It's looking like solar panels are set to double in efficiency quite soon, a new technology "Multi-Junction Solar Cell" will take it from 20% (today) to 40% in the future. It works by using layers to absorb different wavelengths of light.

Hopefully we will see these panels being sold and fitted to buildings in the not too distant future.

I thought they've been around for a while now. The problem is cost of manufacture. Most home panels are 20-23% but are relatively cheep. I think there are some premium ones at 30%.
I think there are some weird and wonderful small EV panels approaching 50% but if they cost more than twice as much (I expect much more) they are not going to get to market.

Still a lot of roof tops out there to fill. Even at 20%, that's a fair few gigawatt. I think the standard panel used to be 250W (or there abouts) but seems to be 300-400W now.

Quote from: Snowcrash on August 25, 2021, 17:20:43 PM
Still a lot of roof tops out there to fill. Even at 20%, that's a fair few gigawatt.

Indeed, if every house that could have solar actually had them fitted it would have a huge impact.