Fighting global warming and climate change requires a broad energy portfolio

June 19, 2017
This map shows wind resources across the contiguous United States at 80 meters above ground level. The team's research says that this resource is variable, so a broad portfolio of other technologies is needed to move to a zero-emissions energy future. Credit: Christopher Clack and Vibrant Clean Energy LLC.

Can the continental United States make a rapid, reliable and low-cost transition to an energy system that relies almost exclusively on wind, solar and hydroelectric power? While there is growing excitement for this vision, a new study in the Proceedings of the National Academy of Sciences (PNAS) by 21 of the nation's leading energy experts, including David G. Victor and George R. Tynan from the University of California San Diego, describes a more complicated reality. These researchers argue that achieving net-zero carbon emissions requires the incorporation of a much broader suite of energy sources and approaches.

The paper published by PNAS the week of June 19, 2017, with Christopher Clack as first author, provides a rigorous analysis that corrects a 2015 research roadmap indicating that the continental United States could be reliably powered at low cost, in as little as 35 to 40 years, relying on just solar, wind, and hydroelectric power. The researchers write that the conclusions in the 2015 paper are not supported by adequate and realistic analysis and do not provide a reliable guide to whether and at what cost such a transition might be achieved.

"Wind, solar and hydroelectric power can, and will, be important parts of any moves to decarbonize our energy system and therefore combat climate change, but given today's technical challenges and infrastructure realities, renewables won't be the only solution," said Victor, an energy expert at the UC San Diego School of Global Policy and Strategy. Victor and fellow co-author Tynan, who is associate dean of the UC San Diego Jacobs School of Engineering, are co-directors of the Deep Decarbonization Initiative at UC San Diego, which they launched to tackle the interrelated policy and technology challenges that must be addressed to get to zero global carbon emissions.

"We need a broad portfolio of clean energy technologies in order to achieve an affordable transition to a low-carbon-emission energy system," said Tynan, a professor in the Department of Mechanical and Aerospace Engineering at the Jacobs School and a member of the UC San Diego Center for Energy Research.

The new work references a number of analyses, meta-analyses and assessments, including those performed by the Intergovernmental Panel on Climate Change, the National Oceanic and Atmospheric Administration, the National Renewable Energy Laboratory, and the International Energy Agency, that have concluded that deployment of a diverse portfolio of clean energy technologies makes a transition to a low-carbon-emission energy system both more feasible and less costly than other pathways.

"A policy prescription that overpromises on the benefits of relying on a narrower portfolio of technologies options could be counterproductive, seriously impeding the move to a cost effective decarbonized energy system," the authors write in the PNAS paper.

This discussion is particularly timely because proposals for rapid shifts to all or nearly all renewables are gaining increased attention from policy makers, politicians and the general public.

"Getting to 80 percent reduction in carbon emission rates is going to be tough, and decarbonizing beyond 80 percent will be even more challenging. That's why it's important to be as rigorous as possible in laying out a pathway to this goal," Tynan said.

"When we talk about reducing the amount of carbon in the atmosphere—decarbonization—there is an increased recognition that a diversity of approaches is not only smart, but necessary," said Victor, who is also co-director of the Laboratory for International Law and Regulation at UC San Diego and co-chairs the Energy Security and Climate Initiative at the Brookings Institution.

This kind of broad energy portfolio is likely to include bioenergy, wind, solar, hydroelectric, nuclear energy and carbon capture, the authors say.

"We are focused on helping governments, communities, companies and societies cut emissions of warming gases given the very real technological, economic and political constraints that exist," Tynan said. "It's important for policy makers and the public to understand we still have significant progress to make before we are have a realistic chance of achieving the required emissions reductions reliably and cost effectively."

For the PNAS study, the authors identify many technical challenges to moving toward an energy system built solely on wind, solar and hydroelectric power.

The authors also argue for deploying new technologies and innovation, such as cutting-edge energy storage and new control systems. With experience, they say, a much greater role for renewable energy may be feasible.

"Ultimately we're talking about getting to zero—getting our global carbon emissions to levels that will combat climate change immediately. This is deep decarbonization in the real world, cutting global emissions at scale while still meeting the energy needs of a growing, global population," said Victor.

Explore further: Renewable energy – not always sustainable

More information: Christopher T. M. Clack el al., "Evaluation of a proposal for reliable low-cost grid power with 100% wind, water, and solar," PNAS (2017). www.pnas.org/cgi/doi/10.1073/pnas.1610381114

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aksdad
3.2 / 5 (9) Jun 19, 2017
It's good to see the occasional reality check on the unrealistic pronouncements of the climate change doomsayers. Let's take it a step further and start asking why anyone needs to "combat climate change". Humans can't even control extreme weather like tornadoes and hurricanes which are minuscule problems compared to global climate change. Are we going to change the wobble, tilt and movement of the earth around the sun to minimize the climate effects of Milankovitch cycles? They have a much greater effect on global climate than do human CO2 emissions. In fact the signature of human CO2 emissions on warming is so small that it is virtually undetectable amid natural variations.

How about we do what our prehistoric ancestors did so well and simply adapt to the effects of climate change; effects which for the foreseeable future will occur so slowly that they are virtually unnoticeable.
Dingbone
Jun 19, 2017
This comment has been removed by a moderator.
rderkis
2 / 5 (1) Jun 19, 2017
Lets just get to fusion and be done with it. Fusion is just around the corner literally. We have worked on fusion for decades and now it is within our grasp. All it would take is one good push, using MIT's technology, which is pretty much the same as ITERs. MIT uses REBCO superconducting lines which can make the field strength almost twice what ITER produces. That allows a 10 fold reduction in size of reactor. Which translates to VARY greatly reduced cost.
Lets just get to fusion and be done with it!
BackBurner
3.3 / 5 (7) Jun 19, 2017
"Can the continental United States make a rapid, reliable and low-cost transition to an energy system that relies almost exclusively on wind, solar and hydroelectric power?"

No. Next question?
24volts
5 / 5 (4) Jun 19, 2017
It's possible but it's going to take a lot more interconnections and storage systems. I'm not all that sure with today's political environment that would be a good thing though. Having a system that would fail over the entire country if something happened would not be a good end result. I
think various systems would have to be able to isolate in that instance so it's going to be a very complicated power system to keep running properly.
omegatalon
1 / 5 (1) Jun 19, 2017
We're going to need to think outside the box with things like solar arrays over a mile in diameter in geosynchronous orbit to convert solar energy to electricity then beam that power to a ground station.
greenonions1
4 / 5 (8) Jun 19, 2017
No. Next question?
As usual - very complex response. Actually there are many studies that show that converting to renewables is feasible. The time line is a big question. Are we talking 10 years, or 100 years? As wind and solar continue to drop in price - the transition will probably accelerate. The economics are very interesting. Nukes here in the U.S. are clearly not economically viable. Look at Vogtle - http://www.theene...complete The Russians are doing a lot around the world with nukes - so it is interesting to see if they can bring the numbers into a better range. Seems not. Here are the numbers on the new Turkish plant that is in design. http://www.theene...rly-2018 Capitol cost of $4,600 per Kw, or $4.6 per watt. That is before thinking about operating costs. Cont.
greenonions1
4.3 / 5 (6) Jun 19, 2017
cont Utility scale solar is coming in around $1.40 per watt. http://www.nrel.g...7142.pdf Adjusting for the capacity factor 15 - 35% http://www.powerm...-design/ so shoot for the mid point of 25% - you see that solar is currently almost as cheap to install, and in the right locations (most of soutwest) is as cheap. Once installed - the solar has very little operating cost - compared of course to a nuke - and no waste to baby sit for thousands of years. The big factor is looking at the cost curve on both wind and solar. By the time a nuke got built (say around 6 years) solar and wind are going to be hands down the cheapest.
greenonions1
4 / 5 (4) Jun 19, 2017
omegatalon - do you have any cost estimates on such a system? This article suggests that to be cost competitive with current power - the cost to launch a Kilogram into space needs to be around $400 http://discoverma...r-energy Space X is still talking around $9,000 per pound - http://www.busine...t-2016-6 So it would seem that we are better working with earth based systems for the foreseeable future.
Caliban
3.2 / 5 (5) Jun 19, 2017
Corporatist policy wonks without any real grasp of even current tech(current authors) VS corporatist policy wonks advocating a naked power grab(previous writers).

As always, these clowns are advocating for highly resource-intensive alternatives that will be funded by PUBLIC investment, and then turned over to for-profit corporate interests.

contd

Additionally, these twats call for a bunch of waste spending on non-starters like hydro, nuke, and biofuel, all of which create environmental damage and down-stream pollution effects, and, just as with pumped storage, require massive energy to to keep operating(nuke less so).

Everyone knows that these kinds of epicyclic power generation schemes are horribly inefficient and wasteful, and yet here we have supposedly eminent, credible scientists advocating for them.

Caliban
3 / 5 (4) Jun 19, 2017
There are currently a number of viable storage technologies for any and all generated electricity -just from what has been published here on PORG- all that is required is the political will to begin planning and deployment, along with continuing R&D and retrofitting as the tech advances.

This is the only sane, safe way forward, until or unless some breakthrough with fusion or other miraculous energy from nothing principle is discovered.
MR166
4 / 5 (4) Jun 19, 2017
"There are currently a number of viable storage technologies for any and all generated electricity"

I suppose one would have to define "Viable" in order to evaluate the statement. I do not see private industry installing battery banks to store megawatts of renewable. It will happen sometime but it is not ripe yet. It will be interesting to see what Musk is able to accomplish.
PTTG
4.1 / 5 (9) Jun 19, 2017
If one blocks a small number of posters, then a pattern quickly emerges: It's always the same few posters who immediately respond to anything vaugely solar or climate-change related, and they're all denialists.

It's so consistent and universal that it leads me to one of two conclusions: either they have no jobs and no life, or it _is_ their job.
rderkis
1 / 5 (3) Jun 19, 2017
t's so consistent and universal that it leads me to one of two conclusions: either they have no jobs and no life, or it _is_ their job.


Since you have been here enough to notice it makes me wonder which of these categories you fit in.?
BTW Just to help you with the higher math that 3 conclusions not 2.
ddaye
3 / 5 (2) Jun 19, 2017
The discussion is moot because the US political leadership opposes government involvement in these and most matters. And there isn't a major political movement or party that favors empowering government enough to transform the economy.
Troll_Terminator
2.6 / 5 (8) Jun 19, 2017
Most of the world's enviro problems stems from the public's seeming inability to control, cease and desist their polluting of our waterways, seas, oceans, and forgetting to recycle steel and aluminum containers, plastics, paper and cardboard, and other items which are dumped into landfills with no care of current and future impacts on our home planet. Their attitude (dumb!) is to let the other guy worry about it. Too many humans have that dumbass attitude, which is why our air and water is becoming more and more polluted and filthy with the passing years. When it all begins to affect their own personal health, they will scream about "climate change" and "global warming" instead of cleaning up their own szhitt like they should've been doing all along
greenonions1
3.8 / 5 (4) Jun 19, 2017
MR says
I do not see private industry installing battery banks to store megawatts of renewable.
https://www.pv-ma...-system/
rderkis
1 / 5 (2) Jun 20, 2017
Too many humans have that dumbass attitude


Says the man who drives his car everywhere.
vacuumforce
1 / 5 (2) Jun 20, 2017
Humans aren't responsible for global warming.

The earth is just bipolar.
rderkis
1 / 5 (2) Jun 20, 2017
Humans aren't responsible for global warming.

The earth is just bipolar.

:-)
antialias_physorg
5 / 5 (4) Jun 20, 2017
It's possible but it's going to take a lot more interconnections and storage systems.

No one is denying that. The point is that there are several steps and they have to betaken insequence
1) Generation by renewables
2) Once 1) is well under way connection of renewables
3) Once 1) and 2) are well under way: Storage
Any other sequence makes no sense.

The countries that are switching over are - at best - currently in stage 2)

Those that scream about 'not feasible', 'intermittent' and whatnot don't seem to realize the magnitude of the task and the timeline involved (as well as the economics of it). The senible changeover - which countries are embarking on - is one that takes each step when it's appropriate and most effective.

"Can the continental United States make a rapid, reliable and low-cost transition to an energy system that relies almost exclusively on wind, solar and hydroelectric power?"

Yes. Just be replacing old powerplants as they wear out.
Old_C_Code
1 / 5 (2) Jun 20, 2017
Don't ignore SAFE Thorium molten salt FISSION reactors, because of the word fission. Proven viable sixty years ago. Using Thorium creates no waste to make weapons, so it was not used.
MR166
5 / 5 (1) Jun 20, 2017
Thanks for the very interesting link Onions. Do you have any idea how much it will cost to deliver a KWH over it's expected lifetime? BTW I am very happy that this is now possible just as long as the true costs are reasonable.
MR166
3 / 5 (2) Jun 20, 2017
"Don't ignore SAFE Thorium molten salt FISSION reactors, because of the word fission. Proven viable sixty years ago. Using Thorium creates no waste to make weapons, so it was not used."

Yes, it is a mystery that these are not being developed. Are there some sort of problems that have not been overcome yet?
antialias_physorg
5 / 5 (3) Jun 20, 2017
Don't ignore SAFE Thorium molten salt FISSION reactors, because of the word fission.

They aren't production ready (particularly the salt cooling cycle isn't safe at regular operation - much less so if compromised during something like an earthquake or a tsunami.)

In any case: until these are production ready and built in any appreciable numbers we're talking many decades (you need to set up companies and train people and build factories for the parts and search for sites and build these things...all of which after a few prototypes have been built and run and refined over a decade or so). Looking at that kind of timeline renewables will have long done the job - at a much lower price.
greenonions1
5 / 5 (4) Jun 20, 2017
MR - here is a quote from Macron - leader of the country in the world that gets most of it's power from nukes.
Nobody knows the total cost for nuclear energy. I was minister for industry and I could not tell you
https://energytra...eriment/ What we can tell you is that the British government had to guarantee EDF 12 cents Kwh (adjusted up for inflation) - to build Hinkley Point. The Turkish capitol costs are coming in lower - $4.6 per watt vs $9.4 per watt. The operating costs are the tough ones to nail down. And what about decommissioning? Nukes are famous for going way over budget - so the final numbers may be years away.

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