How often do you clean your solar panels? Spare a thought for the poor sods in the Middle East, India and China, where migratory dust coats solar panels and hangs around in the air, blocking incoming sunlight.
Researchers in India who cleaned their panels every few weeks and discovered that they got a 50% jump in efficiency each time. If the cleanings happened every two months, the total losses were 25 to 35 percent.
The article very much blames human pollution for half the capacity loss, but in the detail, the press release admits that 92% of the dust on each panel was natural. Apparently human made particles are smaller and stickier which makes the 8% human-emitted-dust equivalent to the 92% of other dust.
Either way, real pollution and natural dust will slow the clean-green-energy future in India and China until we get auto-cleaning panels or roof slaves. Unfortunately, cleaning panels also risks damaging them, so the price of solar power really needs to include the cost of windscreen-wipers/slaves, electricity losses, damage to panels, and damage to the panel cleaners too.
But solar panels will definitely power all the other parts of the world that are near enough to the equator and not in the path of flying dust, pollution, or under too many clouds, and especially those with electricity demand that peaks at 12 noon daily, which no modern country does.