On the average day from late March through to mid-October you’ll probably generate more electricity than your house will consume. On a sunny day, you’ll generate a significant excess of electricity.

However, during the winter months, and in particular December & January (in the UK), you’ll generate much less electricity. Even a sunny day in January doesn’t generate that much electricity, because the sun is low in the sky and because the daylight hours are so short. The opportunity to generate electricity is limited to the period 1030-1430 hrs. That is a 4-hr window of opportunity, with the remaining 20 hrs unable to contribute anything.

Can I use the power generated?

The other consideration you have is whether you use the power that is being generated? We already noted that in the period April – September, you’ll probably have an excess of electricity. So how to use it becomes the next question. If you have a solar diverter (such as an eddi generating hot water) or a compatible Smart EV charger (such as a zappi or an Indra) you could soak up most or all of that excess into your Electric Vehicle – and benefit from free miles.

In the Winter, you might generate enough electricity to run your house on during the small window of time that the sun is out. But if you can’t use it at the exact moment it is being generated, it is wasted (sent to the grid).

A closer look at your dishwasher’s power consumption

Here is another way to think about this. You’ve put the dishwasher on. Unless you have a way of monitoring the power usage of that appliance, you don’t really know how or when it uses power.

Have a look at this graph:

What we have here is the power usage of a standard dishwasher on a 50 degree cycle. The total energy used was relatively small at 1.16 kWh. So even during winter our Solar Panels should easily handle this. They can certainly generate more than 1.16 kWh, even on the cloudiest of days.

However, when we look at the chart, it is immediately apparent that the dishwasher consumes power in 3 distinct bursts. It does not consume power consistently throughout the cycle. This is obvious when you think about it, and relates to when the dishwasher is heating water at the beginning of the cycle, the rinse function towards the end, and finally the drying cycle.

So, was the dishwasher powered using solar power or not?

Let’s overlay the energy monitoring graph over the graph from the inverter:

In this graph we can see that for most of the dishwasher’s cycle, the Solar Array was delivering more than enough power.

But at those critical moments when the dishwasher is heating water or drying the dishes at the end of the cycle, it is consuming more power than our solar panels are generating.

Ironically, the power demand of the dishwasher is completely out of synch with the Solar Power!

Home Storage Battery

The only sure-fire way to marry up these two graphs is to have a Home Battery Storage solution. That way you can be sure of running off solar power throughout the cycle, without having to draw from the grid.

The battery allows you to align consumption patterns with generation. The aim of the game with solar is to maximise your self-consumption, and therefore minimise your reliance on the grid.

Giv-Bat 8.2

The 8.2kWh battery pack sits alongside our AC Coupled or Hybrid Inverter so that you can store energy from the grid or excess generation.