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Some Short Notes on the US-China Climate Deal

The US-China climate deal announced in December 2014 generated big news.  It was yet another diplomatic success for the Obama administration and John Kerry’s State Department.  Nothing I say below takes away from that success.  In terms of climate action success, the deal ranks pretty low to me.  I’ll quickly summarize what I understand of the deal and then share why I think it isn’t a significant climate deal.

The Deal

Here is a quick summary (emphasis mine):

China, the world’s biggest emitter of greenhouse gases, pledged in the far-reaching agreement to cap its rapidly growing carbon emissions by 2030, or earlier if possible. It also set an ambitious goal of increasing the share of non-fossil fuels to 20 percent of its energy mix by 2030.

Obama announced a target to cut U.S. emissions 26 to 28 percent below 2005 levels by 2025 – eight years after he leaves office — the first time the president has set a goal beyond the existing 17 percent target by 2020.

The bolded portions highlight the agreement’s big news.  China agreed to a carbon emissions cap and the U.S. pushed its emissions reduction target out 5 years and increased the target by ~11% below 2005 levels.

Those are good goals.  Are they sufficient goals?  It depends on what you consider sufficient.  I consider goals that will actually achieve the stated climate target of <2C warming by 2100 as sufficient.  These goals won’t achieve that target.  But then, as I’ve written for some time now, I don’t think we can set goals that achieve the <2C by 2100 target.  There are technical and political hurdles that we chose not to surmount during the past 30+ years.  Why won’t this agreement achieve that target?  Let’s take a quick look from the same International Business Times article:

China completes a new coal plant every eight to 10 days, and while its economic growth has slowed, it is still expanding at a brisk rate exceeding 7 percent.

The scale of construction for China to meet its goals is huge even by Chinese standards. It must add 800 to 1,000 gigawatts of nuclear, wind, solar and other zero-emission generation capacity by 2030 — more than all the coal-fired power plants that exist in China today and close to the total electricity generation capacity in the United States.

And to meet its target, the United States will need to double the pace of carbon pollution reduction from 1.2 percent per year on average from 2005 to 2020 to 2.3 to 2.8 percent per year between 2020 and 2025.

Who out there truly believes that China can deploy 800 GW of zero-emission generation capacity in less than 15 years?  Remember before you answer in the affirmative that China’s deployment of coal-fired plants exceeded anything in history and that coal remains an extremely cheap energy resource.  All the other technologies currently cost more in terms of deployment.  What incentives does China, as a developing nation, have to spend more money for intermittent power sources?  They’re more interested in growing their economy, as the U.S. is.  Speaking of the U.S. – I emphasized part of that quote quite purposefully to highlight the scale of the issue.  China must, in 15 years, deploy as much generation infrastructure as exists in the entire U.S. today.  Our infrastructure took decades and decades to build out.  China needs to do the same thing, with more expensive infrastructure, in 15 short years!?  I will be among the first to congratulate China if they accomplish this daunting task and I don’t think China should shy away from working towards it.  I just don’t think they have a realistic chance of actually accomplishing it.

What about the U.S.?  We need to more than double the decarbonization rate of our economy to achieve our emissions goals.  Remember that most of the decarbonization achieved since 2005 was due first to the Great Recession and second to the natural gas boom.  The Great Recession is finally behind us, though effects linger.  The natural gas boom?  It’s currently experiencing strong headwinds as OPEC pushes the cost of oil down to the $50 range from the $100-110 range last year.  It’s economically unfeasible to frack for natural gas with $50 per barrel of oil.  While the natural gas industry won’t collapse (at least I hope it doesn’t), it won’t support additional decarbonization for the foreseeable future either.

I believe we are well on our way toward 3-4C warming by 2100 and must plan and act accordingly.  This deal, while diplomatically ambitious, is not climate ambitious enough to drive us away from those thresholds.


Can Carbon Emissions Be Reduced In Electricity Generation While Including Variable Renewables? A California Case Study

This is a class paper I wrote this week and thought it might be of interest to readers here.  I can provide more information if desired.  The point to the paper was to write concisely for a policy audience about a decision support planning method in a subject that interests me.  Note that this is only from one journal paper among many that I read every week between class and research.  I will let readers know how I did after I get feedback.  As always, comments are welcome.

40% of the United States’ total carbon dioxide emissions come from electricity generation.  The electric power sector portfolio can shift toward generation technologies that emit less, but their variability poses integration challenges.  Variable renewables can displace carbon-based generation and reduce associated carbon emissions.  Two Stanford University researchers demonstrated this by developing a generator portfolio planning method to assess California variable renewable energy penetration and carbon emissions (Hart and Jacobson 2011).  Other organizations should adopt this approach to determine renewable deployment feasibility in different markets.

The researchers utilized historical and modeled meteorological and load data from 2005 in Monte Carlo system simulations to determine the least-cost generating mix, required reserve capacity, and hourly system-wide carbon emissions.  2050 projected cost functions and load data comprised a future scenario, which assumed a $100 per ton of CO2 carbon cost.  They integrated the simulations with a deterministic renewable portfolio planning optimization module in least-cost and least-carbon (produced by minimizing the estimated annual carbon emissions) cases.  In simulations, carbon-free generation met 2005 (99.8 ± 0.2%) and 2050 (95.9 ± 0.4%) demand loads in their respective low-carbon portfolios.

System inputs for the 2005 portfolio included hourly forecasted and actual load data, wind speed data generated by the Weather Research and Forecasting model, National Climatic Data Center solar irradiance data, estimated solar thermal generation, hourly calculated state-wide aggregated solar photovoltaic values, hourly temperature and geothermal data, and approximated daily hydroelectric generation and imported generation.  They authors calculated 2050 load data using an assumed annual growth rate of 1.12% in peak demand and 0.82% growth in annual generation.

The Monte Carlo simulations addressed the uncertainty estimation of different system states.  As an example, the authors presented renewables’ percent generation share and capacity factor standard deviations across all Monte Carlo representations.  The portfolio mix (e.g., solar, wind, natural gas, geothermal, and hydroelectric), installed capacities & capacity factors of renewable and conventional energy sources, annual CO2 emissions, expected levelized cost of generation, and electric load constituted this method’s outputs.

A range of results for different goals (i.e., low-cost vs. low-carbon), the capability to run sensitivity studies, and identification of system vulnerabilities comprise this method’s advantages.  Conversely, this method’s cons include low model transparency, subjective definition and threshold of risk, and a requirement for modeling and interpretation expertise.

This method demonstrates that renewable technologies can significantly displace carbon-based generation and reduce associated carbon emissions in large-scale energy grids.  This capability faces financial, technological, and political impediments however.  Absent effective pricing mechanisms, carbon-based generation will remain cheaper than low-carbon sources.  The $100 per ton of CO2 assumption made in the study’s 2050 portfolio is important, considering California’s current carbon market limits, its initial credit auction price of $10.09 per metric tonne (Carroll 2012), and its a $50/ton price ceiling.  In order to meet the projected 2050 load with renewable sources while reducing emissions, technological innovation deserves prioritization.  More efficient and reliable renewable generators will deliver faster investment returns and replace more carbon-based generators.  Improved interaction with all stakeholders during the planning phase of this endeavor will likely reduce political opposition.

Carroll, Rory. 2012. “California Carbon Market Launches, Permits Priced Below Expectations.” Reuters, November 19.

Hart, E. K., and M. Z. Jacobson. 2011. “A Monte Carlo Approach to Generator Portfolio Planning and Carbon Emissions Assessments of Systems with Large Penetrations of Variable Renewables.” Renewable Energy 36 (8): 2278–2286.


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