Solar PV quotes - 4.9 kW system but 3.6 kW inverter?
Hi everyone,
thought I'd ask the hivemind what you thought of the solar PV quote I've received from a company with decent reputation locally. For our east/SE facing roof, they've proposed
- 12 x 410W Hyundai panels
- 3.6 kW Growatt hybrid inverter with 6.5 kWh battery
For £9.9k plus VAT. It's not the cheapest quote I had so far, but from what I gather the Growatt system is better than e.g. GivEnergy.
What I found surprising is that the inverter is smaller than the entire system, and my understanding would have been that the panels, on a sunny summer day, would be able to generate ~4.74 kW but the inverter would only make use of 3.6 kW at any time. Having spoken to the company about this, they argued that a larger inverter would come on later in lower light conditions - e.g. a 5kW inverter would not allow us to generate as much in winter, where it arguably mattered more to squeeze out any last bits of efficiency. An additional factor would be the DNO of course. In their opinion, the efficiency gains in lower light conditions would make up for the restriction in peak output.
Curious to hear everybody's thoughts, and if you had experience with Growatt systems then even better!
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