SOLAR TILTING GUIDE
Welcome to the ultimate solar tilting guide! Your one stop destination for everything you need to know about tilting your panels to boost your solar efficiency on your RV, van, trailer, or boat. As you probably already know, tilting your solar panels is a proven method to increase your power output by as much as 40%. But should you invest the time and effort to install a tilting system or simply throw an extra panel on the roof to meet your needs? All of that and more will be covered in this guide. Here is a quick breakdown of covered topics:
Why you should NOT tilt your panels
Why you SHOULD tilt your panels
Types of Tilting Systems
Why you should NOT tilt your panels
Let’s be honest, tilting your panels is not for everyone. There are a lot of good reasons to leave your panels flat and not bother with them. Here are a few questions to ask yourself when trying to make this decision:
Do you plan on using your panels in the winter?
Do you have a secondary vehicle to scoot around in?
Do you stay in one spot for more than 2 days?
Do you rely heavily on your solar system?
Is your rooftop accessible?
Do you use your solar system when your camper is not in use?
If you are a weekend fair-weather camper, then tilting your panels may not be the right solution for you. Also, if your camper is your primary vehicle and you use it to get around on a daily basis, it may be a lot of work to tilt your panels every day. From my experience, It’s not worth the effort of tilting your panels unless you know you’re going to be parked in one spot for at least 3 days. Finally, if you don’t rely much on your solar system or if your rooftop is completely inaccessible you may just opt for a flat mount setup.
Why you SHOULD tilt your panels
Since you’re on this page, though, I’m assuming that you are more of a long term (3+ day) camper, your camper is not your primary vehicle, and you would like the ability to camp in the winter. If you answered yes to two or more of the above questions, you should probably consider adding a tilting system to your solar set up. I won’t dwell on this subject too long before we dive into the nuts and bolts, but I will give a quick overview of our set up and why we chose to opt for a tilting system:
My wife and I have been full time RVing now for 3 years in our 33’ class A. We both work full time remote and depend very heavily on our solar system every day to meet our demands. We also are strictly boondock campers, finding free federal and state land to park on wherever we go and typically staying for 2 weeks at a time. So far this year we’ve paid for campsites a total of 4 nights, and this is all possible because of our solar system. Not a bad way to live on the cheap! We have an 800W system with 4.8 kW-h of lithium batteries. I designed the 4 Way Solar tilt system to ensure we would meet our power demands even in the most extreme of circumstances (winter camping with poor weather). I also wanted to make sure that our tilt system didn’t limit where we could park, because the last thing we wanted when pulling into a new boondocking site was to be limited in our choice of camp sites due to a 1 or 2 directional tilting system. It’s all about versatility! We’ve been able to say yes to some truly amazing camp sites simply because we could tilt in any direction and continue to work full time.
That’s enough about us for now, let’s jump into the technical aspects of tilting your solar panels!
Most of what you need to know about tilting your panels can be summed up in the following chart:
Note: This chart is based on estimates from several years of observed data while travelling in the Western US from Canada to Mexico.
This graph shows you the effect of tilting at different times of the year during solar noon. At the summer solstice you can see that tilting doesn’t have nearly as big of an impact as it does in the winter (750 vs 700 in summer and 700 vs 500 in winter). This is because the sun is around 30° lower in the sky in the winter, so tilting has a much more substantial impact.
Also on this graph, you can see the effect tilting has in terms of daily power produced in kW-h. This is the metric that most people will use to measure their power usage. For reference, the average American household uses around 27 kW-h of power per day. As minimalist RVers, though, we can get by on far less. Personally, I have found that about 3 kW-h of power per day is enough for 2 adults to live and work full time. We can get by on far less in times of bad weather, though, by running the fridge & water heater on propane instead of electric. At times when a lingering rainstorm blocks the sun for a few days, we’ve been able to stretch 3kW-h to about 3 days when necessary.
I could get into much more technical details about zenith angles and calculating exact angles based on latitude, but instead I’ll keep it short and to the point. If you’re interested in a more in-depth and technical analysis of this topic, check out www.pveducation.org.
Types of Tilting Systems
When deciding which type of system you should go with for your RV solar tilt system, you basically have 4 options available to you on the market:
Single Axis Tilt systems
Dual Axis Tilt systems
4 Way Tilt Systems
Powered Tilt System
The first two are pretty self explanatory; these tilt systems allow you to manually tilt your panels in 1 and sometimes 2 directions. Most of them work in a similar fashion, with a screw knob and wing nut securing the 4 corners of your panel. These allow for a quick release of one side of the panel, so that a stilt can be inserted to prop up the panel into the tilted position. There are quite a few different suppliers on the market ranging from $50 - $130.
A 4 Way Tilt system works in a similar fashion to the 2 way tilt system, but offers much more versatility in that it gives you the ability to tilt your panel in all 4 directions. This will give you the most amount of freedom to orient your rig in any direction you see fit. This system is slightly more complex than the 2 way tilt system, and has 4 additional brackets and 4 additional screw knobs to allow for the increased articulation. Once installed, though, it is just as easy to tilt and stow as any other manual tilt system. 4 Way Solar is currently the only provider of a 4 way tilt system, and holds a provisional patent over this design. Check out our shop, to see our products and current pricing.
Finally, there are also powered tilting systems that use an electric motor to tilt the panels for you. This route offers the most convenience, but also the largest price tag. Typically, they only tilt in one direction, but can be tilted and stowed simply by the push of a button! This may be a good option for those who are intimidated by climbing up on their roof, or simply don't want to deal with the hassle of manual tilt. A quick warning, though, these will cost you between $500 - $600 per panel, and will only tilt to one side of your rig. If interested, check out https://www.solarvector.net.
I’ve seen some very interesting setups in my time living on the road. Some folks seem to have a misguided understanding of which direction to tilt their panels. More than once, I’ve seen panels tilted in directions other than South. So to reduce the confusion, here are a few common misconceptions that I’ve witnessed on the road:
Misconception 1: If I tilt my panels to the West, I’ll get the most amount of power before night time, which is when I need it most.
I can see why some might think this way, but this is misguided because tilting to the West could cut your power generation by as much as 50%. If you run out of power in the night, but have the right sized solar array, you likely have a storage capacity issue and not a power generation issue. Your solar system is only as good as the quality and type of batteries you use to store the energy that is produced. You should ALWAYS tilt your panels towards the Equator (South in Northern hemisphere and North in Southern hemisphere) to maximize the amount of power that is produced.
Misconception 2: Tilting in any direction is better than not tilting at all.
Similar to the first misconception, I’ve seen several folks on the road who seem happy to tilt in any direction at all (E, W, and even N). Again, tilting in any direction except towards the equator will limit your power production. If you can’t always orient one side of your vehicle towards the South, then go with a 4 Way Tilting system like the one here, so that no matter where you park you can always angle your panels towards the South. If you can’t get within 20° of direct Southern tilt, then leave your panels flat because tilting them will defeat the purpose.
Misconception 3: It’s the same price to add an extra panel as it is to tilt.
This is something I’ve heard time and time again from folks who think that tilting is unnecessary. Yes, it may be comparable in price to simply buy an extra panel, but there are additional costs that go along with adding panels. If you up your solar array, you will also need to up your charge controller and probably your battery bank and inverter as well. A self-contained solar system should be balanced with everything sized appropriately. If you go adding a bunch of extra panels without sizing the rest of your system appropriately, you could end up overloading your charge controller, generating power that your batteries can’t absorb, or not being able to use all of the power that you do generate and store. If you do upsize the rest of your system this will add weight and unforeseen cost.
I’ve seen one family with a flat mounted 2000W system on top of their class A to meet their winter power demands. The result was that they had to spend an additional $5,000 on the rest of the system to support that huge solar array. Ironically, if they would have simply implemented a 4 Way Tilt system, they could have gotten away with a much smaller system and still met all of their power demands.
One of the first things you’ll learn as a long-term boondock camper is that versatility is everything. You want to have as many tools in your toolbox as possible to keep your systems happy and operational. It is not an easy life living on the road, issues will always arise and there will always be things to fix or tweak. Don’t let your solar system be one of them, plan for the unexpected and go with a well-designed 4 Way Tilting system. You’ll be happy you did!