Solar Balancing is a Power Management feature. The point is to only charge on excess solar power that would otherwise be fed back into the grid. To use Solar Balancing, a meter must be installed.

There are 2 Power Management modes for Solar Balancing:

These modes are group based, so you find them in the location settings, not in the charger settings.

Solar backup usage (Solar Only)

Your car needs at least 6A per phase to charge. So in Solar Only, charging will only happen if there is at least 18A of excess solar power available. If this is not achievable, you can allow the charger to pull some electricity from the grid to ensure a smooth charge.

This setting is considered as a sum of all power that may be pulled across all phases.

Minimum Charge Threshold (Smart Solar)

By default, the charger will always offer 6A to the car in Smart Solar. If this is too low, you can increase this value with this setting.

There are 2 main goals:

We call this "net zero", or "zero at the meter". No usage and no surplus.

We can achieve this by charging the car at the right moments. Effectively, we're only charging your car if you would have otherwise lost solar power to the grid.

Think about it, we don't really need to know how much solar power you are producing. All we must know is how much surplus solar power is being put back into the electricity grid. And we can see that by just checking your main fuse with a meter. No extra metering required!

So let's take the scenario from our Load Balancing article.

The last one is a big factor for solar balancing.

Now, let's imagine you have solar panels and they are producing 10A. You are using no power in your house whatsoever. This means the 10A is directly flowing back to the grid, we consider this a "negative" consumption.

The blue line represents your power consumption:

But this isn't realistic. You are constantly using power elsewhere in your house When you are cooking, washing your clothes, etc. And clouds are constantly moving in front of the sun, too. So it may look more like this, so between 8:20 and 8:40 you are even using power, instead of delivering surplus:

Remember, the goal is to not use any power from the grid and not to deliver your solar power to the grid. So you want your effective usage to be zero.

In other words, when the blue line is below 0A, you want to charge, and if it's above 0A, then you want to stop charging.

So this is the perfect scenario, where the charger (green) perfectly saves all your solar power (blue):

Let's introduce an orange line to represent the effective usage. So we're at 0A the whole time, but at 8:30 you are using power and we cannot prevent that. To cancel out this peak, you would to produce extra power for your home, for instance with a V2G charger or home battery system.

Unfortunately, the scenario above is not possible because the car cannot charge below 6A. Strictly speaking, if we stop charging below 6A, the graph would look like this:

Between 8:15 and 9:00, we are producing less than 6A energy surplus. Sure, we are producing some surplus, but not enough to charge the car, and this surplus is now being wasted to the grid.

So what can we do? It's time for a Solar Backup Usage setting. By mixing grid power into the charge, we can still charge the car. For example:

If the surplus is only 4A, we will charge at 6A. Yes, you will be using 2A from the grid, but at least you are not wasting the 4A of your own solar power.

You can play around and decide what's best for you. For instance, if you only have a surplus of 1A, is it really worth pulling the extra 5A from the grid? Maybe it's better to just wait for a bigger surplus.

Let's go back to our scenario and choose a mix mode of maximum 33% grid power, in other words, we will never pull more than 2A of grid power. Effectively, this means you need a surplus of 4A to start charging.

Much better!

There's one more mode to talk about, and that's Smart Solar. In this mode, the charger will always charge at a minimum 6A, even during the night. This is a nice mode because you don't have to constantly think about switching modes. If there wasn't enough sun during the day, the rest will be charged at night.

Of course, there is more surplus than 6A, for instance 8A, the charger will increase its charging speed to 8A to prevent wasting solar power. This is how it would look:

Is 6A too slow for you, or for your car? Try increasing this by using the Minimum Charge Threshold setting.