Retrofitting SolarEdge system to Single inverter Solar panels

Hi there
I have had a surveyor round today convincing me that it is worth paying £4995 to upgrade my 16 south facing Single Inverter solar panels to SolarEdge ones. His argument was convincing, as I don’t feel the solar panels are generating as much energy as I was promised in August 2015. Please advise whether I should go ahead with this upgrade.

SolarEdge micro inverter or optimizer ??? if it just the optimizer then i would wait the ~5 year more for your string invert to come close to end of life then switch over to micro inverter… personally for me i would go with the 1200 watt units that tie 4 panels together their cost is about $400 per unit you can usually tie 4 units together to a single 30 amp breaker. as I assume these panels are probably around 200watt . so the life span of the micro inverter will be close to 25 years at 60% loading… and generally you get 20% more power out of micro grid tie compared to string and personally I think optimizer are a waste of money as you can get micro gTi for the same price as an optimizer – but hey that is my opinion the choice is yours to make

What was his argument?

That seems a lot of money. Is he suggesting replacing your panels, or simply bolting a SolarEdge optimiser to the bottom of each of your existing panels, and swapping out the inverter for a SolarEdge inverter? AFAIK, you can use any old panel with their per-panel optimisers.

That per-panel stuff, be it optimisers (DC) or micro-inverters (AC), really comes into its own when you have a challenging roof, so the answer probably depends on what your roof looks like.

Here’s mine from space:

Judging by the shadows I’d guess that was taken mid-morning in winter (I’m in the southern hemisphere). That larger panel on the lower northern roof (partly shaded by trees in this photo) is the solar thermal hotwater collector, not PV.

The challenges here include the lower northern roof gets partial shading from some big gum trees, especially in winter. The lower eastern roof gets shaded by the upper storey after about 1pm. The rake of the upper roof is very different from that of the lower roof.

The SolarEdge stuff does a pretty good job at dealing with all that. Here’s my per-panel energy output since install (about 5.5 years ago):

And I’m not yet noticing any significant degradation of panel peformance with time, so hopefully he’s not suggesting replacing your panels:


Yes it does now seem a lot of money for simply bolting a SolarEdge Optimizer on to each panel ( which he said are good quality ones), and changing the inverter. Our panels are all at the same angle and side by side, so not a challenging roof at all, and barely
affected by shade, when the sun actually does shine in England! I feel he has tried to con me out of a lot of money for very little energy efficiency savings.

Thanks for your information and advice