Inverters have more electronic parts, but the parts themselves are very off-the-shelf, and the electronic design is pretty straightforward.
Inverters are still fairly expensive for a couple reasons;
Firstly economies of scale. A residential site buys 1 inverter, but 10 to 20 panels. A commercial site has an even bigger ratio.
Secondly Inverters are the bit that connects to the grid. So there are regulatory requirements which need to be tested for. And likely tested in multiple different jurisdictions.
Panels on the other hand are "difficult" to produce in volume. Largely because of the quality of raw silicon that is required. Its not that the panels themselves are complex, but the supplier chain to them is.
Sure but with a 20 year life span it's not like you can easily cut people off from the them. An interruption in supply has an enormous lead time to build a solution.
Panels are often quoted has having a 20 year (or 25 year) lifespan. But it doesn't really work like that.
Panels degrade a bit (about 0.7%) every year. So after 25 years or so they're down to 80% of rated power. Or, put another way, after 25 years they're still delivering 80% of rated power.
Depending on space, it may be advantageous to replace panels at some point. Or you might add more and leave those alone.
But they don't just "stop working" - the performance drop off is pretty linear.
Inverters are still fairly expensive for a couple reasons; Firstly economies of scale. A residential site buys 1 inverter, but 10 to 20 panels. A commercial site has an even bigger ratio.
Secondly Inverters are the bit that connects to the grid. So there are regulatory requirements which need to be tested for. And likely tested in multiple different jurisdictions.
Panels on the other hand are "difficult" to produce in volume. Largely because of the quality of raw silicon that is required. Its not that the panels themselves are complex, but the supplier chain to them is.