The European Solar Test Installation (ESTI) has confirmed Longi's achievement of a world record-breaking efficiency rating of 34.6% for a perovskite-silicon tandem solar cell.
My panels are 12 years old and approx. 12% efficient, treble the power from the same roof space would be a very tempting upgrade, as long as the price does not go up too much.
I just looked it up and it’s actually rated at 14% peak, but no it’s just the 2010/2011 series of Polycrystalline cells, it was a premium panel when I bought them.
I always remembered then to be somewhat better than those numbers and this paper agrees with me (figure 1). 14 % is not premium (efficiency) for polycrystaline in 2010. Figure 1 shows 20 % for polycrystaline at 2010 and 25 % for single crystal. Thin film, on the other hand, is down there at maybe 15 %.
In 2011 in my Region of the world (Europe) there were no commercially available panels to buy that could hit anywhere near 20%
I’ve not read this paper fully but I suspect it’s referring to lab testing, or panels produced in small numbers and 10x the cost of all other panels. Mine were REC240PE for reference.
Edit: that chart is titled “Best Research-Cell Efficiencies” so this is lab testing and it’s exactly the point of this thread… “35% Efficiency, Why is this not in stock at Costco!?!”
You are correct! Sorry for mixing this up. I must have looked at research Numbers back in the day and simply used that as my reference now, which of course is then correct if look at research again...
No problem, I remember researching the available panels at the time and selecting the most efficient and playing panel Tetris to get the most possible on the roof.
In the end the installer did a last minute switch, but although the panels were not the best available they were pretty close. The most annoying thing was that the panels were slightly different dimensions and the installer insisted in wider margins around the panels so I ended up with several fewer panels overall, ruining my carefully planned layout.