Here in Britain, solar power is much more effective in the summer. The days are longer, and in mid summer solar PV produces five times as much energy as mid winter. Inconveniently, we also need more energy in winter, to heat our homes or to light them on those longer nights. Wind power picks up some of the slack, but we still need rely on fossil fuels to get us through the colder, darker periods of the year.
From a British perspective, it’s hard to imagine that solar power could run the world. But that’s what commentators like Jeremy Leggett or Chris Goodall suggest. Wild variations in light levels happen the further North or South you go, and the world’s population is concentrated in the middle. Most of the world doesn’t need to worry about solar being ineffective for half the year. It can provide what they need all year round.
With the price of solar panels falling so sharply in recent years, and batteries set to follow, most of the world’s population could rely on solar power, with wind and hydro power picking up the rest.
That claim was reinforced recently by a Stanford-led study that looked at the energy needs for 139 countries, and discovered that every one of them could run on 100% renewable energy by 2050. The exact energy mix varies for each country, but solar provides the majority. That’s for all energy use too, it’s worth noting – not just electricity. Transport would be electrified, and because electric forms of transport are more efficient, the amount of energy we need falls and that makes it easier to hit that 100% target.
A global shift to clean energy like this would keep climate change within 1.5 degrees of warming, save millions of deaths a year from air pollution, and be a net creator of jobs. Spread the word – a full transition to renewable energy is possible, and it has multiple benefits.