The solar game is all about the numbers. Before you buy panels for your roof, you do the maths – how much? How long to pay off? Can power prices really keep increasing?
On a broader scale, power utilities are also furiously doing the maths on the solar equation. Will there be mass uptake? Is this really a solar boom, or a flash in the pan? Just how low will panel prices drop?
The first lot of questions are straightforward. The second are harder to predict, but early indications are that any forecasts will be so undercooked as to be comically so.
The estimate made in 2000 that by 2010 global solar installations would reach no more than one gigawatt proved to be incorrect by a factor of 17. And then panel prices fell through the floor. China alone says that three years from now it will be producing 70 gigawatts.
The great, hopeful news in all of this is that coal gets struck squarely in the breadbasket. It is used for producing electricity around the world and is responsible for 45% of the world’s greenhouse gas emissions.
The same amount of energy falls upon the earth as sunlight every hour as we use for the entire year. Do the maths. Those panels on your roof might just save the planet.