The use of solar panels in households is getting popular. This is because of the benefits that you can get from it. But not all its users have the complete knowledge to surely optimize their usage. People just love it mostly because of the freedom that it gives when it comes to having your source of electricity. It is so useful especially in situations wherein there is a power outage in your area. But the question is how many watt solar panel to charge deep cycle battery? Once you already know it you’ll be sure that you get the efficiency that you are looking for.

Why batteries are highly-important in solar panels efficiency?

By not relying completely on grids you’ll surely reach the goal that you want in having an energy-efficient home. In this article, we will prove it to you that a solar panel can work wonders especially if you know the complete details in charging a deep cycle battery.

This is because batteries are where the energy acquired is stored and it is only fair if you’ll use the one with fully-functional components. As a result, you’ll surely get the sufficient energy you need in case there is a power outage in your place.

The thing is for you to know if the battery will be efficient is by knowing more info about its batteries. This is why we have decided to write this article to you regarding deep cycle batteries.

Some professionals use second-hand forklift batteries because they are more cost-friendly and has huge energy storage. This is why knowing the watt requirement of a deep cycle battery charging is truly important. It will help you gain a very useful and efficient solar panel system in no time.

Learning the Calculation Process

Calculating the solar power requirements is easier than you think; you must just be keen on details. This will help you get results that are précised to your energy needs. So you’ll surely run your entire household with off-grid power without problems.

There is a formula that is used to calculate it. The battery’s storage capacity is the primary way that is needed to obtain a highly-efficient solar panel system.

The battery storage will be determined by the use of Ampere hours which will be turned into Watt-hours. Then it will be multiplied to the voltage. That is the main explanation for the formula beneath:

Power (Wh) = AH x Battery voltage

For example, you possessed a 20 Ah capacity 12v battery. You can transform its capacity using that formula into Wh. So if you will get the answer it would be 240 Wh for the given example above.

However, the energy stored goes down over time that is why you need to use it. You must also be mindful that every appliance has a voltage requirement and to run them they must reach the adequate voltage required.

How to know the voltage requirement of appliances?

It is essential to know the individual pieces of appliances that you have on your home. By doing so, you’ll be able to have an estimate of how much battery power you’ll need. Aside from the mere power numerically, we will also have an idea of how long will they last if an off-grid situation happens such as power outages.

The formula is pretty simple and can be computed easily. You will just need to follow the given formula below.

Wh = Watts x Hours of Use

The watt-hours signify the appliance that you will be using. The computation can be done in just a few seconds but you must compute the appliance individually which is the one that consumes more time.

Also, the rating of the solar panel can be calculated. This will help you know if it can supply sufficient power to your appliance. The formula explains that you have to multiply the generated power of the panel by the amount of time it was exposed to solar energy.

Energy generated = power rating of a solar panel (watts) x time exposure (hours)

One concrete example is if you have a 10w power rating and it has a 6-hour exposure to the sun’s rays. You can multiply it to each other which will give a product of 60 Wh.

The Wattage Needed for Battery Charging

Now the big question is the wattage requirement for battery charging. With the factors that we have discussed a while ago, we can be able to determine that. The computation is very doable as it can be understood by normal people like us.

The prior step that you must undertake is by knowing the Ah or amp per hour of the panels and dividing it to the energy rating by the battery’s voltage. You should put up 10 percent charging time on the result. To make things simpler, the formula is given below.

Average charging time = max capacity of the battery (Ah) / Solar panel’s amp rating + 10% Charging time


It is quite complicated at first to compute for how many watt solar panel to charge deep cycle battery but if you will just use the formulas we gave a while ago it is possible. You’ll just have to find out the numeric factors correctly to get accurate results. Lastly, what can you get, by knowing the computation? You can buy reconditioned batteries for a low cost without compromising results thus giving you the grid freedom that you always wanted.

See more:

How to Use Solar Panels During Power Outage?.