Of course. But will also be way too late by then for reasons not relating to the economics of it. That's the whole problem.
By what account? It's already too late, the temperature will be rising for the next 100 years minimum. At this point, we need to start developing ways to harvest carbon out of the atmosphere to actually dent man-made climate change. (A technology currently in development btw)
Everyone here is acting like the environment should be saved at all costs, economics be damned, but it's not that easy. Energy is a trillion dollar industry globally, literally every country is tied to it. By making drastic changes to that system without regard for future impact to the global economy is rash. What would be better? a 2100 where we have 5% unemployment, a continuously growing economy, and great benefits for all American workers, where the temperature is 5*C higher than it was in 1990, or one where we are in the greatest depression this country has ever seen, rampant unemployment, a debt which can't be sustained by our GDP a la Greece, and a temperature 4*C higher than it was in 1990?
My argument is fundamentally that economics over time bears for the greater good of mankind despite there being plenty of instances where it fails us in the short term. Global warming needs to be a long play here. I might be on a different side of this argument if I thought we'd be burning coal at the same rate we are now in 100 years, but that's not what's going to happen. Energy companies deal in the billions of dollars, the very second someone figures out how to stay profitable and be able to undercut the cost of fossil fuels, they will make a fortune. That's why there's already an arms race in the energy field, one every company involved in the power industry is already taking a part in. We'll be adapting to renewable energy soon, as soon as the market can bear it, and it will ultimately benefit us, despite the transition taking 10 years longer than many impatient people want.
Look, there are times the government should put money into certain systems which benefit everyone long term which no private company would have a vested stake in. The obvious example is roads and highways: Great for all industries, no one industry would fund it. There are others: the space program, fundamental research grants, police and fire, etc. But all of those have a very important common thread: There is little incentive in the private market for them. That isn't true at all in this case: The private industry is highly incentivized to solve this issue, there's great profit in it. We don't need to add money to research, that money is already available and very plentiful. I also think substantial taxes on fossil fuels (which I think is the angle KI has been getting at) is a terrible plan, as it would reduce the cost of fossil fuels to competitors overseas, and artificially raise the cost of production across all industries here. We aren't in a 1995 economy, our unemployment is low, but wages are stuck. People are still widely under-employed. I don't think our market would bear a volatile shakeup well, companies have been incredibly skittish in their hiring practices over things like the civil war in Syria which should have little affect over energy supply and our market.
EDIT
@KI4MVP
And my point is that the climate issues should give us incentive as a society to expedite the time table of making it cost effective to switch.
If it is going to continue to follow exponential growth, which is expected, investing more resources to accelerate that growth rate has exponential returns on both the investment and the environment.
This is vague, I'll be honest I still don't understand your point. I'll look at 4 ways this could be interpreted, tell me if I'm still missing it.
1. We could fund research in the field. - I would vehemently argue that any additional funding would make little, if any, impact in process development. The technology is following Moore's Law currently, and that's because we already understand how to make things more efficient, we just need to continue to refine and develop the system each year. More money doesn't speed up the process, we couldn't invent a 4.8kHz processor in 1990 with more funding, we just needed time. That is true here as well: For solar panels to become more efficient and cost effective they need more time to develop.
2. We could further subsidize the industry- We are already subsidizing solar at a high level, and I'm not sure what returns we're seeing from that. We're pouring millions of tax dollars into an industry that even with that extra money isn't yet competitive. Each tax dollar spent in this way isn't going towards our debt which would reduce our long term interest rates, and it's not staying in tax payer's hands, which would circle back into the economy. It is being used to buoy a system that, as of now, can't quite stand on it's own.
3. We can increase taxes on fossil fuels- By doing this, we increase the cost of energy nationwide, which affects every industry. If we did it to the point of driving those industries out of business to create a vacuum renewable energy could enter into, we'd cause massive job loss, reduce the cost of raw materials to international competitors, and run a more inefficient system nationally than most of the rest of the developed world for the next 10 years.
4. Build an infrastructure for installing solar energy- No one wants that infrastructure yet, and there's not even a consensus on how to install it. Is the long game that everyone has their own solar panels? Are we going to transition into a DC home system? Who bears that cost, is the government going to come rewire my house for me, or am I going to be expected to put 10k into it? Think of highways and roadways. Cars in the 1920s largely traveled on graveled or brick roads. Had we decided to implore a highway system then to get ahead of our competitors, we'd have built a much more expensive network with a product that would soon be considered inferior to advancements in asphalt production. I'd argue the same is true here: The solar panels today are not the solar panels of tomorrow. We should wait to install the cheaper, more efficient panels which are coming down the pipeline. And the best part about that? The government won't need to buy them. Lincoln Electric will buy them, GE will buy them, Edison will buy them. Or you'll go out and buy them and maintain them yourself, all because it will be cost effective for everyone to do so.