Welcome to the world of solar energy. Many people have been using solar panels for decades, but it’s only recently that you can buy them at your local hardware store. With so many options out there, it can be hard to know what you need and how to set everything up.
Here are some frequently asked questions about connecting your RV with solar power.
Do You Need A Solar Charge Controller For Rv?
You might be wondering if you really need a solar charge controller for your RV. It depends on what you want to do with the battery and how much money you want to spend. If you want to charge your battery using solar energy, then yes, you do need a solar charge controller.
The device will make sure that enough power is getting into your battery for it to be charged properly. Without one, charging could take longer than expected or even damage the equipment inside because there won’t be enough electricity flowing through it at once, which happens when too many current flows from one place.
Can I Connect Solar Panel Directly to RV Battery?
You can connect solar panels directly to RV batteries. However, you will not get the full potential of your solar panels because the battery voltage is too high, about 13.6V.
You can use a charge controller, or you can use a battery isolator. A charge controller will limit the charging voltage so that it doesn’t exceed 13.6V and damage your batteries. A battery isolator allows you to charge both house and engine batteries while they are connected in parallel but isolated from each other during discharge.
This means that when one bank drains down below 12V, it’s isolated from draining into the other bank which remains at 13+ volts all of the time, assuming both banks are kept charged.
What Happens If I Connect Solar Panel Directly To Battery?
You can connect your solar panel directly to the battery. It will not charge at a fast rate and you will need to connect a charge controller. A charge controller is an electronic device that converts the direct current (DC) output of a photovoltaic panel into an alternating current (AC), which can be used by the battery charger.
The charge controller should be connected in series with your panels and connected either directly to the batteries or through an inverter/charger combo unit, which we recommend in most cases as it makes monitoring much easier and allows you to use power from shore power when available.
If done improperly, you could damage both yourself and your equipment so please make sure it is installed correctly.
Do I Need an MPPT Controller?
In short, yes. A PWM controller is great for small solar arrays and off-grid systems, but if you have a larger system or want to be more efficient, you’ll want to use an MPPT controller.
But how much more efficient is the MPPT controller? According to the folks at Solar Charge Controller Reviews, “a good rule of thumb is that an average 80-watt solar panel will produce around 50 watts at the maximum output during mid-day sun conditions in full sun, one hour after sunrise.
If we take this 50 watts and divide it by 80 watts, a typical power rating for a 12-volt battery, then we get 0.63 amps per watt which means that it would take about 6 hours for one hour’s worth of sunlight on this particular type of panel before you could fully charge your battery if using no other equipment like inverters or charge controllers.
This doesn’t mean that you should buy an expensive MPPT controller over something cheaper. It just means if you’re considering upgrading from a $30 PWM controller to something more advanced like an HQRP 5A Smart Solar Charge Controller, there’s some math behind why doing so may benefit your battery life and efficiency over time.
Does a 7 Watt Solar Panel Need a Charge Controller?
A 7-watt solar panel will charge your 12V battery faster than a 5-watt solar panel. The reason for this is that the increased wattage allows for more current to be generated and transferred to the battery, resulting in higher power output.
However, there are other factors that may affect how quickly your RV’s 12V battery charges from your 7-watt solar panel:
- The size of the RV’s storage compartment
- The size of the storage compartment (can determine how fast you can charge your battery when using a low-rated device like a 7W solar charger. For example, if you have an RV with limited space inside, then it may take longer than expected to get enough power stored up in its batteries just because they won’t be able to create as much energy as they would if they were able to sit out in direct sunlight all day long without getting bumped around too much by their surroundings. This is why many people choose not only where they park during their vacation but also when it comes time for them to set up camp outside; some places will receive more sunlight than others.
Will a 5W Solar Panel Charge a 12V Battery?
Yes, it will. A 5W solar panel can sufficiently charge a 12V battery. So if you have an RV with multiple batteries and want to save some money on your power bill, this might be the way to go. A smaller solar panel could work too, but depending on how much energy you need for your RV, it may not be worth it for all of those batteries.
If you use more electricity than what comes from one small solar panel, probably not many people do, then consider getting multiple similar-sized panels instead of one massive one that weighs down your roof rack by itself.
Will More Solar Panels Charge a Battery Faster?
If you have more solar panels than the controller can charge in a day, you will need to either use a larger controller or run multiple controllers. In other words, if your system has 5 panels and the controller can only charge 4 at a time, then you will need two controllers so that they can both be used at their maximum capacity.
It’s also important to note that most solar charge controllers are designed to work with one panel per branch, a branch is a connection between one set of connectors on the back of your controller.
If you have multiple branches coming off your main solar panel lead and want those branches connected together into parallel circuits, then it’s possible for up to 8 or 12-volt systems by using some kind of junction box called an interconnect box or combiner box.
We hope that this article has helped you understand the difference between a charge controller and a solar panel.
We also hope that you are now able to make an informed decision about whether or not you need one for your RV battery.