From today to 2030, it is estimated that about $7.7 trillion (with a "T") will be invested in energy production around the world, with about half of that amount going to Asia where power needs are growing quickly. The good news is that renewable energy soon won't be "alternative" energy, it'll be the main course; Bloomberg New Energy Finance estimates that over the next 16 years, the world will go from being about 2/3 powered by fossil fuels to over half of the energy coming from zero-emission sources, with renewables making up over 60% of the 5,579GW of new capacity and $5.1 trillion, or about 65% of the $7.7 trillion of new investment.
Asia will account for $2.5 trillion of the total, the Americas $816 billion, Europe $967 billion, and the Middle East and Africa $818 billion.
Here's what this looks like when you put it all together:
If solar power does go from 2% to 18% in 2030, that's 9X as a percentage. But remember, the total amount in 2030 will be significantly bigger, so not only is the slice of the pie larger, but the whole pie is growing too.
Wind power is expected to more than double too, from 5% to 12% in 2030. That's a good performance, but it shows that solar is the energy source with the biggest tailwind (ha!) because of rapidly falling costs, as you can see in the graph below.
Rooftop solar PV is expected do quite well, accounting for around 20% of the capacity additions and investment by 2020.
“The period to 2030 is going to see spectacular growth in solar in this region, with nearly 800 gigawatts of rooftop and utility-scale PV added,” Milo Sjardin, BNEF’s head of Asia Pacific, said. “This will be driven by economics, not subsidies, as our analysis suggests that solar will be fully competitive with other power sources by 2020.”
Pure economics are going to do most of the job as renewables become cheaper and cheaper, but to accelerate things and avoid environmental problems, policy efforts will also be required. Personally, I'd favor cutting susidies to fossil fuels and investing in energy-efficiency, two very big low-hanging fruits that are ripe to be picked.