Okay. I'll make this very simple, but it needs an enormous amount of flesh.
I know U.S. numbers and the U.S. is about 15 - 20% of the problem globally, so it's a good example. There are three technology groups which are imperative for a climate solution. Efficiency, wind and solar. With them, everything else matters. Without them, nothing matters. The reason is simply that efficiency, wind and solar can provide 100% of the renewable electricity we need to displace all fossil fuels, and they are cheap enough to do so while also lowering the cost of electricity (and paying for the modest amount of storage we actually need, as opposed to the enormous amounts many other people have claimed incorrectly).
If we build about 60,000 MW's of wind, and 36,000 MW's of solar every year, in about ten years we will have a 100% renewable grid, unless we choose to keep some of the natural gas plants going, and use some of the new renewable electricity to fuel cars, air-to-air heat pumps, and a host of other resources which will replace all the more obscure uses for fossil fuels.
If we continue to build that much wind and solar, in 20 years we will have about 160% of today's electricity, which will provide power to replace most of the aging nuclear plants, replace gasoline, and replace most of the easier diesel vehicles. We will also be able to replace furnaces with heat pumps and natural gas used to make ammonia fertilizer with hydrogen from renewable electricity. What is different about all of this is that three years ago we couldn't have claimed that doing this would save money across the board. Today we can. Wind and solar at three cents per KWh produce hydrogen which is about the same price as current wholesale gasoline. Today we have contracts for wind and solar under 2 cents. When the wind tax credit is gone at the end of this year, wind will still be less than half the cost of fossil, nuclear and natural gas generation in many places, and less than some of it everywhere. By the time we build enough of it to capture all the current opportunities to reduce costs, wind and solar will be even cheaper, and fossil and nuclear fuels will probably be more expensive.
It's a shame that at this point we still have to spend a sentence pointing out that nuclear power is insanely expensive and cannot be deployed fast enough to matter, but we do. We also can expect to keep most of the existing hydropower, geothermal and biomass generation, but very little additional will be competitive with wind and solar. Storage is already cheap enough to make this vision happen. We haven't reached the point where a market signal for storage exists. That probably won't happen until we have about 40% of our electricity from either wind or solar, and storage is already being built for other purposes. There are a number of storage technologies which aren't household concepts the way batteries are, which will be in the running for real deployment.
I want to mention my pet theory, which is that with electricity at 2 - 3 cents per KWh in most of the world, we are likely to build enough wind and solar to produce a significant amount of electricity above consumption. There will be a healthy "dispatchable load" market for discounted power that is sold when it is available. One of the uses, one which could shape all the others, is making hydrogen to store in existing natural gas storage facilities, to use in existing natural gas plants (with modifications) as storage. It also preserves some value in some natural gas plants which might otherwise be unable to recover a healthy return after repaying their original cost.
The 60,000 MW's of wind and 36,000 MW's of solar could easily be 50,000 of each, if solar becomes cheaper than wind per KWh. Unless solar becomes so much cheaper than wind that solar plus storage is cheaper than wind, I doubt that the mix will be much less than 50/50, with the remaining hydro/biomass/geothermal mix. In any case, I'm not trying to promote any particular mix. Just to define a scenario which permits us to consider the requirements seriously.
The 160% of today's generation by 2040 (if we start next year) gets U.S. total greenhouse emissions down 70%. The remaining 30% depends a little on alternative refrigerants, but those could be made easier with abundant cheap electricity, and the remaining emissions are likely to have solutions also made easier with abundant cheap electricity.
This strategy is the solution to rural poverty in the United States, and in the rest of the world. I'm not going to spell that out here, but the economic benefits to rural communities is an astonishingly important part of this, given how little attention it has received.
The ratios of electricity to other fossil fuels will differ somewhat in other countries. The places where this approach is easier in the United States far outnumber the places where it is harder, in size and total energy requirements.
This quite literally poses an economic boom unlike anything our world has seen since the 1950's and 60's in the West.
I'm more experienced with efficiency than with renewables. Efficiency is awesomely simple to promote. Give the utilities a share of the verified savings, equal to slightly more than they make in rate of return. Give it in net present value the year following evaluation, which must be done and you wind up saving $6 - 10 for every dollar spent. The incentive not only gets it done, it also gives the utility a clear economic signal to make its programs run well. This has been well understood by a tiny handful of experts for quite a long time, but for some reason we can't break into mainstream awareness. Our current programs save about $30 billion per year, and we could double that in a matter of months if we mandated the incentives overnight. More likely, some Federal policy would help, but the regulatory work needs to be done in each state.
Renewables may not need any further incentive, now that they are so cheap. What they absolutely need is confidence in market stability, which is what the Federal tax credits provide. If I were calling the shots I would preserve the existing tax credits (the wind tax credit in 2019 is 40% of what it was in 2015) until the renewable energy goal is met. The numbers I give for wind and solar are intended to produce 5.5 GWh's of new generation per year at the actual rate of generation realized by these technologies in 2018. We might need less, or want more.
I don't think we need much else. Existing fossil and nuclear industries are either going to jump on the bandwagon, or fade away, as they choose. Attention to retraining and local economic impacts is appropriate, but not bailouts and golden parachutes.
Government officials tend to want to deal with these issues without understanding the economics. We need to reinforce the factual issues of the lower cost of efficiency, wind and solar by learning them ourselves, and learning how to reinforce eachother as we tell people that this sustainable future is a wonderful place.
I spent a lot of time in the last couple of years talking about conveying a vision of a successful climate response. It's still a valid concept, and perhaps the real need.
I suppose I also need to point out that my vision depends on utility scale solar because rooftop solar is not competitive with wholesale fossil or nuclear generation. But the fact is that a lot of people are building and installing rooftop solar, 30% of total U.S. solar, and probably a similar fraction or larger on a global basis.
This is pretty close to the path of least economic resistance, and that is what is working today. It costs a fraction of the cost of any perceived carbon tax policy. It costs substantially less than what we are doing today on a per KWh basis. It doesn't solve all the climate problems, but it makes solving the other parts worthwhile.
I figure that if a couple of hundred people agreed on something like this vision we could make it happen. In the U.S. it represents about five times as much wind as we are building right now, and about seven times as much solar, but only three times as much wind as we built in 2012, which is our peak year, and only about five times as much solar as we built in 2016. Efficiency is already eliminating about 1.7% of total U.S. electricity with new efficiency installed every year, and we could increase that by at least 1% as I described with incentives. That would bring 44 states up to the efficiency program level of the best six states.
The entire proposal is less than the rate of new coal that the U.S. built for thirty years from 1940 to 1970, and less than China built new coal for about 15 of the last 20 years. And it divides that rate among three technology groups, not just one. It is feasible in a way which no other concept I've ever seen is.
Carbon taxes and cap and trade laws would help, but they create diversionary perceptions and issues. Such as people giving up entertainment and health care to pay a little more for fossil fuels. Or uneconomic decisions made to comply with a cap. Or misrepresentations such as fragile and impermanent biosequestration being used to justify continued fossil fuel use.
Anyways, I'll be eager to see how others see this.