You don't need private investment to do electrification and renewable energy. That can be done by the government. Which doesn't have funding problems, ever.
You absolutely still need private investment in a growing economy to produce and invent these technologies.
What the government incentives then can do is speed up their rates of adoption and installation. But you need both sides -- public and private.
The whole history the twentieth century is the evidence that such a system doesn't work. And it especially doesn't work as technology has become increasingly complex.
Markets are vastly better-informed investors than governments can ever be. Which is why it's generally vastly better for governments to skew incentives for private investment to favor a particular area, rather than make investments directly.
The reason this is not a good trend is that the KIND of R&D businesses do vs government are very different. Government invests in basic research and invention while business invests in innovation.
Less money is going into science and more into squeezing money out of people via innovation. I would argue this is because the sector that makes all the important decisions is now the FIRE sector, which only thinks about the next quarter.
source: https://ncses.nsf.gov/data-collections/national-patterns/202...
The government doesn't need the private sector, it allows the private sector to exist where it's deemed beneficial.
You may also ask Argentine.