Certain green technology derived products are shifting towards the "early adopter" phase of development. They are by no means mainstream yet and are not able to finance themselves. They depend on long term investments that do not provide a short term positive return. Hydrocarbon driven technologies however are in the mainstream phase, or even already beyond that. The hydrocarbon related industry attracts sufficient investments itself to be able to sustain it's own position. Because (at least according to my opinion) there is insufficient diversity within our energy supply, the major part of investments in the energy supply chain of a normal risk level do end up in he hydrocarbon area. To call it a black hole would a bit to demagogue, but it's not that far of. Hydrocarbon related industries do have a lot of (political) power and are very capable of sustaining their own interests, making developments towards sufficient diversity within the energy supply chain very difficult.Let me clarify my previous answer. I'm not entirely against research subsidies for green technologies.
The problem however is that it's looking more like those subsidies will continue indefinitely.
This is a classical example of a situation were government regulation is required.