solar basics

Many RVers look to solar power if they do not already have it installed on their rigs. Solar panels are a popular upgrade particularly for those who enjoy remote camping, boondocking without hookups. RV solar panels can help you run the features and fixtures that keep you living in comfort no matter where you are. And there is no noise, smell, and expense of running your propane generator. All you need is the sun and some money to invest in the perfect system.

As the popularity of solar power grows, there are questions arising about how to implement an RV solar system to generate power. How do RV solar panels work in the first place, and which are the best kinds to get for an RV? How do you hook them up? This post takes you through the basics of RV solar power to remove confusion, offer advice, and get you powered up for your next adventure.

Are RV Solar Panels Worth It?

Many campers are aware that RV solar panels are an option but they are cautious mostly because solar panels and batteries can be expensive. So this may leave you wondering if they’re worth it in the first place. To answer this, we start at the beginning: what, exactly, are RV solar panels, and how are they used?

Metal Carport For RV

RV solar panels are devices that convert sunlight into power. The sunlight hits the solar panels, creating an electric current which then feeds into a charge controller. This controls how much current goes through the battery. The batteries produce DC power, and an inverter changes this into AC power, which will run your appliances and other items such as a laptop.

The top reasons people may consider adding solar panels or look for an RV to purchase that already has them installed are:

  • To charge your “house” batteries: Solar power provides a slow, steady charge to your batteries, which is actually the way batteries are made to be charged to maximize the life of the battery.
  • To provide electrical power: Whether or not you are in remote locations, wanting to explore breathtaking views further off the road, or as back-up power for emergencies.
  • While RV solar panels are certainly not necessary, they do have a lot of benefits. If you’re hoping to really go off-grid, live more greenly or get off the radar, then installing RV solar panels will certainly be a benefit.

Solar panels can also help extend your battery life, cut down on generator use, and even save money in the long run on propane. Here are some of the benefits of adding a solar-powered system to your RV:

  • It’s a cost-effective means of power.
    It is a fairly inexhaustible resource, even during the winter months, and on cloudy days you will still see some sunlight.
  • It’s clean, quiet, and it is good for our planet, not burning fuel, therefore does not put off waste or smells.
  • RV solar systems are virtually maintenance-free. There are no moving parts to break, and once systems are set up, they can last for decades when well cared for. Plus there are practically no recurring costs. Even if in the future you decide you want to expand your solar panel system, to produce more power. It can easily be done without a whole revamp of your system.
  • They extend the life of your battery. Most RV batteries will last anywhere from two to three years, and they are expensive. With solar power, you can expect that to increase from 50% to 75% longer.
    RV solar panels allow you the freedom to enjoy living in natural settings with breathtakingly beautiful views.

How Many Solar Panels Do I Need to Run an RV?

Once you have decided to go solar, it is time to focus on the details. How many solar panels does it take to run an RV’s electricity? The answer will depend on the size of your RV and how much electric power you’re trying to generate.

A modest travel trailer that draws 30 amps and doesn’t have that many appliances is not going to need as many solar panels as, say, a 40-foot diesel pusher.

It is important to understand that solar power may not be enough to generate the kind of power you need to, say, run your HVAC system. That being said, RV solar panels appeal primarily to boondockers and off-grid RV campers, who are likely to steer their rigs to a place where the weather doesn’t necessitate any internal temperature control!

RV solar also differs from at-home solar setups in that you can’t sell excess power back to the electric company. All your solar panels are doing is charging your battery. Thus, having the smallest amount of solar wattage possible to get the job done is preferable, as the panels are both costly and heavy. The number of solar panels you need on your RV roof will also depend on how heavily you use the electricity you’re generating.

In general, most RVers travel with between one and three 100-watt solar panels, which can generate approximately 6 amps per peak-sun-hour on average, or around 30 amp-hours daily. There are online calculators to use to help determine your average power use. Once you know this, you can decide how much power you need and which panels to get.

How Much Solar Power Do You Need?

Calculate how much energy you use in a day. Your total energy consumption will be all the power used by your electrical goods, plus a small amount which is used up by things you can’t see such as energy lost within the wires. The energy consumption of DC electrical equipment is rated in amp-hours, a measure of how many amps they will use in a single hour. The capacity of your battery is also measured in amp-hours (Ah), with most RV batteries around 70-90Ah. A battery rated 72Ah will be able to power a 1Ah light for 72 hours, or a 12Ah water pump for 6 hours.

AC electrical usage is usually measured in watt-hours and the watt-hour ratings can usually be seen on the plug casings. Amps are just watts divided by voltage; in a 12V RV system, you can divide the watt-hour rating of your equipment by 12 to see how many amp-hours it will draw down from the battery. To calculate the total electricity you use in one day, multiply the amp-hours of each piece of equipment by the number of hours you use it.

For example, if you use a 5Ah phone charger for 2 hours a day, the total energy usage will be 5Ah x 2 = 10Ah. Add up the amp-hours for all your equipment to estimate your total daily power usage, rounding your answer up to cover any power loss within the system.

If you aren’t sure about the power consumption of all your equipment, there are helpful lists of standard amp-hour ratings online as well as online worksheets that will help you to calculate your usage. As a rough rule, one solar panel and one or two batteries will enable you to live a frugal lifestyle, running only the basics. If you want to use a TV, computer, and microwave, you’ll need two panels and up to four batteries.

Here are three rough breakdowns of the power used by three very different RV lifestyles to help you evaluate your RV living and what power you need to achieve that.

Ascetic: This involves running a single overhead light for 2 hours a day, plus a water pump for 20 minutes. There is no use of the vent fan, and no heating. You can charge a phone for 2 hours a day but no other electronic entertainment. About 2Ah will be eaten up by miscellaneous items like a carbon monoxide detector and clock and some power will be lost in the system. This eco-friendly lifestyle will take about 10-15Ah/day.

Cautious: You will be running lights for a combined total of 6 hours and using the water pump for 40 minutes, and the vent fan for 5 hours every day. There can be up to 2 hours watching a 12-inch DC TV or 4 hours using a stereo along with charging a laptop for 2 hours a day and a phone for the same amount of time. This frugal lifestyle will require around 50-60Ah per day.

Like home: You increase comfort levels by running lights for a combined total of 10 hours and the water pump for an hour. You are watching a large TV for 4 hours a day and using the microwave for 30 minutes, as well as using your laptop plugged in for 4 hours and the vent fan for 8 hours a day. A propane-powered refrigerator and gas stove for cooking will also be included. This moderately lavish lifestyle will take 120-150Ah per day.

In general, RV batteries can store 70-90Ah. You will need battery capacity to store at least twice as many amp-hours as you use in a day. Ideally and where possible, aim for 3-4 times more than you need. RV batteries can be damaged by running them down below 50% charge, so you will want to keep some backup power for overcast days as well as times when you use more power than usual.

RV Solar Panel Installation

RV solar systems are simple to maintain once installed. But, getting it set up isn’t as simple. There is more to it than slapping some panels on top of your RV and calling it good. There are other essential parts involved needed to convert the solar-generated power into usable electricity, such as a controller and an inverter.

The RV solar panels route to a solar charge controller, which sends the energy your panels have created to the on-board battery system. It’s called a “controller” because it modifies how much energy reaches the battery, so as not to overcharge them. Then, the inverter is used to convert the energy from DC to AC power, so you’ll be able to utilize all your onboard appliances and gadgets.

Here’s an overview of the basic parts you need to install and run an RV solar setup:

  • Panels: Along with the information above, they do come in various sizes, and you can even purchase additional ones, and add more later, without a whole system overhaul.
  • Charge controller: This will regulate the flow of electricity to your batteries to prevent them from getting overcharged.
  • Battery monitor: This is great to keep track of your battery levels because you want to know exactly how many more amp hours you have.
  • Inverter: To convert the DC power from the panels into AC power, which is used to power things like your coffee maker, phone chargers, laptops, and TV.
  • Wire harness: To carry the charge from the panels to the batteries.

What is the Best Solar Panel for RVs?

When it comes to getting an RV solar system, you will notice there are a variety of different types out there, each having its own unique drawbacks and benefits. RV solar panels also come in both rigid and flexible versions, which you also want to consider before purchasing. In the RV world, there are currently three types of solar panels on the market.

  • Mono-Crystalline: made from a single crystal and individual cells are thin wafers of silicon crystal.
  • Poly-Crystalline: contain several smaller crystals.
  • Amorphous: thin-film panels with cells made of a thin layer of silicon, attached to a backing material.

The roof of your RV is like prime real estate, so you need to invest wisely. When deciding what may be the best solar panels for your RV, you must consider size, as well as efficiency. Amorphous systems are the most affordable and have a high-efficiency rate, they are twice the size of poly-crystalline and mono-crystalline. Mono-crystalline panels are also highly efficient and are said to produce more power in low-light conditions than poly-crystalline or amorphous. Poly-crystalline, however, is the most popular, taking up half the space of the amorphous systems, and producing just slightly less power than mono-crystalline panels. Depending on your needs, one of these systems will work best for you.

Flexible or Fixed?

Flexible solar panels, also known as thin-film panels, are the newest in the field of solar energy. These types of solar cells are extremely lightweight, and you can install more in a larger space without adding too much weight. While they are still made of silicon, they require less to produce and are capable of generating just as much energy as the traditional panels. Flexible panels can also be installed directly on your RV roof, which makes them more streamlined and pleasing to the eye.

There are also disadvantages to flexible panels to consider. It is not safe to walk on these panels, even if the company advertises that you can. They can develop very small cracks under pressure, and that, in turn, will reduce their power output, and shorten their lifespan. Most of these will come with only a 10-year warranty, which is only a third of their counterparts.

You also need to consider heat buildup. The more space you have between your panels and the roof, the cooler they will stay and the more power you will generate. As flexible panels get hotter, all that heat buildup goes right into the interior of the roof they lay on. While this is great for colder winter months, it is not pleasant in the summer. Installation of flexible panels also requires you to glue them to your roof, and removal is not easy later on. While, individually, these disadvantages would not be a deal-breaker, they are worth looking into for your individual needs.

Rigid RV solar panels are hard and firmly fixed. They are constructed using glass panes within an aluminum frame. The most obvious, of the advantages, is durability. They can withstand the harsh conditions associated with travel and are by far the best choice for the long-term. For those with the environment in the back of their minds, silicon is more environmentally-friendly, when it comes time for disposal or recycling.

Another benefit includes a high resistance to heat. The more space you have, between the panels and your RV, the less heat it will produce. These panels can be mounted with a space between them and your RV roof, and they usually have a lower installation cost. They can be mounted to hinge and tilt. So you are still able to take care of normal roof maintenance, without worrying about stepping on them.

Rigid panels do weigh more than flexible ones, thus adding more weight to your rig. Rigid panels also stick up above your roof somewhat and can be an eye-sore. They can also be harder to place in-between AC units, and other things on your RV roof unless you build a rack for them lifting them up above your vents and antennas. While they are regulated to withstand the high winds, hail, and even extreme temperatures of RV life, they are made of glass, which is breakable.

You can also invest in portable solar kits. Portable solar kits allow you to move your solar panels, to get the most sunlight, even when your RV is under the trees. They are great for smaller campers and RV and are a great addition to your larger permanent system. These portable kits come with cables, to allow you to move the portable panels around with ease.

How Much Does it Cost to Install RV Solar Panels?

We all know RV solar is expensive, but how expensive is it, exactly? The total cost of your RV solar system will depend on your needs and your specific RV solar setup. The good news is that it is very customizable because what may work for you, may not work for other RVers. Prices for systems generally start at a few hundred dollars and go up from there. As solar power gets more popular, as has been happening, you will see prices begin to drop.

Hooking Up RV Solar Panels to RV Batteries

The specifics for setting up your RV solar panels will depend on the make and model of your rig as well as the type of panels, controller, and inverter you have. You should always check with your owner’s manual or a trusted RV solar professional, to make sure you get proper step-by-step installation instructions. Keep in mind that setup needs vary and you don’t want to risk overpowering your batteries or even shocking yourself. If you have any doubts about how to install your RV solar panels, my friend DAN can help you

Installing solar on RV roofRV Solar Panel Pros and Cons

So, are they worth it? While they can be costly to set up, RV solar systems do generate free power for the lifetime of your system, and they are fairly low-maintenance after the initial installation. As long as you have enough light to cast a shadow on the ground, your panels are capable of producing power. You have the freedom to move around and take advantage of boondocking spots without annoying smells and sounds, getting you right back to nature.

Keeping some of these basic RV solar panel tips in mind can help you extend the lifespan of your system so you get the most return on your investment. Keep your RV panels clean to keep them efficient as even the least bit of dust or debris will lower your power. Make it a routine practice to check on this.

It is also important to know that some companies will not warranty panels that are installed on an RV. Look for dealers that specialize in either solar panels for RV roofs and/or systems that are made especially for RV’s and campers. Overall, solar panels are a great addition to your RV and a good investment. You get to extend your camping experience, they are great for our environment and will save you some money.

We are here to help you find which options you have for your setup, or if you are a “Do-It-Yourself-er,” we can guide you to the research for products that best suit your needs. You can also consider renting an RV with solar power capability to get a real feel for how they work. Once you commit, you will not regret it. Camping just got better!