Thursday, July 6, 2017

Decarbonizing with 100% Renewables: A Rallying Cry for Anti-Fossil Fuel Advocates but Reality Stands in the Way



Decarbonizing with 100% Renewables: A Rallying Cry for Anti-Fossil Fuel Advocates but Reality Stands in the Way

Ever since Stanford engineering professor Mark Jacobson did some crude (and quite questionable) modeling in order to show that 100% renewables by 2050 was a technically and economic possibility with current technology in the U.S. this has been put forth as a real possibility but is it? With current technologies the costs would quickly overwhelm the effort. With real renewable energy technology breakthroughs in the next couple of decades it could be a possibility. Even though Jacobson went around proclaiming his plan even on late night talk shows and popularizing it with clean energy advocates some of his numbers have been debunked and he apparently removed some of his data to keep it from further scrutiny. Of course, he responded to his critics. I wonder about his technical accounting – things like cost of redundancies due to intermittency, costs of smart grid deployments, cost of lost peak generation, costs of his massive deployment of storage and hydrogen, distributed energy configurations, costs and logistics of electric transmission projects from windy and sunny hubs, and so much more. Another huge factor would be a total overhaul of the national utility system with cooperation from regional power authorities and multiple state utility regulation commissions. Then there is the overhaul of the transportation system. Every person and business that owns planes, cars, trucks, power equipment, stoves, heaters, furnaces, lawn mowers, garden equipment, agricultural and mining equipment, and on and on – would have to replace that equipment. Basically, anything non-electric would somehow need replaced. That would be a massive undertaking in any kind of short time period. I would not be so skeptical if there was some evidence of that level of transition looming somewhere on the horizon but there does not seem to be at all. He and others talking about climate change often say that all we are lacking is the political will (and perhaps tens or even hundreds of trillions of dollars). The idea at present seems to me more like a rallying cry to condemn fossil fuel projects. Stranded asset over-consideration, the divestment movement, and the ‘Keep it in the Ground’ movement seem to be other maneuvers. Climate change impact consideration is perhaps another but from a more practical and less biased perspective.

Apparently, a group of scientists tried to get Jacobson to correct his errors and implausible assumption and his refusal led to the publishing of a rebuttal paper. The strong and thorough rebuttal by Christopher Clack and 20 other scientists details the problems with Jacobson’s analysis. Jacobson’s response (in the EcoWatch article referenced below) takes issue only with a few of the objections. In his official PNAS response he is more detailed but does not seem convincing. I don’t pretend to understand all the ins and outs of grid balancing and energy storage deployment. No doubt there are yet many technological and logistical bugs to be worked out with such storage deployment and complete overhaul via electrification and hydrogen storage for transport. Robert Bryce’s article referenced below gives context of the prominent scientists involved in the rebuttal and summarizes some of their conclusions:

“In their scathing takedown of Mr. Jacobson, Mr. Clack and his co-authors — who include Carnegie Mellon University professor and former EPA Science Advisory Board chair Granger Morgan, Ken Caldeira of the Carnegie Institution for Science and Jane Long of Lawrence Livermore National Laboratory — concluded that Mr. Jacobson’s 2015 paper contained “numerous shortcomings and errors.” The paper used “invalid modeling tools, contained modeling errors and made implausible and inadequately supported assumptions.” Those errors “render it unreliable as a guide about the likely cost, technical reliability or feasibility of a 100 percent wind, solar, and hydroelectric power system.”

Bryce especially harps on the absurd amount of land required – basically two Californias or 6% of the entire U.S. landmass at average power density of wind turbines at 3 watts per square meter. The Clack etal paper also notes that with massive deployment the power density goes down, not up, as massive deployment actually slows down wind locally (although Jacobson does purport to have taken this competition for kinetic resources by adjacent wind turbines into account). Apparently, Jacobson’s analysis factored in a power density of around 9.4 watts per square meter and thus trimmed the land requirement by a factor of 15! Jacobson states that his data for this comes from a study of 12 European and Australian wind farms.

Jacobson’s EcoWatch rebuttal is perhaps instructive as to his goals. His statement about the paper published by “… by nuclear and fossil fuel supporters, which is replete with false information …” suggests that the prominent scientists who rebutted him are inherently biased against renewables. That is a fairly typical response – immediate demonization of retractors – that gives away the strength of his own bias. He also says, “The paper is dangerous because virtually every sentence in it is inaccurate …” That is another statement that immediately betrays his bias and level of frustration. Even publishing on such a biased media source as EcoWatch betrays his anti-fossil fuel bias. I found Jacobson’s rebuttal to be weak, mainly stating that things like massively scaled-up underground thermal storage, massively increased hydro, and massively increased use of hydrogen (much for air travel) are possible in the next 30 years or so, not particularly feasible. I think he is correct that nuclear and carbon capture and storage are also quite expensive and probably will not be strong bases for economic decarbonization but they will likely have some role. Indeed, in developing countries where future significant coal use is a reality there are many nuclear and CCS projects and much research. 

According to James Conca’s Forbes article referenced below:

“Jacobson has even formed a non-science advocacy group with celebrity board members like Mark Ruffalo, Leonardo DiCaprio and Van Jones, supported by weighty politicians like Bernie Sanders, that have embraced Jacobson’s ideological mix and push it blindly.”

Conca also emphasizes Jacobson’s dissing of the peer review process. Jacobson made the unusually arrogant statement:

There is not a single error in our paper.”

He notes that Jacobson’s work is often the sole source of policy positions of energy extremists and this has been affecting real policy goals in some places:

“Unfortunately, the paper has spawned a horde of state and federal policies which mandate goals that can’t be achieved with available technologies at reasonable prices. This has led to ‘wildly unrealistic expectations’ and ‘massive misallocation of resources,’ according to David Victor, a researcher at the University of California, San Diego, and one of the coauthors of the critique. ‘That is both harmful to the economy, and creates the seeds of a [public] backlash.’”
“Especially against scientists.”

In the developing world the most practical and inexpensive energy systems are necessary to provide the best energy access for human development. Thus, 100% renewables is not even on the radar there nor should it be. Only rich and developed countries or those with vast untapped hydro resources for a small population could vastly increase their share of renewables. European countries like Germany have made strong pushes toward renewables with impressive success but also with new expenses as more intermittent and unreliable generation floods and unfloods the grid. Their greenhouse gas emissions in several cases have not been reduced at all compared to the U.S. which has shown strong reductions primarily due to fracking and subsequent coal to gas switching in power generation. The EV revolution has yet to begin but does seem to be inching closer although it will take time without solid economics and improved capabilities including increased driving range, longer battery life, more infrastructure, faster charging times, and perhaps cheaper battery replacement costs. Volvo’s very recent announcement that all the cars they manufacture will be electric from 2019 onward is verification that the EV revolution is looming, at least for their markets in Europe and China. Their goal is to sell 1 million EVs by 2025. However, these plans also include hybrids and plug-in hybrids so many will still have internal combustion engines – thus the EcoWatch headline is (once again) inaccurate. It is more likely that the 2030’s will see the bulk of the EV revolution.

Bjorn Lomborg’s article, referenced below notes that the EIA concluded in their Annual Energy Outlook for 2017 that renewables would power 16.4% of the U.S. (note: this estimate includes all power, electricity, transport, etc.) by 2050 with then assumed full implementation of Obama’s Clean Power Plan which has been rolled back by Trump. Much of those renewables would still be hydro and biomass which often have environmental issues and still contribute significant carbon in the case of biomass. He roughly estimates that U.S. renewables subsidies from 2010-2050 (presumably at current levels) will total $2 trillion.

The article by Joshua D. Rhodes referenced below seems a fair summary of the debate by one who appears to support the effort. He doubts Jacobson etal’s notion of up to 10 times hydro output capacity is feasible. He notes that Jacobson etal’s assumption of storage methods like underground thermal energy storage (UTES) and phase change materials (PCM) are not mature technologies and are not demonstrably scalable. PCM is mainly combined with concentrated solar thermal (CSP) which currently utilizes natural gas. Jacobson acknowledges that UTES is not an efficient method of electricity storage but prefers it over battery storage for its lower cost. Putting in shallow geothermal systems or UTES in populated areas with dense housing amidst other underground utilities on a massive scale does not seem feasible. Rhodes states:

“I tend to be bullish on the potential of technology to advance rapidly, but having worked in residential energy use, and energy retrofits in particular, I find the amount of geothermal energy storage retrofits for heating and air-conditioning in buildings Jacobson assumed hard to fathom.”

He also offers further doubts:

“I have some reservations on the ability of 67 percent of demand to be flexible. I also have some questions on the pace of investment required in Jacobson’s scenario.”

Regarding the use of UTES, PCM, and hydrogen Clack etal conclude that:

Although both PCM and UTES are promising resources, neither technology has reached the level of technological maturity to be confidently used as the main underpinning technology in a study aiming to show the technical reliability and feasibility of an energy system. The relative immaturity of these technologies cannot be reconciled with the authors’ assertion that the solutions proposed in ref. 11 and companion papers are ready to be implemented today at scale at low cost and that there are no technological or economical hurdles to the proposed system.

The 100% wind, solar, and hydroelectric power system study (11) also makes unsupported assumptions about widespread adoption of hydrogen as an energy carrier, including the conversion of the aviation and steel industries to hydrogen and the ability to store in hydrogen an amount of energy equivalent to more than 1 month of current US electricity consumption. Furthermore, in figure S6 of ref. 11, hydrogen is being produced at a peak rate consuming nearly 2,000 GW of electricity, nearly twice the current US electricity-generating capacity.”

The authors also criticize Jacobson etal’s ‘grid integration modeling’ and characterize his efforts as “insufficient power system modeling.” They note that Jacobson etal did not model or analyze transmission and did not account for frequency regulation requirements, thus the modeling was insufficient and oversimplified. They also note that the modeling did not adequately address the variability and inherent unpredictability of wind and solar generation which often requires significant redundancy to keep the grid balanced.

It should be noted that other studies of ‘deep decarbonization’ have been undertaken and various scenarios put forth. None comes near to the Jacobson, etal conclusions about feasibility and cost and he apparently did not adequately address issues brought up in those other studies, as Clack, etal conclude:

The scenarios of {Jacobson, etal) can, at best, be described as a poorly executed exploration of an interesting hypothesis. The study’s numerous shortcomings and errors render it unreliable as a guide about the likely cost, technical reliability, or feasibility of a 100% wind, solar, and hydroelectric power system. It is one thing to explore the potential use of technologies in a clearly caveated hypothetical analysis; it is quite another to claim that a model using these technologies at an unprecedented scale conclusively shows the feasibility and reliability of the modeled energy system implemented by midcentury.” 

The bottom line here is that the very term ‘100% renewables’ is mainly an overused derogatory catch-phrase of anti-fossil fuel activists and part of their unreasonable, impractical, and obstinate goal of demonizing fossil fuels, lately particularly natural gas and oil. 70% or even 80% renewables is a more reasonable mid to long-term goal. I think the 100% goal just feeds into some sort of mythic narrative of complete victory for decarbonization where those who advocate for it become the heroes. Thus the goal can really be seen as a rallying cry for complete victory with no compromise with the ‘enemy’ and part of a narrative of demonization of fossil fuels. Jacobson’s work legitimizes such a narrative that has been adopted by Sanders, Cuomo, McKibben, the Sierra Club and other fossil fuel despisers. At present 100% renewables is a hypothetical, a thought experiment. While there is some chance it may be technically feasible with some innovation breakthroughs, it is not anyway near economically feasible, let alone logistically feasible or politically feasible. The only way it could even be embarked upon is if massive and wholly unprecedented political agreement was realized.

Economically feasible decarbonization requires a variety of fuel sources. Natural gas has proven to be most effective in replacing coal on electric grids and that will continue as long as gas is cheap but only where there is sufficient infrastructure. Grid penetration of solar and wind will continue to rise. Battery and other energy storage will grow but how much is dependent on cost. Grid integration challenges will be worked out eventually as intermittent sources and distributed sources grow on various grids around the world. The decarbonization analyses in the Grist article by six energy experts referenced below note several different emphases to decarbonize: CCS, mass adoption of EVs, solar and wind, some natural gas, and carbon pricing. One offers a sequence: decarbonize the grid then electrify everything else. This shows that there are quite a few different scenarios.

It should be noted that some of Jacobson etal’s proposals may well be implemented successfully and become quite useful for decarbonization – in some places and if successful, in gradually more scaled-up versions. Coupling cooling, refrigeration, and heating to UTES may prove useful as it has in the district heating in Denmark and in projects in Canada. However, this tech is more applicable to new building and far less applicable to retrofitting. As in many of these schemes upfront capital costs are a barrier to implementation. The use of glycol solutions (antifreeze) could potentially lead to leakage that could contaminate groundwater if such underground storage was massively scaled up. His workflow/protocol for grid balancing could theoretically work (perhaps with better accounting for frequency regulation) but the main issues are upfront capital costs and perhaps massive disruption through massive buildouts. 

The whole idea of running primarily on wind, hydro, and solar is not without merit, especially if evidence of alarmist-level climate change effects becomes apparent. It is a useful engineering problem to tackle and a great thought experiment. However, insisting on 100% renewables and coupling it with anti-fossil fuel propaganda firmly aligns the experiment with specific policy goals rather than a goal applying sound science.

References:

Debunking the Unscientific Fantasy of 100% Renewables – by James Conca, in Forbes, June 26, 2017

How America Can Declare Independence from Dirty Energy – by Grist Staff, in Grist, July 3, 2017

Volvo Announces ‘Historic’ End to Combustion Engine, All Cars Going Electric – by Lorraine Chow, in EcoWatch, July 5, 2017

No, Renewables Won’t Power the U.S. Soon – by Bjorn Lomborg, in LinkedIn (Oil & Energy), July 4, 2017

The Appalling Delusion of One Hundred Percent Renewables – by Robert Bryce, in Pittsburgh Post Gazette, July 5, 2017

4 Reasons Nuclear and Fossil Fuel Supporters Criticizing 100% Renewable Energy Plan Are Wrong – by Mark Jacobson, in EcoWatch, June 19, 2017

Evaluation of a Proposal for Reliable Low-Cost Grid Power with 100% Wind, Water, and Solar – by Christopher T. M. Clack, Staffan A. Qvist, Jay Apt, Morgan Bazilian, Adam R. Brandt, Ken Caldeira, Steven J. Davis, Victor Diakov, Mark A. Handschy, Paul D. H. Hines, Paulina Jaramillo, Daniel M. Kammen, Jane C. S. Long, M. Granger Morgan, Adam Reed, Varun Sivaram, James Sweeney, George R. Tynan, David G. Victor, John P. Weyant, and Jay F. Whitacre, in Proceedings of the National Academy of Sciences (PNAS), June 19, 2017

Energy Wonks Have a Meltdown Over U.S. Going 100% Renewable – Why? – by Joshua D. Rhodes, in Green Biz, July 3, 2017

The United States Can Keep the Grid Stable at Low Cost with 100% Clean, Renewable Energy in All Sectors Despite Inaccurate Claims – by Mark Z. Jacobson, Mark A. Delucchi, Mary A. Cameron, and Bethany A. Frew, in Proceedings of the National Academy of Sciences (PNAS), June, 2017

Low-cost solution to the grid reliability problem with 100% penetration of intermittent wind, water, and solar for all purposes - by Mark Z. Jacobson, Mark A. Delucchi, Mary A. Cameron, ,and Bethany A. Frew, in Proceedings of the National Academy of Sciences, Nov. 2 2015

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