Take charge with everything you need to know about solar power.


If you're putting together an RV solar power system, you may be wondering what you can power with it. Low-power devices are easy to accommodate, but what about high-wattage appliances like an off-grid air conditioner? 

**A solar power system can power an RV AC unit.** With enough solar panels, you can power just about any appliance. The bigger concern is *how many* solar panels are required to power an AC unit. Roof space and budget will limit the number of solar panels that you are able to drive around with.

In this article, we will explore the amount of power that an RV AC unit consumes, which will help us determine how many solar panels are needed to keep your RV cool. 

![a man installing an ac unit in a solar powered rv](images/can-solar-panels-power-rv-ac/man-installing-rv-air-conditioner.jpg)

## How Much Power Does an RV AC Unit Use?

A typical 13,500 BTU RV air conditioning unit may draw 2750 watts at startup and 1,250 [watts while running](https://www.ramsond.com/wattage-chart/). If the AC unit is operating for 3 hours per day, it will consume 3,750 watt-hours (Wh) per day, or 3.75 kWh (energy = power x time, so Wh = Watts x Hours). 

A camper van may be able to get away with a smaller AC unit, such as a 7,000 BTU RV air conditioner rated for 600 running watts. This unit will consume 1,800 Wh if it runs for 3 hours per day. 

## How Many Solar Panels to Run My RV AC Unit? 

In order to calculate the number of solar panels we need to operate an off-grid AC unit, we have to determine the amount of power we want to supply. If we plan to run a 1,250W AC unit for 3 hours per day, then we need to produce at least 3,750 Wh each day. 

Consider this formula for determining the wattage of a solar array:

	Array Wattage = Desired Energy Production ÷ Sun Hours

If you are using an AC Unit, we can assume that you will be receiving summer levels of peak sun: at least 4 hours per day, depending on your location. In the winter, peak sun hours may fall to about 2 per day (which makes it difficult to power an electric RV heating system). 

If we fill in the information that we already have, our equation now looks like this: 

	Array Wattage = 3,750 Wh ÷ 4 Sun Hours = 937.5 watts
	
So, in order to power this AC unit for 3 hours per day while receiving 4 peak sun hours, we would need a solar array with a total wattage of at least 937.5 watts. **An array of ten 100W solar panels (or three 400W panels) is needed to power this RV AC unit in optimal summer conditions**. 

Note that you will need additional panels to power the other appliances and devices in your RV, such as phones, lights, and laptops. View our [solar array sizing guide](https://optivolt.com/blog/how-many-solar-panels-do-i-need) for more details on calculating the number of panels you need for an entire RV solar power system.

![a man installing an ac unit in a solar powered rv](images/can-solar-panels-power-rv-ac/solar-powererd-rv-air-cooling-unit.jpg)

## Solar Components Required to Run an RV Air Conditioner

An RV requires more than just solar panels to supply power to an AC unit. The power produced by solar panels needs to be stored for later use, safely transferred throughout the system, and converted into usable energy. Every [RV solar power system](https://optivolt.com/blog/rv-solar-panels-guide) is different, but most will include at least these components:

- **Battery Bank**: Once the sun goes down, your panels stop producing power. A battery bank stores solar energy for later use, allowing you to power devices and appliances even when your solar panels are not producing power. 
- **Charge Controller**: The [solar charge controller](https://optivolt.com/blog/solar-charge-controllers-guide) is wired in between the solar panels and the battery bank. This device regulates the battery charging process, providing safety and optimization. Without it, your solar panels may overcharge the battery bank. Most charge controllers can also power basic DC loads like lighting.
- **Inverter**: The power generated by solar panels is direct current (DC). Most RV air conditioners run on alternating current (AC) power. An inverter converts DC power into AC power that can be used by RV AC units and other appliances. 
- **Wiring and Connectors**: Everything needs to be joined together with the proper wire gauges and connectors to ensure a safe system.

If you are not interested in purchasing and connecting your own solar components, other options are available. Portable power stations (also referred to as solar generators) are a popular alternative. They are a convenient, all-in-one solution that packs all of the solar components into one package with no assembly required. They do have a higher upfront cost, so you need to decide if the convenience is worth the price. 

## Do I Need an Inverter? 

The typical off-grid air conditioner operates on 120V AC power. In order to run a 120V AC appliance using solar power, you need an inverter to convert the power produced by solar panels from DC to AC. 

If you happen to have a 12V DC air conditioning unit, then you won't necessarily need an inverter. However, this is a rare case, and an inverter may still be required to power other devices and appliances in your RV.

Inverters have two primary wattage ratings: continuous and peak surge. If a 13,500 BTU RV air conditioning unit is rated for 2750 surge watts and 1250 running watts, then you need an inverter rated for at least these values (while also considering the other appliances that you need to power). In this situation, you might utilize an inverter with ratings of 2000W continuous and 4000W peak surge. 

## Is Powering an RV AC Unit With Solar Worth It? 

In general, powering an RV AC unit is not worth it. The amount of power required to run an RV AC unit can be difficult to harvest using just solar power. This is due to roof space, budget, and other constraints. 

Instead of trying to power an off-grid air conditioner, RV owners that want to stick exclusively with solar power should try and follow the seasons: head to cooler weather in the summer, and move south for a warmer winter. That way, you can use your harvested solar power for other appliances and devices.

If you still want to go for it, use high-efficiency solar panels to help you generate more power. Partial shading — a common occurrence with RV solar panels — can cause severe drops in panel output, even when just a small portion is blocked out. 

Optivolt produces one-of-a-kind [shade tolerant solar panels](https://optivolt.com/optivolt100). The integrated power electronics technology maximizes efficiency in shaded conditions. 





RV solar power systems can certainly power basic appliances like lights and smartphones, but can they power a high-wattage RV air conditioner? Let’s find out.

Can Solar Panels Power an RV Air Conditioner?


Solar panels have quickly become the future of energy production. Solar arrays can make use of ineffective space like a roof and turn it into an energy generator. But when a tree, building, or other obstruction shades just one portion of a panel, the entire panel's output can be rendered useless. 

Most solar panels are ineffective in the shade, but a new innovation by Optivolt is changing this fact. In order to determine whether or not solar panels work in the shade, we first need to take a look at how this technology functions in the first place. 

## How Solar Panels Work

In order to determine if solar panels work in shade, we first need to understand how they function. As we know, photovoltaic (PV) panels convert sunlight into usable electricity. Each panel is composed of many solar cells. Sunlight causes the electrons in a cell to move from low-energy to high-energy states, which generates voltage and electric current. This process is known as the photovoltaic effect. 

The solar cells in a panel are typically connected in series to achieve a high voltage. In a series circuit the voltage of each cell adds up but the current is the same throughout all of the connected components. When a cell is shaded, fewer electrons become excited and less current is generated. This leads to the rest of the connected cells being limited to the reduced output of the one shaded cell. 

This phenomenon unfortunately works on a larger scale as well. When one panel in an array has reduced output due to shading, the rest of the panels are also affected (assuming that they are connected in series). These bottleneck effects explain why partial shading can have such a drastic effect on solar panel output. 

## Will Solar Panels Work in the Shade?

Yes, solar panels will still work under some shade. However, their output will decrease dramatically. Most solar panels utilize the same basic technology outlined above, in which the shading of even one cell will reduce the entire panel's output. If 10% of the panel is shaded, you don't just lose 10% of the power output — a panel (or an entire array of panels) can be rendered practically ineffective if just a few cells become blocked. 

## Best Solar Panels for Shaded Areas

Shade-tolerant solar panels are the best solar panels for shaded areas. They are a new advancement in solar technology that gather more energy in real-world, shaded conditions. Until now, nobody had been able to solve this problem at a price point that made sense for consumers. Now, Optivolt is making shade-tolerant solar panels available for both residential and RV solar systems. 

![optivolt shade-tolerant solar panels in campground](images/do-solar-panels-work-in-shade/optivolt-campground-rv-panels-roof.jpeg)

[Optivolt’s shade-tolerant solar panels](https://optivolt.com/optivolt100) improve upon high-efficiency monocrystalline panels by embedding Pulse power electronics technology into each panel. In a traditional panel, a shadow creates a wall that blocks the flow of power through the entire panel, drastically dropping power output. Optivolt’s Pulse technology cleverly re-routes the power flow around the shadow(s) and back out, enabling up to 60X more power delivered under shade.


These solar modules are a great option for solar-powered RVs and camper vans, as these mobile setups are always in and out of shaded areas. With the limited space of an RV roof, maximizing the array's output is especially important. Flexible panels have been used in the past to try and increase solar panel real estate, but the sun often reaches these curved modules in uneven ways which leads to lower output. 

For example, a small camper van or RV may have three 100W solar panels attached to their roof. In optimal summer conditions, this 300W array may generate around 1.2 kWh of power per day. 

When just one cell becomes shaded by 40%, that covers just 0.37% of total solar area, yet the entire output of the array could decrease by 40% (depending on how the panels are wired together). If this shading was consistent throughout the day, the potential output would decrease to only 720 kWh. Plus, the shaded cell will generate heat and degrade at a faster rate. 

When this same scenario occurs with [shade-tolerant solar panels](https://optivolt.com/optivolt100), the results are much different. The panel's shade-affected zone is the only section that experiences reduced production — the rest of the cells are able to contribute their full power. This means that the overall power output only drops by a small portion. 

## Avoiding Shade with RV Solar Systems

Summer RV trips usually involve searching out a shady spot in the forest — unfortunately, this means less sunlight for your RV solar panels. This could pose a problem if you use a lot of energy, but you can take a few steps to avoid running out of charge. 

It's important to remember that the summer provides more sun hours than winter. So even if your panels are partially shaded by towering ponderosas for a few hours, you should still be able to capture an adequate amount of energy while the sun is overhead. 

That being said, installing shade-tolerant solar panels can help you eke out every last bit of sunlight. When foliage shades a fraction of your array, it will provide much more power than other RV solar systems. This can be the difference-maker in being able to support high-powered appliances like refrigerators, water heaters, and microwaves. 

![solar powered rv driving and casting a shadow](images/do-solar-panels-work-in-shade/solar-powered-rv-driving-daytime.jpg)

## Making the Most of Partial Shade

You can take various steps and precautions to reduce or eliminate the negative effects of shaded solar panels. 

- **Avoid Regular Shading**: If you have a choice of where to install your panels, then avoid future issues by placing them in a sunny area. Before installing your array, monitor the potential site and watch for potential shading issues. Does a chimney, building, or tree shade the area for a significant portion of the day? If so, try to identify an alternative location for your solar panels. 

- **Install Shade-Tolerant Solar Panels**: Optivolt has innovated new technologies to reduce the effect that shade has on a solar array. Shade-tolerant solar panels are finally bringing new ideas to a stagnant industry. With the advent of their Pulse technology, the [Optivolt](https://optivolt.com) 100W solar panels are able to harness energy in the shade with high efficiency. This technology is essential for RV solar systems that will inevitably end up in the shade.

- **Use MPPT Charge Controllers**: Maximum Power Point Tracking (MPPT) is a technology used in solar charge controllers and panels to maximize electricity generation. This technology continuously tracks and adjusts the various power characteristics to operate the panel at its maximum power point (MPP), which is calculated as a product of voltage and current. MPPT doesn’t solve the shading problem like shade-tolerant panels do, but they will ensure that the system isn’t wasting power by operating the panel at a non-ideal voltage. 

- **Move Your Panels**: A solar-powered campervan or RV allows for the luxury of moving panels throughout the day. An attentive camper can re-park the vehicle over the course of an afternoon to maximize the gathered sunlight. Solar arrays mounted on tiltable brackets — either automatic or manual — allow the user to adjust the angle of the panels. This could be the difference between receiving full or partial sun. 

- **Be Energy Conscious**: If you are experiencing a bout of cloudy weather or other shading issues, you can always attempt to reduce your energy usage until you are generating full power again. Turn lights off when they are not in use, only open the refrigerator when necessary, and use the heater only when necessary.

## Conclusion

Partial shading can have drastic effects on the output of your array due to the manner in which most traditional solar panels are constructed. Since they are a series circuit, the output of the entire panel or string is brought down to the level of the weakest cells. 

Optivolt has worked to solve this issue and create the best solar panels for shaded areas. Optivolt has been engineering new technologies for over five years to great success. Their unrivaled Pulse technology is now available to use in the form of a 100W solar panel, delivering up to 60x more power in shaded conditions vs traditional panels.

What steps will you take to limit the effects of shading on your solar panels? 



‘Traditional solar panels are ineffective in the shade. Learn how shade-tolerant solar panels are able to efficiently generate power in adverse conditions.’

Do Solar Panels Work in the Shade?


Are you worried about how snow might affect your solar panels? Unless you live in the ever-sunny Southwest, your solar panels will inevitably have to endure winter storms each year.  

**Snow is not inherently bad for your solar panels, but it can pose a few issues.** If snow accumulates on a panel, it will block out the precious sunlight that allows your solar array to produce electricity. And if heavy snow is left to sit on your solar array, it can have negative effects on the mounting hardware. 

Let's explore how snow can affect solar panels in further detail. 

## Solar Panels in Snow: Reduced Efficiency

When snow accumulates and blocks out just a small portion of a panel, the rest of the panel's output decreases dramatically. Once a few cells are obstructed, the panel's output drops to nearly zero. The same thing happens when panels are partially obstructed by trees, buildings, and other structures — most [solar panels do not work in the shade](https://optivolt.com/blog/do-solar-panels-work-in-shade). 

Because of this fact, constant vigilance is required in the winter to keep your panels free of snow and producing as much power as possible. You will need to hop on the roof and clear your panels whenever you receive more than a dusting. 

To ensure that an off-grid solar array produces enough power in the winter, homeowners can utilize [shade-tolerant solar panels](https://optivolt.com/optivolt100). These modules are not limited by the shading of one cell like traditional panels. Heavy snow will still need to be cleared off, but they will perform well in light snow and other partially-shaded situations. 

![partially-covered solar panels from snow](images/how-does-snow-affect-solar-panels/solar-panels-partial-snow.jpg)

Lower efficiency is less of a concern for grid-tied solar power. If power generation is reduced, these systems can utilize power from the electric grid. When an off-grid system experiences heavy snowstorms, they run the risk of running out of power altogether.

In addition, residential systems usually produce more power in the summer than the household can consume. Utility companies will compensate homeowners for this extra electricity in most states under net-metering laws. This profit can then be applied towards your electricity bill in the winter months, when snow and low sun hours reduce power generation. 

## Heavy Snow on Solar Panels

When you receive a heavy snow, power generation becomes a secondary issue (as long as you are grid-tied or your solar batteries are charged up). Instead, the weight of the snow could pose a problem for your panels' support structures. 

Heavy snow can put stress on the solar panel support structures due to the way they are constructed and mounted. For extended snowstorms, you will need to clear the snow as soon as possible to prevent immediate or future damage to your panels. Heavy snow accumulation for a long period of time will affect the long-term integrity of your mounting system. 

## Fixing the Problem

There are a few steps you can take to minimize the effect that snow has on your solar power system:

- **Removing Snow from Solar Panels**: In general, solar panels require minimal maintenance. But if your area receives heavy snow, you will need to stay on top of snow removal to keep your system functioning at maximum efficiency. Keep safety in mind when working on your roof, and feel free to hire a professional if necessary. Your safety is more important than your solar panels. 
- **Tilt Angle**: If you adjust your panels to a higher tilt angle in the winter, you will receive two benefits. First, snow will slide off easier. Plus, your panels will be facing the sun’s lower path through the winter sky. Consult our [tilt angle and orientation guide](https://optivolt.com/blog/best-direction-for-solar-panels) for more details. 
- **Shade-Tolerant Solar Panels**: In light storms, only part of some panels will become blocked by snow. However, this can have a large impact on power generation. When one portion of a panel becomes obstructed, the rest of the panel’s output will suffer. [Shade-tolerant solar panels]((https://optivolt.com/optivolt100) can mitigate this issue — these panels perform better than traditional solar panels when part of a panel is blocked out.

![snow covering a home’s solar array](images/how-does-snow-affect-solar-panels/roof-solar-panels-covered-in-snow.jpg)

## Can Snow Benefit Solar Panels? 

A light dusting of snow on solar panels can provide at least one benefit. [Snow has anti-soiling properties](https://www.energy.gov/eere/articles/let-it-snow-how-solar-panels-can-thrive-winter-weather) that cause it to bond with dirt. When the snow melts, it will take dust and dirt with it, exposing your panels to more sunlight (the same effect can be observed on your car windshield). This allows your panels to work at a higher efficiency as long as they stay free of snow. In addition, very cold weather significantly increases the conversion efficiency of the solar cells by reducing cell temperature, giving the solar panel a slight powerup during lower light availability all winter.

## Conclusion

Heavy snow brings a few issues to your solar array. The snow can block out sunlight, reducing the efficiency of your panels. Plus, the weight of heavy snow can damage the mounting hardware that supports your solar panels.

In order to maximize energy production in snowy conditions, try utilizing solar panels that work in partial-shade. [Optivolt](https://optivolt.com) is leading the research and production of shade-tolerant solar panels. Their Pulse technology equips solar modules with the ability to perform at maximum efficiency — even when part of the panel is obstructed by snow.




Unless you live in the sunny Southwest, your solar power system will experience snowfall each winter. Learn about the effects that snow has on solar panels.

How Does Snow Affect Solar Panels?


Are you ready to embrace solar power and free yourself from the constraints of loud generators and shore power? Not sure where to start? The world of solar power can be intimidating for first timers, but an RV solar system comes together easily for most people. 

A solar-powered RV allows you to go out on bigger adventures and deeper into the wilderness. Without having to rely on campgrounds for shore power, you'll be able to go boondocking for weeks on end. 

There are a few essential things to know before purchasing your RV solar panels. Preparation, planning, and learning are all essential parts of the process.  

## What Are RV Solar Panels? 

RV solar panels are photovoltaic (PV) modules that convert sunlight into electricity that can be used in a recreational vehicle. The same panels that are used on homes, camper vans, and other solar power systems can be used on an RV. 

Most RV solar panels are rated between 100 and 400 watts. The higher the wattage rating, the more power that the panels will produce. Under optimal conditions, a 100W RV solar panel can be expected to produce around 400 Wh of energy per day (energy = power x time, so Wh = Watts x Hours) Correspondingly, a 400W panel may produce around 1600 Wh (1.6 kWh) per day. When winter comes, expect a lower output — peak sun hours can drop as much as 50% in December and January.

![solar powered rv driving in Iceland](images/rv-solar-panels-guide/iceland-rv-solar-powered-mist.jpg)

## How Does an RV Solar System Work? 

An RV solar system works by generating electricity from sunlight, and then delivering the energy to your appliances and devices. This is accomplished in a few steps.

First, the RV solar panels receive energy from the sun, which is converted into direct current (DC) power. This power is sent to your RV batteries for storage. Then, the charge from the batteries is distributed through the RV, powering lights, heating units, and other appliances. An inverter is connected to the battery to provide convenient 110-120V AC wall outlets you can plug anything into, from an iPhone to a minifridge.

## The Different Types of Solar Panels for RVs

There are a few different types of solar panels commonly used on RVs: monocrystalline, polycrystalline, shade-tolerant, and flexible. 

### Monocrystalline Solar Panels

Monocrystalline solar panels have cells which are constructed from a single crystal structure of silicon. They are characterized by their high efficiency, uniform dark cell coloring, and sleek appearance. They generally cost more than polycrystalline panels, but they provide more energy generation in return. 

Monocrystalline panels are typically rigid solar panels, meaning they are built into a metal frame and are not flexible. Sometimes they are laminated with flexible materials such as PET and ETFE, without a metal frame to make semi-flexible panels for marine and RV use.

These types of panels are plagued by their inability to produce much (or any) energy in partially-shaded conditions. When one cell becomes blocked by foliage, snow, buildings, or other obstructions, then the rest of the panel's output drops as well. This is due to the way that the individual solar cells are wired together. 

### Polycrystalline Solar Panels

Polycrystalline solar panels use solar cells composed of multiple silicon crystals. They are lower in cost than monocrystalline panels, but they have a reduced efficiency. Polycrystalline panels are known for their uneven, patchwork blue coloring. Like their monocrystalline counterparts, polycrystalline panels are rigid solar panels and must be mounted on flat surfaces. 

With the limited space of an RV roof, monocrystalline panels are usually preferred due to their increased power generation. 

### Shade-Tolerant Solar Panels

[Optivolt’s shade-tolerant solar panels](https://optivolt.com/optivolt100) improve upon high-efficiency monocrystalline panels by embedding Pulse™ power electronics technology into each panel. In a traditional panel, a shadow creates a wall that blocks the flow of power through the entire panel, drastically dropping power output. Optivolt’s Pulse technology cleverly re-routes the power flow around the shadow(s) and back out, enabling up to 60X more power delivered under shade. Optivolt panels generate electricity at high efficiency even when one portion is blocked (unlike other monocrystalline and polycrystalline panels). 

![optivolt solar panels mounted on rv](images/rv-solar-panels-guide/diy-panels-rv-optivolt.jpeg)

This type of solar panel can help ensure that RV batteries stay topped up even in adverse conditions. Power generation will be increased during cloudy days or shady forest afternoons — both common occurrences for RVers. 

### Flexible Solar Panels

True flexible solar panels — also known as thin-film or amorphous — are thin, bendable panels known for their ability to be mounted on curved and irregular surfaces. Semi flexible (often known as flexible too) solar panels are Monocrystalline panels laminated with flexible plastics and without a frame. RV owners can install flexible or semi flexible solar panels in otherwise unmountable locations, such as the curves found on a vehicle. 

True flexible panels are usually constructed with cells made of Copper Indium Gallium Selenide (CIGS) or amorphous thin silicon. These cells perform at much lower efficiencies than rigid cells but are extremely lightweight. This means thin-film panels need much more area to make the same amount of power as panels built with rigid silicon cells. Semi-flexible “flex” panels made with rigid silicon but layered with flexible materials have similar efficiency to their rigid counterparts.  

## How Many Solar Panels Do I Need for My RV? 

The [number of solar panels](https://optivolt.com/blog/how-many-solar-panels-do-i-need)) required for an RV solar system depends on a few factors, including: 

- **Estimated Energy Usage**
- **Sun Exposure**
- **Solar Panel Model**

Let's explore these factors in further detail. 

### Calculate Your Energy Usage

Let's explore a quick example in which an RV is equipped with the following devices and appliances. To start, we need to gather the wattage rating for each appliance: 

- 4 x **LED Lights — 52 watts** (13 watts each)
- 1 x **Small Refrigerator — 60 watts**
- 1 x **Air Conditioning Unit — 500 watts** 
- 1 x **Vent Fan — 36 watts**
- 1 x **Small TV — 90 watts**

Next, we need to estimate our daily usage of each device. Take a look at the label, manual, or online manufacturer specification for each device, taking note of typical and maximum power draw. This will allow us to calculate the watt-hours (Wh) that we can expect each device to consume. 

- LED Lights: 52 watts @ 2 hours = 104 Wh
- Small Refrigerator: 60 watts @ 24 hours = 1440 Wh
- Air Conditioning Unit: 500 watts @ 3 hours = 1500 Wh
- Vent Fan: 36 watts @ 5 hours = 180 Wh
- Small TV: 90 watts @ 2 hours = 180 Wh
- **Total Daily Usage: 3,404 Wh**

So, our daily energy usage for this example would be 3,404 Wh. Let's round up to **3,600 Wh** as an added buffer for extra energy consumption (more lights on some nights, charging smartphones and laptops, etc.) 

Keep in mind that real life conditions may alter the actual power draw of some of your appliances. For instance, some refrigerators may run at full power 24/7, while others may shut off and on at different times of the day. To be safe, install more solar power in your RV than you think you need, especially if you are not using shade tolerant solar panels. 

![interior of a solar powered camper van](images/rv-solar-panels-guide/interior-solar-powered-camper-van.jpg)

### Sun Exposure and Solar Panel Wattage

Most regions in the United States receive at least 2 sun hours per day in the dead of winter. If you're in an RV, traveling around the country, then it is best to use this low estimate for your calculations. Plus, when you visit perpetually-sunny areas like the Southwest, you won't have any trouble keeping your batteries topped up. 

In the previous section, we calculated that we would need at least 3,600 Wh of energy production per day. In this case, our RV solar panels have 2 hours each day to produce the 3,600 Wh. We can use the following simple calculation to determine the number of watts needed from our solar array:

*3,600 watt-hours ÷ 2 peak sun hours = 1800 watts*

So, in order to produce 3,600 Wh of energy on a day with 2 peak sun hours, we need a solar array of at least 1800 watts. 

### Choosing an RV Solar Panel: Wattage, Size, and Quality

By now, you should have a good idea of your estimated energy usage and the sun hours you expect to receive. Choosing your RV solar panel is the last step in determining how many total panels your system will need. 

RV solar panels come with a wattage rating between 100 and 400 watts. The 100W models are proportionally smaller and better suited for mounting in the nooks and crannies of your RV's roof. Camper vans and other smaller vehicles may not even be able fit a single 400W panel. 

**Assuming that the RV is using 100W solar panels, it would need 18 panels to produce 3,600 Wh over the course of a day that receives 2 peak sun hours.** 

Unlike most full-sized homes, an RV comes with limited roof space. Before purchasing your panels, make sure you have enough space to mount the entire array. Account for the space that other roof-top additions (AC units, vent fans, etc.) will take up. If you can't fit the full array, consider decreasing your daily energy usage. 

Purchasing high-quality solar panels can help ensure that you always generate the electricity that you expect. Shade from trees and buildings can severely decrease the output of your solar array. To counteract this effect, utilize shade-tolerant solar panels — a newer technology that increases power generation in partial-shade conditions.

## RV Solar Systems: Additional Equipment

The rest of the components are sometimes referred to as the balance of system (BOS). This term encompasses every component except for the solar panels, which includes battery banks, charge controllers, inverters, and other equipment. 

### Battery Bank 

RV solar batteries store the energy produced by a solar array. This allows you to power your devices even after the sun goes down. 

Let’s explore sizing a battery bank for an RV solar system. In the previous example, we estimated that an RV might consume 3,600 Wh per day. So, for one day of use, we need a battery bank that can supply 3,600 Wh of energy. 

![a red battery bank](images/rv-solar panels-guide/red-solar-batteries.jpg)

The depth of discharge (DOD) for a lithium RV battery should not often exceed 90%. This means that you should always have at least a 10% charge left on the battery to avoid shortening its lifespan. A lithium battery bank with a capacity of 4,000 Wh can be discharged 3,600 Wh and still hold a 10% charge of 400 Wh.

Batteries are often supplied with a watt-hour rating, making the math simple.

If your battery is rated in amp-hours, you will need to do one quick calculation to find the watt-hour capacity:

*Watt Hours = Amp-Hours × Battery Voltage*

Make sure that you check your battery and plug in the correct voltage for this calculation. Batteries for solar power systems are usually 12V, 24V, or 48V. In the following calculation, we will calculate the watt-hour capacity for a 12V lithium battery rated at 200 Ah: 

*Watt-Hours = 200 Amp-Hours × 12 volts = 2400 Wh*

So, one 12V battery rated for 200 Ah has a capacity of 2400 Wh. We would need two of these batteries to supply one day’s worth of power. 

However, what if you want to be energy autonomous for more than one day? A weekend? A week? 

### Energy Autonomy

Sometimes, bad weather will prevent your panels from producing energy. More battery capacity will allow you to draw upon stored energy for a longer period of time. Let’s say that we want to ensure energy autonomy for at least three days at a time — we can just triple the battery capacity (12,000 Wh, or 12 kWh) to provide this. 

You can increase the watt-hour capacity of your battery bank by wiring multiple batteries in either series or parallel. Please follow OEM manual and specifications for advice on how to best wire your particular batteries into a larger pack.

### Charge Controller

The [solar charge controller](https://optivolt.com/blog/solar-charge-controller-guide) is installed in between your solar panels and the batteries. This device regulates the power that flows from the solar panels into the batteries, manipulating the voltage and current to meet your battery's expectations. A charge controller provides critical safety features, such as protection against overcharging and excessive discharging. 

### Inverter

An inverter is found in most RV solar systems. This device converts the DC (direct current) power produced by the solar panels into AC (alternating current) power that can be used by household appliances. 

Solar panels produce DC power, which is then stored in your batteries. Many electrical loads can run on 12V DC power, such as RV refrigerators, AC units, fans, lights, and other devices. However, devices that are commonly used in homes usually require an AC power outlet, such as TVs and laptops. If you plan on using AC-powered devices, you need an inverter. 

### Battery Power Stations

Battery power stations are a convenient solution that combine the charge controller, battery storage, and inverter into a single integrated unit. However, this convenience typically comes at a premium compared to sourcing the individual components separately and doing the wiring. If you’re looking for the simplest and fastest way to power your RV and are not cost-sensitive, battery power stations are a great option.

### Shore Power Capabilities

Do you plan on camping at RV parks or campgrounds? If so, you may want to add shore power capabilities to your RV solar system. 

To do this, you can install an **inverter charger** into your system. This serves the same purpose as a traditional inverter (converting power from DC to AC in order to use 120V appliances) while also allowing your batteries to be charged from an external AC source. Once installed, you will be able to charge your batteries using the shore power found at most RV campgrounds. 

![aerial view of a solar powered rv](images/rv-solar-panels-guide/aerial-view-solar-rv.jpg)

## Adding Solar to RVs 

In this section, we will provide a general overview of RV solar installations. This is not intended to be an all-encompassing guide, so further research should be performed to explore the nuances of adding solar to RVs. Each component will likely come with its own instructions for proper installation. 

The main steps of installing your RV solar panels are as follows:

### 1. Mount the Panels 

Start by planning out the measurements and mounting points for your solar panels. Do your panels come with mounting brackets, or will you need to fashion your own? Make sure the panels won't be shaded by any other RV roof fixtures. 

Some mounting brackets will require you to drill into the roof of your RV, while others can be attached with a strong adhesive. Consult the instruction manual for your panels to determine the intricacies of installation. 

It can't be overstated enough: plan ahead in detail to avoid any issues during or after installation. Once you have a solid plan for attaching your panels, proceed with caution, utilizing all possible safety measures while working on the roof. To prevent the panels from generating a voltage while you are working on them, completely cover the panels with a piece of cardboard (the box your panels were shipped in should work well) or another opaque object.

Apply sealant to the mounting points to weatherproof any holes. 

### 2. Run Wires 

Next, you'll need to run wires from the panels to your charge controller and battery bank. This can be accomplished in a few ways; sending the wires through pre-existing holes is the best option. This could be a refrigerator vent, holes previously used by plumbing or power cables, or other access points. Otherwise, check the RV manual for recommendations on how to create new access points. 

Just like in the last step, you should prepare a detailed plan before proceeding with wiring. This will include a wiring diagram, so you know the lengths, gauges, and connectors that you need to have on hand. 

### 3. Connect Components to Charge Controller

Most solar charge controllers will require you to connect your battery bank to the charge controller first, although others may specify that the solar panels should come first. 

The battery bank and charge controller should be installed in close proximity to prevent the battery wire from becoming too expensive (a longer wire will need to be a heavier gauge). 

Make sure to connect the positive and negative terminals of the battery bank and solar panels to the correct ports of the charge controller. If the connections are performed correctly, the charge controller should power on. 

### 4. Additional Components 

If you have any additional components, such as an inverter, now is the time to install it. An inverter is required in order to provide power to 120V AC devices and appliances. Follow the specific component's instructions to perform a safe installation.

### 5. Start Harvesting Energy

Now it's time to park your RV in the sun and start harvesting some power! If everything is connected correctly, your charge controller should notify you that the panels are producing a voltage and that the battery is receiving a charge. 

![optivolt panels on an rv at sunrise](images/rv-solar-panels-guide/optivolt-panels-rv-sunset.jpeg)

## Is an RV Solar System Worth It? 

An RV solar system is absolutely worth investing in if you take frequent trips or live full-time in your mobile home. If you only take your RV out once or twice per year, then a full-fledged RV solar system might not be worth it. 

In order to maximize the energy production of your RV solar system, make sure to use high-efficiency solar panels. [Optivolt](https://optivolt.com) is a leading producer of innovative solar panels. Their products are embedded with Pulse™ technology, allowing them to produce power at high efficiencies in adverse conditions.

## Related Questions

### How Many Solar Panels Do I Need to Run My RV AC? 

The average RV air conditioner uses around 500 watts to cool down your mobile home. If you use the AC unit for 3 hours per day, that's 1,500 total watt-hours (Wh) of energy consumption. You would need at least four 100W solar panels to produce this energy under optimal conditions.

### What are the Best Solar Panels for RVs?

If your RV might experience shading from trees, buildings, and other structures, then shade-tolerant solar panels are the best for your RV. They are engineered for extra efficiency in partially-shaded conditions. Other solar panels can be rendered ineffective by the shading from a tree or other obstruction, but shade-tolerant solar panels do not suffer this problem. 



Are you ready to take your RV off the grid for bigger adventures? Learn about RV solar panels and the other components that make up a portable power system.

RV Solar Power: The Beginner's Guide


We’ve all had the dream: you wake up in your tiny home on a cool spring morning, flip on the lights, brew some coffee, turn on some music... all using the power of the sun. If you're taking the next step in turning this dream into a reality, it can be difficult to know where to start. But with a little planning, taking a tiny home off the grid is a very achievable goal.

In this guide, we will provide a general overview of the planning process for adding solar power to a tiny house. 

## Calculate Energy Needs

The first step of planning a solar power system is determining the amount of energy that you will be consuming. There are two methods of doing this: look at past utility bills (the simpler way) or calculate the energy usage of each appliance/device that you plan to use.

### Looking at Past Electric Bills

In 2021, the average electricity consumption in the United States was 886 kWh per month. This data is from all residential homes, so your energy usage may be lower. Most people who live in tiny homes use less electricity due to the smaller space and lower number of family members (the average household size in the U.S. is about 2.6 people). 

When looking at your own past energy usage, you should pay attention to your highest month of electricity usage. This will likely correspond with changes in air conditioning needs — regions with mild climates have correspondingly lower energy consumption on average.

Also, take into account any lifestyle changes that you plan to make when moving into a tiny home (if you don't already live in one). Even just getting rid of your television or drying machine will make a drastic impact on your energy consumption, so you may not need quite as much power as you think.

### Manual Calculation for Energy Consumption

We can also calculate energy usage manually, based on the wattage rating and expected usage of each appliance in your home. 

For example, let's estimate the energy consumption of a 10,000 BTU air conditioning unit. Most AC units of this size are rated at 1000 watts. Let's say that we will be running the unit for 4 hours each day during the hottest months. So, over the course of one 30-day month, we can expect the AC unit to run for 120 hours. 

Let's calculate the energy consumption in watt-hours (Wh). Watts multiplied by hours equals the total energy consumption in watt-hours, as follows: 

*Energy Consumption (Wh) = Wattage Rating × Hours of Use*

*1000 watts × 120 hours = 120,000 Wh (120 kWh) per month*

So, the 10,000 BTU AC unit would consume around 120 kWh in a month where it is used for 4 hours per day. 

In order to calculate your total energy usage per month, just perform this calculation for all of the appliances and devices that you plan to power in your tiny home. Then, add up their individual energy consumptions to receive a total. 

![tiny home made of metal with solar panels](images/solar-panels-for-tiny-homes/rendering-tiny-home-metal.jpg)

## How Many Solar Panels for a Tiny House? 

In order to calculate [how many solar panels](https://optivolt.com/blog/how-many-solar-panels-do-i-need) are required for a tiny house, we need to fill in the data points for this calculation: 

*Number of Solar Panels = Total Solar Wattage / Individual Panel Wattage*

And to find our **total solar wattage**, we will also need this equation: 

*Total Solar Wattage = Energy Consumption / Sun Hours*

For this example, we will make an assumption that the average tiny home owner may use **400 kWh per month** — about 50% less than the average American home. This assumption is based on the fact that a tiny home has less heating and cooling needs and is usually only occupied by one or two people. Your energy needs may differ. 

Most regions in the U.S. receive at least **60 peak sun hours** per month (or [2 hours per day](https://www.nrel.gov/gis/solar-resource-maps.html)), so we will use this for our calculations. However, many regions actually receive much more than this, especially in the summer. Make your calculations based on the data for your area. 

Now that we know our expected energy consumption, we can find the total wattage of our solar array using the equation from above: 

*Total Solar Wattage = Energy Consumption / Sun Hours*

*Total Solar Wattage = 400 kWh / 60 Sun Hours = 6.67 kW*

So for this example, the total wattage of our solar array should be at least 6.67 kW (6,670 watts). To determine the number of panels, let's choose a panel size. 

Tiny homes may use panels that are rated anywhere between 100W and 450W. Let's use **400W panels** — a popular choice — as an example. Let's plug that number into our equation from earlier: 

*Number of Solar Panels = Total Solar Wattage / Individual Panel Wattage*

*Number of Solar Panels = 6,670 watts / 400 watts = 16.7 panels*

So, we would need **seventeen 400W solar panels** to fulfill the 400 kWh that we expect to use each month.

### Grid-Tied vs. Off-Grid

Most people dream of an off-the-grid tiny house as an affordable way to live a sustainable and self-sufficient life. If this is in your future, then your energy needs will be different than that of a grid-tied tiny home. 

Grid-tied homes can still pull energy from the utility company. This allows the home to stay powered on even during times of decreased energy production. 

Off-grid homes need to make sure that their solar power system will provide energy at all times. This includes the winter months when sun hours at their lowest and heaters may be in use. An off-grid tiny home can protect against a loss in power by having alternative energy sources on hand, such as wood for heating or propane for cooking.

## Where to Mount Solar Panels for a Tiny Home

There are two main methods of mounting your tiny home's solar panels: roof-mounted or ground-mounted systems. Each comes with its own pros and cons. 

![two tiny homes with solar panels](images/solar-panels-for-tiny-homes/two-homes-with-panels.jpg)

### Roof-Mounted System

The typical residential solar system has roof-mounted solar panels. This is possible due to the large amount of roof space of a normal-size house. With a tiny house comes a tiny roof that usually won't be able to fit enough panels to power a home. 

Not only that, but the weight of the solar array may pose an issue for the integrity of the roof. Each 400W residential panel weighs around 50 lbs. If you are mounting seventeen or more of these panels, there could be a combined weight of 850 lbs or more. Combined with the added weight of snow or other roof fixtures, an array of this size may be too heavy for a tiny home. Be sure to check that your roof has enough area and a high enough weight limit to accommodate a roof-mounted solar system.

Unless the energy usage can be kept to that of an [RV solar system](https://optivolt.com/blog/rv-solar-panels-guide), tiny home owners are better off with a ground-mounted system. 

![solar panels mounted in the ground](images/solar-panels-for-tiny-homes/ground-mounted-solar-panels-grass.jpg)

### Ground-Mounted System

Ground mounting is the preferred installation method for most tiny home solar panels. 

Ground-mounted systems are much more accessible for homeowners. Maintenance and cleaning can be performed quickly and with added safety, as there is no need to climb onto a roof. 

Plus, the angle and orientation of your panels can be perfected as the seasons change and the sun's trajectory changes. In the summer, the sun travels further overhead. During the winter, the sun is lower across the southern sky. Changing the angle of your panels according to these patterns can increase the efficiency of your panels.

You can even make daily adjustments with ease to eek out every last drop of energy during the low sun hours of winter months. This can make the difference between being fully self-sufficient and having to draw power from the grid. Or, it can allow you to go off-the-grid with a smaller array. 

## Conclusion

A tiny home can be energy independent with a moderately-sized solar power system. This allows you to set up your tiny house in remote, peaceful locations. 

[Optivolt](https://optivolt.com) is a leader in solar panel research and manufacturing. They produce innovative energy solutions with the hopes of providing sustainable energy for all.

## Related Questions

### What Are the Best Solar Panels For a Tiny House?

Monocrystalline solar panels are widely-used for tiny homes and provide a good cost-benefit ratio. They are more efficient than polycrystalline panels, but they also cost more money upfront. [Shade-tolerant solar panels](https://optivolt.com/optivolt100) improve upon both technologies and provide added efficiency in partially-shaded conditions. 




A solar-powered tiny home is an affordable way to own a house and get off the grid. Learn how to plan for and add a solar power system to your tiny home.

Solar Panels for Tiny Homes: A General Overview


A solar array is the centerpiece of any solar power system. Harnessing the power of the photovoltaic effect, a solar array is able to turn sunlight into usable electricity for a home or RV. 

The word *array* is used to describe an ordered series or arrangement of objects. **A solar array is a group of solar panels wired together in a parallel or series circuit**. This idea may also be referred to as a solar panel array, or an array of solar panels. 

A similar concept happens on a smaller scale within each solar panel, where individual solar cells are wired together to create a solar panel. 

The **size of a solar array** may refer to the number of solar panels it contains, or the total power output wattage.  

![a glass house with a solar array](images/what-is-a-solar-array/solar-array-glass-house.jpg)

## How Many Solar Panels Do I Need in My Array? 

The average American home consumed 886 kWh of electricity per month in 2021. At this rate, a home may need up to 37 solar panels for full energy independence, depending on the home's location. Sun hours, temperature, and other factors can affect the amount of energy that a solar array is capable of producing. 

In order to determine how many solar panels you need for your home, you need to find out how much energy you expect to use. Look at past energy bills, finding your highest month's usage. Summer air conditioning and winter heating play a big role in energy consumption — make sure to account for this when determining the maximum electricity usage you expect. 

Once you have your estimated monthly energy usage, you can do a simple calculation to determine the solar array wattage needed. Consider this formula:

    Energy Production = Array Wattage × Sun Hours

We will assume the average of 886 kWh of electricity usage and 2 peak sun hours per day, or 60 hours per month (this can vary wildly with location and season). Let's fill in the data we have: 

    886 kWh Energy Production = Array Wattage × 60 Sun Hours
    Array Wattage = 886 kWh ÷ 60 hours = 14.77 kW
    
So, we need a solar array with a power output of 14.77 kW. Most residential solar panels are rated at 400 watts, so let's use that number to determine how many solar panels we need to fulfill an array of 14.77 kW (14,770 watts): 

    14,770 watts ÷ 400 watts per panel = 37 panels    

So, an average American home may need a solar array with 37 panels to completely offset the home’s energy consumption.

Read our [solar array sizing guide](https://optivolt.com/blog/how-many-solar-panels-do-i-need) for a more detailed look at determining the number of solar panels you need. Every solar power system is different. You may need less panels if you receive more sun hours or use less energy.  

Roof space or budget concerns may prevent you from powering your whole home with solar energy. Instead, many homeowners use a small solar array to reduce the amount of power they draw from utility companies. In turn, this lowers their monthly electric bills.

![a solar array mounted on a home with sky above it](images/what-is-a-solar-array/solar-array-on-home-sky.jpg)

## Can You Add More Panels to an Existing Array? 

While it may be technically possible, adding more panels to an existing array is usually not recommended. Trying to do this usually results in more costs and complications than one would imagine. 

When you add more panels to an array, the power output changes. This could result in overloading the current rating of the charge controllers, connectors, or string inverters that are in use. 

Consider these questions if you are thinking about adding more solar panels to your system: 

- Do you have enough roof space for more solar panels? 
- Residential systems usually have an inverter that converts the DC power from solar panels into AC power for the electric grid. Would you need to upgrade the capacity of this inverter? 
- What permits and fees are required? 
- Is the same solar panel model still available for purchase? You may run into issues when trying to use mismatched panels.

If you're still thinking about going forward with adding panels, **consult a professional electrician or solar installer**. Working with high-powered solar systems is dangerous enough, and now you will be attempting to provide more panel output to system components that may not have been designed to receive such power.

## What Direction Should a Solar Array Face? 

A solar array should ideally point in the direction that receives the most direct sunlight. In the Northern Hemisphere, solar panels should face true south. In the Southern Hemisphere, a solar array should point north. 

The tilt angle of your solar array also plays a role in the amount of energy it can generate. In North America, a tilt angle of 40° is a good estimate for year-round power generation. However, there are methods available for determining a more ideal tilt angle that will optimize your energy generation. You can also change the tilt angle of your array with each season as the sun travels at varying paths through the sky.

For a more detailed look at these ideas, check out our [solar panel orientation guide](https://optivolt.com/blog/best-direction-for-solar-panels). 

![a solar array mounted on a gray house](images/what-is-a-solar-array/solar-array-on-house.jpg)

## How Does Shading Affect Solar Arrays?

Partial shading can have drastic effects on the output of a solar array. Depending on the way that your panels are wired, shading on one panel can affect other panels in the array. 

The negative effects of partial shading begin at the panel receiving shade. The individual cells of most solar panels are [wired in series](https://optivolt.com/blog/solar-panels-series-vs-parallel). Due to the nature of series circuits, the voltage of the cells are added up while the current (amperage) remains the same throughout. This means that if one cell is outputting a lower current, the rest of the cells are brought down to the same current. *A solar panel is only as strong as its weakest link*. 

This same concept applies to solar arrays that are wired in a series circuit. When one panel becomes shaded, the rest of the panels' currents are brought down with it. 

There are a few ways to combat this shading issue, including using a parallel circuit and shade-tolerant solar panels. The [Optivolt 100W solar panel](https://optivolt.com/optivolt100) solves both of these issues. The panels feature their innovative Pulse technology that produces up to 60X more power in shade when compared to traditional solar panels. 

Plus, these shade-tolerant panels are designed to be wired in a parallel circuit (in which the currents are added together and the voltage remains the same). The high-voltage version allows more panels to be wired together in parallel without raising the current to excessive levels. 

## Key Takeaways

Here are the main ideas to remember about solar arrays: 

- A solar array is a group of panels wired together in series or parallel. The collection of panels generate electricity as a system, much like how dozens of solar cells make up a single solar panel. 
- You may need a few dozen panels in your solar array to produce enough energy for the average household. However, even a small solar array will have a big impact on your electric bills. 
- Adding more solar panels to an existing array is a complicated, potentially-dangerous process. Consult a professional before attempting to do so. 
- In the Northern Hemisphere, your solar array should be facing true south to maximize energy generation. 
- If one panel in an array is shaded, the rest of the connected panels may be affected. Shade-tolerant solar panels and parallel circuits can mitigate this issue. 

[Optivolt](https://optivolt.com) is a technology company providing resilient, sustainable energy solutions for humans. Their unrivaled Pulse technology is integrated into their 100W shade-tolerant solar panels, paving the way for solar arrays to produce more energy in adverse conditions. 


A solar array is a group of solar panels wired together into a circuit. Learn more about the sizing, safety, and power optimization of solar arrays.

SOLAR 101