That seems like a simple calculation to solve, no? The government has the capacity to fund specific technological advances. They've done it in the past, so they can certainly do it now. There's no guarantee that investment in fusion research will yield timely results (I looked up a Forbes thing and it said there's the distant hope of having a commercially viable reactor by 2050, so that's 30 years out), so enacting energy policy based on a distant maybe feels unwise.
Is the impact on the environment worse if we switch from dirty nonrenewable energy to still-dirty-but-renewable energy? Thus far the consensus seems to be no, unless I've missed something about the production cycle of solar panels and turbines. Still destructive, but immensely better in the long run than fracking, drilling, and burning.
But also important is that efficiency of renewable energy is actively improving year by year. It's getting cheaper to produce, as well. Even if you believe in the economic wonders of coal, it's starting to become more expensive than renewable energy in many places.
Specific investment in fusion energy will likely speed up that expectation, assuming the theory is sound, but specific investment in solar/wind will also immediately remove a major source of pollutants and drive costs down of energy production (to an extent, you'll never wrest the reins of profit-building from the utilities). If we keep the 2050 target for viable fusion reactors that can be safely built and utilized for mass production, that means we have 30 years in front of us that need a definitive answer to the environmental and finite resource quandary. And then probably a decade or more after that to transition from that source of energy to fusion.
We know that oil and coal are finite resources, that they're dirty, and that they pose a definitive threat to our climate and economic future. We can't use them forever, even if you don't care about the environment. And we've already proven that the longer you wait to make a change, the worse the results are, and the harder it is to undo the damage.
So you ask: "What can we switch to, right now, that is better for us in the long term?"
To me the answer is a plain and simple, "Start switching as much as you can to renewable energy sources like solar and wind. Specifically invest in alternative renewable energy research that is more productive and less destructive of the environment."
We're at the stage where top-level changes need to be made five years ago, so we can hardly afford to twiddle our thumbs for ~30 years until something better than solar/wind comes by. The cards we've been dealt say that what we have right now is bad and needs to change, that every moment we dawdle is a moment that causes potentially irreparable long-term consequences, and we know that the best solution is one completely and objectively totally inaccessible for now. So the next best thing is what coal/oil hawks are trying so hard to prevent.
) because they are great but (imo) only as support untill we get to fusion. Worst thing about renewables though is that they take huge amount of space. I agree with that. To build solar/wind farms we still need steel and we still need space which might imply deforestation, draining swams etc. ruining natural habitats for many animals. Frankly nuclear seems most efficient as of now. Maybe as we (if ever) get to fusion it would be easier and cheaper to refit fission reactors to fusion ones if we start building them now replacing that horrible coal plants.
