As a percentage of the current market size, the R&D for batteries and renewables is probably an order of magnitude greater than R&D in fossil fuels.

From a public investment perspective, the trend is that fossil fuel R&D is shrinking, and renewables investment is increasing or steady. Renewables public investment was first higher than fossil fuels in 1998, and has been higher than fossil fuel public investment 9 out of the last 10 years. [1]

[1] - https://www.iea.org/statistics/rdd/

But 20 G$ isn't 100 G$... And that's just for the IEA countries, if you aren't counting the big fossil fuel players like Russia and OPEC on one hand and also China on the other - what is even the point of these numbers ?

And I see that the biggest US tight oil firms had a deficit of nearly 7 G$ for 2018, so I'd assume that their development costs (which are the majority of their costs due to the very high depletion rate) are even higher - so where does yours "order of magnitude greater" comes from ?

https://www.reuters.com/article/usa-shale-finances/cash-flow...