Most people don't realize how different solar isI've been writing a lot about solar power lately, but I think there's a challenge in actually conveying just how important that source of energy will be for humanity in the near-to-medium-term. I wrote about how rooftop solar PV will reach grid parity in most US states soon, how experts have hugely missed the market trying to forecast solar prices (they were too pessimistic by 59% just in the past 4 years), and how in just 9 years worldwide solar power capacity went up by 53x (and from 5 GW in 2005 to almost 200 GW by the end of this year!). I've often pointed to some of my favorite graphs (below) showing the cost of solar power plummeting rapidly over the past few decades and the number of efficiency breakthroughs for various solar technologies.
But I think that even after seeing all that, most people kind of expect the future to be like the past, with slow changes to our energy supply. I think we're in a non-linear system where seemingly nothing happens for a very long time until certain conditions are met and then, BOOM, things start to happen really fast and we get into the steep part of the exponential curve.
So back to the graph at the top of this article. Why is it so amazing? It shows the price of various energy sources since the late 1940s, and as you can see, at that scale there isn't much variation. Even oil's big moment in the 1970s embargo and in the recent years look like pretty small bumps in the road. And then you have solar power that comes in crashing down toward the end. Before then it wasn't even on the charge because the price was above the shown range.
Tom Randall atBloomberg writes: "The reason solar-power generation will increasingly dominate: it’s a technology, not a fuel. As such, efficiency increases and prices fall as time goes on. The price of Earth’s limited fossil fuels tends to go the other direction." That's a very insightful point. Oil and coal are not technologies. It's possible to make gasoline engines and coal power plants somewhat more efficient, but mostly, we're in linear world; we dig coal out of the ground, we pump oil, over time the easily accessible sources get depleted so we have to go deeper and farther away, it becomes harder.
Solar is different. The sun always shines for free. It's the panels that matter, and these - unlike a fuel - benefit from all kinds of exponential improvements, just like computer electronics. Once a solar panel has been made, it'll produce clean energy for decades without needing to be replaced and without burning any fuel. Capacity is cumulative, and each new panel produced is added to the total of producing panels. This is very much unlike producing oil barrels, for example, and it helps explains why solar will take the world by storm differently than other energy sources did (with an increasingly hard to get supply of fuel had to be secured at huge costs in infrastructure and wars, etc).
You can click on the graphs above to get more details.