About Off-Grid Solar Power
Off-grid solar combines electrical components to create and supply power without needing a mains connection.
This solar power system covers four components: the solar panels, the batteries, a charge controller, and an inverter.
The solar panels on your roof convert the sun’s rays into power, feeding it into the charge controller. This component controls the power going into the batteries to charge them up to 100 percent safely. Then the inverter takes the energy stored in the (48V DC) batteries and turns it into power for everyday household appliances, typically (240V AC).
Off-grid solar stores the energy from the sun’s rays in batteries; this explains the main difference between grid-tied and off-grid solar; the grid-tied solar system doesn’t store any energy for later.
To understand this system more straightforwardly, you can think of it as water collection.
The solar arrays are like a roof area that collects the rain, and the system’s battery unit is like a water tank that stores rain caught on the roof. When raining, water fills up the tank at a rate in proportion to how heavy it is raining. A more extensive roof allows you to catch more rain, even when it’s drizzling than you would with a smaller roof.
This process is the same for solar panels. More solar panels on your roof mean catching more energy on cloudy days than you would with fewer panels.
In saying that, an increase in batteries in your system is the same as having a bigger water tank. You can store more power and have it available when there is less sun. The downside to a more significant battery bank is that it takes longer to charge if the solar array is undersized to match.
A water tank can be half filled, but if you leave batteries in a partial state of charge and slowly charge them up will reduce the batteries lifespan.
In this water collection analogy, the solar charge controller represents a valve that regulates the tank’s water flow, stopping it from overflowing. It ensures an evenly charge at the current voltage and current, up to 100 percent. When they reach this percentage, the controller will cut off the power to the batteries, and when using that energy, the charge controller component will top the batteries back up when the sun comes out.
The batteries store the energy as direct current, so an inverter is needed that turns that energy into alternating current at 230V to mimic the grid power to power your standard household appliances. Both the inverter and charge controller must have the right size to match the solar array and battery bank.
The larger your battery bank and solar array, the bigger your charge controller needs to handle the extra energy that will run through it.
The inverter affects how much stored energy you can use at once. It should have equal voltage as the battery bank. The size is set on what you will power with your solar kit. A larger inverter is needed to run a high-power item like a microwave or multiple devices or appliances at once.
It is recommended to have an inverter large enough to handle all your power needs; otherwise, you might risk accidentally using more energy than you wanted to, just because it’s there.
Learning about the different types of solar power systems can be technical and confusing, so feel free to contact us if you need help figuring out the right solution.