Those who look at the small fraction of world energy generated by renewable sources and think that it will be a long time before fossil fuels will be a very small part of the energy mix are guilty of linear thinking. Such thinking makes sense in the short run or when there is no reason to expect exponential growth, but that’s not how we should look at renewable energy trends.
In the last 7 years increases in wind energy capacity world wide have grown by an average of over 20%, https://en.wikipedia.org/wiki/World_energy_consumption#Renewable_energy, and the growth rate for solar energy capacity has been even higher. If you were lucky enough to get 20% on a financial investment per year, your money would double in just under 4 years. In 20 years you would have nearly 40 times your initial investment. In 30 years you would have nearly 240 times your initial investment!
This is what can happen with renewable energy if the world maintains current increases in investment rates.
When I point this out most people dismiss the numbers because they don’t think such increases are sustainable. That’s also partly due to linear thinking and partly due to not considering that investments not made in fossil fuels can be investments made in renewable energy systems.
The linear thinking part misses the fact that costs per installed capacity for wind and solar systems are dropping and are likely to continue to do so.
At the same time energy storage costs are also dropping.
Investments in electric cars are also driving improvements in battery technologies and reductions in costs.
This might be a bit optimistic, but if the world takes the greenhouse gas problem seriously, it will be possible to get just about carbon neutral in at most 30 years. With real seriousness of purpose this could be done in 20 years! Also this can happen with no economic disruption.
To put these trends in perspective, in about 2010 I predicted that gas powered cars would be on the way out by 2020 and be a small part of the business by 2025. That seemed laughable at the time to most people, but Joe Romm’s article suggests that this timetable is reasonable.
It is amazing what can be done with continuous drive.