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Looking after your House Batteries and understanding more about your Solar Panels

This article explains how to keep your house batteries in the best condition while at home and on the road and some interesting information about your solar panels.

There are three main ways to charge your house batteries.  Plugging into mains power, solar panels and driving while using your alternator.



There are many factors that can affect battery life. These include discharging the batteries below 12.2V, not fully charging the batteries at least once a week, very low temperatures, heavy discharge without full recharge or storing your motorhome or caravan without fully charging the batteries first.

We recommend extending the life of your batteries by using the built-in mains power charger whenever you have an opportunity. In low light conditions such as winter, you may need to plug into a mains power source for 12 – 24 hours at least once a week to ensure the batteries receive a full charge. In these conditions solar power may not be enough to give the batteries the regular full charge they require to ensure long life.


Solar Panel Facts

Solar panels will feed your house battery continuously without you needing to turn any switches. So you should be all sorted right? Yes and no...


So how does it all work?

Solar panels produce electricity in direct proportion to the amount of sunlight on the panel. The angle of the sunlight falling onto the solar panel will determine how much energy will be generated. The highest absorption of sunlight will occur when the light intensity is at its highest point (from midday to early afternoon) with the sun falling directly (50° to 60° angle) onto the solar panels.

As the sun slowly goes down, the angle will flatten and the absorption will be less. Once the sun is down, there will be no light absorption at all.

In summer on sunny days you will be able to get much more charge than on cloudy days or winter times. In winter, you can have days or even weeks with little to no sunlight. The little sunlight you may get is not likely to be at an optimal angle. This will result in much less energy absorption as on sunny days.


What does this mean?

You need to be aware of the fact that the sun is not always feeding your solar panels- you’ll need to adjust your power consumption accordingly. It pays to be a bit more frugal in general with your energy use when bad weather is ahead or in the winter months. Avoid using your inverter (if you have one), and refrain from using all your lights at once. A perfect example is a situation where you would be freedom camping in the South Island in the middle of winter with only rainy days ahead and no driving because you like the spot so much, you would like to stay for a few days. Using the microwave or charging your e-bike batteries on your inverter and having all lights blazing like a disco party would not be a very good idea- the lights will eventually go off (and sitting in the dark is no fun!).

Even in summer, it’s good to be aware. You need the sun to hit your solar panels head-on, so choose your campsite wisely with no obstructions like buildings or trees that can cast a shadow onto your roof. Trees shade the sun and bird droppings will compromise the energy absorption of your solar panels, so keeping the panels clean is also very important!

Once you understand how the sun works with your panels and you adjust your energy consumption, you will be well prepared for your travels.


So what’s the best practise of care for my motorhomes’ power systems?

Plugging into mains regularly is very important for your batteries, especially AGMs, as they will need to be kept topped up to avoid reducing their lifespan. Solar will, in many situations, not be enough to achieve this. Even Lithium batteries will need re-charging via mains, so that you can continue to utilize their capacity to its fullest, especially in spring/autumn/winter months. Your solar panels will assist in charging your battery alongside.

Remember, driving will charge your house battery via the alternator and better still, find a great campsite with a powered site and plug into mains and give the battery a chance to fully charge up again.