wires can handle. This overheats the cables and can eventually be a fire hazard.
This chapter will help you identify the wire sizes you’ll need to connect the solar panels to the charge controller and from the charge controller to the batteries.
Note: This chapter provides a condensed version of our solar wire size post. For more details and sizing justification, please read that post.
When calculating solar wire sizes, there are two wiring sections to consider. Sometimes, these two sections will use the same wire size, and sometimes, they will not. This post will help you calculate the correct gauge size for BOTH parts.
- Section 1: Between the solar panels and the charge controller
- Section 2: Between the charge controller and the bus bars
Where are the batteries? We will connect the charge controller to bus bars, which are power collection and distribution centers. This is where the solar system terminates. You can learn how to wire the bus bars to the batteries in our 12V system guide.
Section 1: Wire Size From Panels To Charge Controller
This section will cover how to calculate the solar wire size you’ll need to connect the solar panels to the charge controller.
Step 1: Calculate Solar Array Maximum Amps
The first step is to calculate the maximum amps the solar array is capable of producing. To do this, you will need to know:
- The short circuit current – Isc(A) – of your panels
- If panels are wired in series or parallel (for multiple panels only)
For panels wired in series: The maximum amps produced by the array is only the Isc(A) of one of the panels. This is because in series connections, the voltages of each panel add up, but the amps do not.
For panels wired in parallel: The maximum amps produced by the array is the sum of the Isc(A) of each panel. This is because in parallel connections, the amps of each panel add up, but the voltages do not.
Example: We have two solar panels wired in parallel. The short circuit current – Isc(A) is 11.75A for each panel. Therefore, the total output current is 23.5A (11.75A + 11.75A).
Step 2: Include NEC Safety Factor
Take the amps you calculated in the previous step and multiply by 1.56. This is to comply with National Electric Code (NEC 690.8), which states:
- 25% must be added to the total amps to account for solar derating
- Another 25% must be added to the total amps when sizing conductors
By multiplying your amps by 1.56, you are accounting for both 25% increases.
Example: Our two solar panels can output 23.5A. After multiplying by 1.56, we get 36.66A.
Step 3: Select (Section 1) Wires
Based on the amps you calculated in Step 2, locate your amp range (table column 1) and identify your ideal solar wire size from the table below.
4mmยฒ |
6mmยฒ |
10mmยฒ |
Note: We only verify the safety of these amp ranges when used with Windynation solar cables. We have spoken with their engineers, who have verified these amps are for continuous current loads.
Section 2: Wire Size From Charge Controller To Bus Bars
This section covers the solar wire size you’ll need to connect the charge controller to the bus bars.
Step 1: Size Your Solar Charge Controller
The first step is to know the ampacity rating of your solar charge controller. The controller size you’ll need depends on the maximum wattage output of your solar array.
For more information, scroll back up to our charge controller sizing section.
Step 2: Include NEC Safety Factor
Once you have your charge controller, take its ampacity rating and multiply by 1.25. This is the 25% safety factor mandated by the NEC for wire sizing.
Example: We have a 30A charge controller for our 360W solar array. When we multiply 30A by 1.25, we get 37.5A.
Step 3: Selection (Section 2) Wires
You can now determine the solar wire size you need to connect the charge controller to the bus bars (Section 2). To do this, take the amps you calculated in the previous step and identify the correct wire size from the table below. The amps you calculated should fall within the range listed in column 1.
Amp Range | Charge Controller |
---|---|
0-30A | 10 AWG Wire |
30-55A | 8 AWG Wire |
55A-115A | 6 AWG Wire |
115-150A | 4 AWG Wire |
The below wires (8 AWG to 4 AWG) are Windynation wires, which we trust to carry the ampacity ranges we list in the above table. The 10 AWG wire below is an Ancor marine-grade wire, a brand that we also trust.
6mmยฒ |
10mmยฒ |
16mmยฒ |
25mmยฒ |
Example: From the previous step, we calculate 37.5A from our 30A charge controller. Using the above table as a reference, we should use 8 AWG wires to connect the charge controller to the bus bars.
Fuses & Breakers
When installing fuses and breakers into a solar system, there are three areas to be aware of.
- MC4 in-line fuses before branch connectors (parallel wiring only)
- Solar DC breaker after solar panels
- DC breaker after charge controller
Refer to the below graphic to locate each of the three areas.
We take a look at each of the three sections below.
MC4 In-Line Fuses
Solar fuses only need to be used when three or more solar panels are wired in parallel. You do not need a solar fuse if your array is wired in series. The size of the MC4 solar fuse you need equals the ‘maximum series fuse rating’ listed on your solar panel.
You can often locate the “maximum series fuse rating” on the solar panel’s online product page. Below is an example we found on Amazon for a standard 100W solar panel. In this situation, you would use a 10A MC4 solar fuse with this panel.
If you already know the maximum series fuse rating for your solar panels, select your required fuse from the table below.
Solar DC Breaker After Solar Panels
Not only does this DC breaker protect your wires and connected devices from unforeseen surges, but you can also flip the breaker and disconnect the solar system during maintenance.
To select the ideal breaker for your system, identify the total short circuit current (Isc) produced by the array, then multiply by 1.25 (NEC safety factor) and multiply by 1.25 again (for continuous current). Then, round up the result to the next available breaker size.
Example: Two 200W Newpowa panels wired in parallel have an Isc of 22.94A (11.47 x 2). Then, 22.94A * 1.25 * 1.25 = 35.8A. Rounding up means a 40A breaker is appropriate to use.
A DC Solar Breaker is used to protect the solar wires between the panels and the charge controller. It also provides an easy way to disconnect the panels during regular electrical maintenance.
DC Breaker After Charge Controller
The size of the DC breaker after the charge controller is related to the amp rating of the charge controller itself.
To calculate the breaker size, take the amp rating of the controller and multiply it by 1.25. Then, round up the result to the next breaker size.
For Example: If you have a 30A charger controller, multiply 30A * 1.25 to get 37.5A. Rounding up means a 40A breaker is appropriate to use.
Fuse Summary
By installing the three different fuses discussed above, your wiring system may look similar to the diagram below.
Check out our solar fuse guidelines post to learn more.
Mounting Solar Panels To Roof
Before installing any solar panels on your camper’s roof, it’s essential to think about the following two issues.
- Solar panel layout – How will you arrange the solar panels on your roof? Horizontally or vertically?
- Direct mount vs. roof rack – Will you install the panels directly to the camper’s roof? Or install the panels onto a roof rack instead?
We discuss each of these two sections below.
Solar Panel Layout Planning
There are two ways to orient your solar panels on the roof: horizontally (left to right) and vertically (back to front). The two main factors determining your panel’s orientation will be the dimensions of your vehicle’s roof and the individual dimensions of each panel.
Refer to the diagram below for two solar panel layout examples.
Creating an accurate solar panel layout plan to scale isn’t tricky. But you will need the exact dimensions of your camper van’s roof and the dimensions of the solar panels. Once you have that, you can use any paid or free drawing software to see how the solar panels look on the roof. For more information on how to do this, we recommend reading the following posts.
Direct Mount vs. Roof Racks
The second important question to answer is ‘how’ you will attach the solar panels to your camper van’s roof. The most common choices are to mount the panels directly to the vehicle’s roof or attach the panels to a roof rack.
Direct Mount
Involves screwing the solar panels directly onto the roof. This method gives the panels the lowest profile and attracts the least attention, which is beneficial for stealth campers. But the downsides are that you may have potential water leaks in the future and that removing the panels for maintenance is a hassle.
Roof Rack
If done right, roof racks can be installed without drilling any new holes in your camper’s roof. Then, attach the solar panels to the roof rack. There is no potential for roof leaks, and you can easily remove the panels when needed. The downside is that the panels will be elevated slightly more off the roof, bringing more public awareness.
Our Opinion: We installed solar panels directly to our vanโs roof. Theyโve worked great, look streamlined, and we havenโt had any leaks (yet). But if we could do our build again, weโd spend the money on a low-profile roof rack instead.
We used a combination of 3M VHB tape and Butyl tape to ensure that our solar panel installation is not only secure but also waterproof. To learn more, check out our solar panel mounting post.
Solar Installation Guide
In this last chapter, we show you how to wire a solar panel system in a camper van and tell you exactly which components you need. The diagram we will follow works for solar solar arrays that are wired in series with a maximum wattage output of 440 watts. If you plan to install a solar system that matches these details, you can directly copy the diagram below.
Solar Panels
If your camper van’s roof can fit them, going with larger 200W panels is better than the more common 100W panels. They’re more space efficient and less drilling is required. We use Newpowa solar panels on our van and they’ve been working great for the past five years. Newpowa panels tend to be the more affordable on Amazon ($/watt), but you should shop around and compare prices.
We use Newpowa panels on our van, and they've been working great for over five years of van life. Newpowa also tends to sell the lowest cost panels, dollar-per-watt.
Solar Cables (With MC4 Connectors)
We discussed how to calculate your ideal solar wire size in Chapter 5. But if you only intend to install a single panel, or are wiring multiple panels in series only, you can use 10 AWG solar cables to connect the solar panels to the charge controller.
We recommend Windynation solar cables because we trust their quality and their marketed ampacity ratings. These cables are made in the USA with robust polyethylene insulation jackets that resist UV rays.
These cables already come with MC4 connectors crimped onto the wire ends, so you don’t need to buy any other solar components to complete the wiring. It’s plug and play ready.
Pure copper wire encased in a chemically crosslinked polyethylene jacket for UV/sunlight resistance. Manufactured in accordance with National Electric Code protocol and UL tested/certified. 100% made in the USA.
Note: You do not need MC4 connectors on both ends of the wires. Cut the male connector off the red wire and female connector off the black wire and insert the wire ends into the solar DC breaker.
Solar Entry Gland
This entry gland attaches to the roof of your van and protects the solar cables as they enter the vehicle from the outside. The entry gland also protects against water leaks into the van.
This solar entry gland protects the solar wires as they pass through the van's roof to the interior. If sealed properly, a solar gland also prevents water leaks from entering the camper.
Solar DC Breaker
Not only does a DC breaker protect your wires and connected devices from unforeseen surges, but you can also flip the breaker to disconnect your solar system to conduct maintenance. If you are following our solar diagram and using 10 AWG solar cables, a 40A breaker will be correct.
A DC Solar Breaker is used to protect the solar wires between the panels and the charge controller. It also provides an easy way to disconnect the panels during regular electrical maintenance.
Solar Charge Controllers
We show you how to calculate the ideal charge controller size for your solar system in Chapter 4. Our recommend 30A charge controller below is appropriate for solar arrays up to a maximum of 440 watts.
We love this Victron controller not only for it's high quality build, but the Bluetooth feature is rock solid. The Victron smartphone app provides an amazing interface to monitor all your solar data. This 30A charger is good for solar systems up to 440W (for 12V batteries).
Electrical Wire (Charge Controller To Bus Bars)
With a 30A solar charge controller, 8 AWG wire is the ideal size to use. For a detailed explanation, read our solar wire size guide.
We always recommend using Windynation cables. They’re made in the USA, certified for their ampacity ratings, and ultra-flexible.
We like WindyNation wires for their ultra flexibility (high strand count) and tough EPDM rubber insulation. We use these 8-gauge wires for wiring the solar charge controller to the bus bars.
Circuit Breaker
The circuit breaker protects the charge controller output wire (to the bus bars) from overheating and catching on fire. If you are using our 30A charge controller, this 40A breaker is correctly sized.
Lug Connectors
The Sanuke assorted lug set is what you need. If you follow the rest of our camper van electrical system guide, you’ll know that we frequently refer to this set because it contains lug terminals for a a wide range of wire sizes (2-8 AWG) and ring sizes (1/4″, 5/16″, and 3/8″).
Save money with this convenient lug terminal set. It covers 12 different lug sizes from 2-8 AWG wires and M6-M10 ring diameters. Heat shrink is also provided.
FAQ
Surprisingly, you do not need a huge garage full of random tools to build your own camper solar system. You should be able to complete most of the installation process with a wire cutter/stripper, and MC4 assembly tool, and a drill.
If you value being energy-independent and getting off-grid, solar panels are worth the investment. If you are on a tight budget, we provide a solar solution that costs less than $450.
If you follow our solar sizing guide, we don’t think tilt panels are worth the money and trouble. Our solar panels do not tilt, and we are getting PLENTY of solar power into our batteries each day.
Conclusion
We hope this camper van solar installation guide was useful for your van conversion project. Although building a solar system can appear daunting, we’re confident that you can install your own DIY system by going slow and doing your homework ahead of time.
If you have any questions, please comment in the below section.
Lastly, be sure to check out our eBooks with helpful wiring diagrams. They are a valuable resource and are all completely free to use.
Happy building!
Appendix & Footnotes
1. Flexible Panel Efficiency
New flexible solar panels tout their efficency data as equal to rigid panels. The BougeRV Arch Panel claims to be 23% efficient. However, we have a difficult time trusting this lab data in real-life scenarios because:
- Studies have shown solar panels lose efficiency as the solar cells get hotter, and
- Flexible panels get hotter than rigid panels due to the inability to dissipate heat effectively.
On a camper van, solar panels spend many, many hours under intense sunlight. In our experience talking with other van lifers, flexible solar panels haven’t held up nearly as well as rigid panels. Flexible panels get substantially hotter, develop hotspots, and eventually burn out at much faster rates.
The reality is that we’re not always traveling in the cool Rocky Mountains or Casacades where flexible solar panels can stay cool. We’re always driving through the hot deserts and coastlines. This should also be considered when selecting the best type of solar panel for your camper van.
2. Windynation Electrical Wires
There are A TON of different electrical wires sold online. Some of these wires are good quality, but some are questionable junk with foreign manufacturers facing no real accountability for misleading marketing. Sifting through all the varieties is a headache. We know, we did it ourselves!
To keep this post simple and safe, we only recommend Windynation-branded solar cables. Windynation is an American-based company, and every wire is UL-tested and 100% made in the USA. In other words, we trust their listed wire ampacity ratings, which, in turn, keep our solar system safe.
We inquired with Windynation support staff regarding the ampacity ratings of their wires and below is an excerpt of their reply.
“Attached is our Certificate of Conformance for our cable. The ampacity is indeed continuous in open air (room temp).”
Windynation Support Staff
Their certificate of compliance is the perfect resource because it verifies Windynation’s own wire ampacity ratings in a continuous current environment instead of relying on a generic 3rd party table that encompasses many different wire grades. We will refer to this certificate when recommending your (section 2) solar sizes.
We also like Windynation because the American-based company manufactures premium-quality pure copper wires encased in a tough EPDM rubber insulation jacket for high-temperature resistance and ultra-flexibility. Lastly, these wires are assembled in the USA, which we prefer because this gives us greater reassurance that we can trust the wire quality and their verified ampacity ratings.
“The cable uses copper mined in Canada and is indeed extruded / stranded in the USA. The copper strands are bundled and wrapped in a paper separator that is then encapsulated in an EPDM rubber jacket.”
Windynation Engineering Staff
3. Graphic Credits
Van Conversion Essential Bundles
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