Exporting Solar PV

April is a great month for Photovoltaic (PV) owners. It represents the flip-over from taking energy from the grid over winter to exporting it back during summer. Or spending loads on electricity to selling it back to your supplier. Yippee!

Let’s look at these extracts from our home’s 4.4kWp system for the first 4 months of 2024:

Looking purely at the total energy use (Load Consumption) versus how much the solar contributes, for Jan and Feb the PV contribution is around 30%. March increases to c.90% and April shows the amount we generated ourselves outstripped our total usage.

Same graph, different metrics. This compares the amount we paid to the grid and how much we sold back. We sold virtually nothing in Jan & Feb, and 50% in March compared to what we bought. Yet by April we sold three times what we bought. We buy c.£0.25 and sell around £0.15 (although factoring in the standing charges it’s maybe break even for April). We’ll start to earn money from here on until it drops back again around October.

This third graph shows the energy we produce off the roof versus what we bring in from the grid. For Jan & Feb we needed to import far more than we produced. March was the flip month this time, the exact reverse of the month before. By April, we’re laughing; the PV production is nearly 10x what we’re buying in from the grid….and it’s not even summer yet.

Looking at last year in retrospect, we see the expected Bell Curve showing higher solar production (green) in the summer months and when exporting (purple) kicks in between April and Sept/Oct. This demonstrates that April is the first month of proper monetary payback from exporting your energy.