You’ve probably seen it. It shows how the price of solar PV energy has come down in an almost vertical line over the past 25 years, while conventional sources of energy have generally been rising slightly.

Even as oil seems to have entered a “lower for longer” era of ostensible cheapness it, and indeed no other fossil fuel, can compare to solar prices as low as 3 US cents in sunny areas and even 8 cents in not-so-sunny regions like Germany.

What’s