10 great uses for a 20A solar charge controller

A 20A solar charge controller gives you more room to build a useful off-grid system. It can handle a larger solar array than a 10A or 15A controller, making it a great choice when you want to put the sun to work for you.

1. Powering a caravan or motorhome
   Keep your leisure battery charged while you’re travelling or enjoying a few days away from the mains. Perfect for lighting, USB charging, small appliances and other everyday essentials.
2. Creating your own garden power system
   Turn a shed, workshop or garden building into a useful off-grid space. Solar energy can provide power for lighting, charging equipment and other low-energy devices.
3. Remote security and CCTV
   Put security cameras exactly where you need them, even when there is no convenient mains connection. A solar panel, battery and 20A controller can create a completely independent power supply.
4. Keeping boats powered up
   A 20A controller can help maintain a leisure or auxiliary battery on boats, giving you a dependable source of stored solar energy when you’re away from the marina.
5. Running remote lighting
   Illuminate gates, pathways, outbuildings, garages, signs and other locations without digging trenches or running long mains cables.
6. Powering electric fencing
   Solar power is particularly useful for remote electric fencing where running mains electricity isn’t practical. The battery stores energy ready for use when the sun goes down.
7. Building a camping power system
   Take your own power with you. A solar panel and battery system can provide energy for phones, tablets, LED lighting, radios and other camping essentials.
8. Off-grid workshops and garages
   A 20A controller gives you more capacity for a useful workshop battery system, helping to power lighting, charging equipment and other smaller electrical loads.
9. Remote monitoring and communications
   Solar power can keep weather stations, sensors, monitoring equipment and other remote technology running without relying on a mains supply.
10. Creating a reliable battery backup system
    Keep a battery charged and ready for when you need it. This can be useful for emergency lighting, communications equipment or other essential low-power devices.

How much solar can a 20A controller handle?

A typical 20A charge controller can provide up to 20A of charging current to the battery.

For example:

20A × 12V = approximately 240W

So, in a typical 12V system, a 20A controller could be suitable for a solar array around 200–240W, depending on the controller’s specifications.

However, don’t choose a controller based on wattage alone. You also need to check the controller’s maximum PV voltage, battery voltage and whether it is PWM or MPPT.

Bigger than the basics

The real advantage of a 20A controller is flexibility. It gives you more solar charging capacity while still being compact enough for caravans, boats, workshops, sheds, remote buildings and small off-grid systems.

Capture the sunshine. Store the energy. Use it when you need it.