Opportunities in energy: National policy approaches for addressing climate change

Opportunities in energy: National policy approaches for addressing climate change

The Electricity Journal 33 (2020) 106693 Contents lists available at ScienceDirect The Electricity Journal journal homepage: www.elsevier.com/locate...

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The Electricity Journal 33 (2020) 106693

Contents lists available at ScienceDirect

The Electricity Journal journal homepage: www.elsevier.com/locate/tej

Opportunities in energy: National policy approaches for addressing climate change

T

Sandra Sattler*, Steve Clemmer, Jeremy Richardson, Rob Cowin Union of Concerned Scientists, United States

A R T I C LE I N FO

A B S T R A C T

Keywords: Electricity modeling Low carbon electricity standards Carbon pricing Climate change Public health Coal plant retirements

Last year’s Intergovernmental Panel on Climate Change (IPCC) report and the Fourth National Climate Assessment both showed that to limit the worst consequences of climate change by keeping global average temperature increases to 1.5 C, the United States and other countries must achieve net-zero heat-trapping emissions economy-wide by mid-century, with nearly half of those reductions occurring by 2030. Decarbonizing the electric sector is one of the most cost-effective ways to reduce emissions and can help decarbonize other sectors with increased electrification. While renewable energy and energy efficiency have grown significantly in recent years due to technology cost reductions, state policies, and federal tax incentives, our rate of emissions reduction does not go far enough. Our analysis shows that a well-designed national Low Carbon Electricity Standard (LCES), Renewable Electricity Standard (RES), or increasing carbon price can help get the U.S. on a pathway for decarbonizing the power sector by 2050. The most cost-effective strategy for reducing emissions in the near-term is through the increased deployment of wind and solar, regardless of the policy. How much the generation mix shifts to low-carbon resources is a function of the stringency of the policy. These policies can also spur the development of low-carbon electricity in parts of the country that are not as far along in their transition to a clean energy economy. Allowing a wide range of carbon-free and low-carbon resources to compete against each other could deliver the most low-carbon electricity at the lowest cost and help broaden support for these policies.

1. Introduction Last October, a United Nation’s report concluded that the goal of keeping global average temperatures from rising above 1.5 °C (2.7 °F) will require reaching “net zero” emissions by mid-century (IPCC, 2018). A month later, the Fourth National Climate Assessment presented the starkest assessment to date of the national consequences of climate change (NCA 2018). The report projected that climate-related impacts will only get worse and their costs will mount dramatically if carbon emissions continue unabated. Annual losses in some sectors are projected to exceed $100 billion by the end of the century and surpass the gross domestic product of many states. Many studies show that decarbonizing the electric sector is one of the most cost-effective ways to limit emissions and can help decarbonize other sectors with increased electrification (Union of Concerned Scientists (UCS, 2016; IPCC, 2018; Mai et al., 2018; White House, 2016; Evolved Energy Research, 2019). There are many different pathways and policy levers to achieve the levels of emission reduction needed to prevent the worst consequences of climate change. In the U.S., there is momentum at various levels of



Corresponding author. E-mail address: [email protected] (S. Sattler).

https://doi.org/10.1016/j.tej.2019.106693

1040-6190/ © 2019 Published by Elsevier Inc.

government and in the private sector to limit the production of heattrapping emissions:

• 8 states, Washington D.C., and Puerto Rico have adopted 100 % CE targets • Twenty-nine states have adopted renewable portfolio standards • • •

(RPS) that require electric utilities to purchase increasing amounts of renewable energy. Over 130 US cities have committed to 100 % renewable energy (Sierra Club 2019) https://www.sierraclub.org/ready-for-100/ commitments 194 major corporations have also committed to 100 % renewable energy (http://there100.org/companies Over 3500 leaders from across the country have signed on to uphold the Paris Agreement, including governors, mayors, county executives, tribal leaders, college and university leaders, businesses, faith groups, and investors (We Are Still In 2019) While this is a good start, much more needs to be done to get the US

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until they hit 60 % existing carbon-free electricity (1.75 % till they hit 90 %), while the Udall RES requires that utilities grow at 2 % through the next decade and 2.5 % through 2035, until they hit at least 60 % renewable electricity.

on a pathway to get to net-zero emissions by 2050. What is needed is a national policy for renewable energy or low-carbon electricity. There has been increased public discourse around a range of policy proposals to help decarbonize the economy, including RES and CES proposals in Congress, and proposals to extend federal RE tax credits. The Green New Deal, while not policy prescriptive, also includes an ambitious platform for emissions reductions across the economy including in the power sector. The debate around these proposals have asked questions about affordability, stringency (or ambitiousness), and achievability of the policy. Studies by the Union of Concerned Scientists (UCS) and others (National Renewable Energy Laboratory (NREL, 2012; IPCC, 2018; Evolved Energy Research (EER, 2019) show that policies that incentivize an aggressive but achievable level of renewable energy can affordably meet mid-century decarbonization goals. This paper analyzes three recently proposed federal clean energy policies: a national Renewable Energy Standard (RES) a national Low Carbon Electricity Standard (LCES), and a national carbon price. Our analysis contributes to the public discourse on policy proposals by showing ambitious and feasible pathways to reach policy goals shared by a range of stakeholders. There is an urgent need for an effective federal clean energy policy. This report shows how both a national RES and LCES get us on the path to achieve net-zero emissions by mid-century in a realistic, affordable fashion. Our analysis has found that:

These federal standards are both market-based approaches that create competition among clean-energy technologies, projects and companies to provide the greatest amount of clean power for the lowest price and provide ongoing incentive to drive down costs. Currently existing state RESs have demonstrated deployment of renewables (Lawrence Berkeley National Laboratory (LBNL, 2019); creating jobs and driving down emissions in these states. These successes at the state level can serve as a model for a federal policy. Scaling up these examples can help inform good policy design by taking working policy that voters are already familiar with. 3. Methodology To analyze a national RES, LCES, and a national carbon price, we used a modified version of the Regional Energy Deployment System (ReEDS)1 . ReEDS is a power-sector dispatch model that simulates the electricity-supply mix that would meet electricity demand in the future throughout the contiguous United States at the lowest overall system cost while meeting reliability, environmental, and other legal requirements. The assumptions in our version of the model are based on:

• A national LCES, RES, and a national carbon price get us on the path to net-zero by 2050 • All policies are achievable and affordable relying primarily on technologies that are commercially available • These conclusions are in line with other recent research (NREL,

• Information used by the Energy Information Administration for the Annual Energy Outlook 2018 (EIA 2018b) • The natural gas price projection from EIA’s AEO 2018 “high oil and • •

IPCC)

2. Recent federal clean energy proposals The senate currently has two proposals that would create a national standard for low-carbon electricity generation. In May, Senator Tina Smith (D-MN) introduced the Clean Energy Standard Act (S. 1359) which would decarbonize the power sector by mid-century using a variety of low and zero carbon technologies. In June, Senator Tom Udall (D-NM) introduced the Renewable Electricity Standard Act (S. 1974), a bill that would more than double the supply of renewable energy to least 50 percent by 2035 by ramping up renewable electricity generation in every state over the next 15 years. Both the CES and RES would require electric utilities to gradually increase the amount of renewable (wind, solar, geothermal, biomass and hydropower) energy in their power supplies over time The CES would also allow clean energy (nuclear and fossil with CCS) to compete with renewable energy in the generation mix. These two proposals take different approaches toward the same goal of transitioning all electricity generation to carbon free sources in a time horizon consistent with the best available climate science, and they do so while preserving the voluntary markets and without interfering with state policy. Here are some ways the two proposals compare:



For this analysis we modeled the following scenarios:

• Reference case. We first modeled a Reference case with state and •

• The Smith CES goes till 2050, while the Udall RES goes till 2035 • • •

gas resource and technology side case to be consistent with historical gas prices. NREL’s 2018 Standard Scenarios reports (National Renewable Energy Laboratory (NREL, 2018). The load projection from EIA’s AEO 2018 reference case, adjusted for current state-level energy efficiency programs (American Council for an Energy-Efficient Economy (ACEEE, 2018). Updated data on state RES policies from Lawrence Berkeley National Lab and recent retirements of existing power plants and new power plants under construction from S&P Global Market Intelligence (S& P, 2019) (see the technical appendix, online at www.ucsusa.org, for more information).



with a requirement to consider revising and extending the policy to decarbonize the power sector by 2050. The Smith CES credits both new and existing renewables, nuclear, and fossil energy with carbon, capture and sequestration (CCS), while the Udall RES mostly credits new renewables like wind and solar, with very little existing generation. Both bills focus on “growth rates” rather than an overall national percentage target by a certain year. The Smith CES would ask utilities to grow by 2.75 % every year

federal policies in place as of May 2019, and the assumption that no additional policies have been or will be implemented. RES case. To serve as a proxy for S. 1974, our RES case includes a national RES of 22.8 percent in 2020, increasing to 42.2 percent in 2030 and 53.2 percent in 2035 layered over the Reference case. We assumed that several renewable energy technologies would be eligible to meet the standard, including hydro, wind, solar, biomass, and geothermal. These national RES targets also reflect different ramp-up rates for small and large utilities (with sales above and below 1 million MWh per year) and assumptions about utilities and states that may opt-out of the policy when they reach 60 percent of sales from renewables, as specified in S. 1974. LCES case. Our LCES case models a 95 percent by 2050 Clean Energy Standard. Our modeling for this scenario was completed before S. 1359 was released, but the targets are similar to the bill and can help inform discussion of a national LCES (Resources for the Future (RFF, 2019)..Our LCES case layers a national LCES of 45 percent by

1 ReEDS is a power-sector dispatch model developed by the National Renewable Energy Laboratory (NREL), https://www.nrel.gov/analysis/reeds/.

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2020, 65 percent by 2030, and 72.5 percent by 2035 over the Reference case. We assumed that several technologies would be eligible to meet the standard, including new and existing nuclear plants, renewable energy technologies (from hydro, wind, solar, biomass, and geothermal), and natural gas and coal plants equipped with carbon capture and storage (CCS), with capture rates of 90 percent or more. We assumed that nuclear and renewable energy facilities would get full credit toward the standard and CCS projects would receive partial credit based on their capture rate (e.g., a CCS project that captures 90 percent of CO2 emissions would be credited at 90 percent of its generation). Carbon Price case. Our Carbon Price case is based on the EIA’s Annual Energy Outlook 2018 economy-wide CO2 price of $25 per ton in 2020, increasing at 5 percent per year (EIA 2018a). This case also analyzed the impact of a national energy efficiency standard, assuming that all states achieve a modest reduction in electricity sales of at least 1 percent per year from 2022 to 2030 and that states with stronger energy efficiency standards continue meeting their respective targets (Deyette et al., 2016). Leading states currently meet energy efficiency targets of 2–3 percent per year (Weston et al., 2017). This energy-efficiency policy is modeled as a reduction in electricity demand in ReEDS, with the costs of implementing the policy and net savings on consumer electricity bills estimated outside the model.

Fig. 2. U.S. Power Plant Carbon Dioxide Emissions. Caption: Power plant CO2 emissions the U.S. initially decline and then increase in the 2030–2035 timeframe as natural gas generation increases in this case. CO2 emissions decrease under all the federal clean energy policy cases.

carbon electricity instead of natural gas. The renewable energy share of the total generation by 2035 is similar under all three policies (over 50 percent) because renewable energy technologies (mostly wind and solar) are the most cost-effective way to generate low-carbon electricity in the near-term Fig. 2. 5. Clean energy investments

4. Federal clean energy policies lead to lower emissions and more clean energy investments

The renewable energy deployment under a national clean energy policy would accelerate our nation’s transition to low-carbon electricity. It would build on the recent growth in renewable energy jobs in manufacturing, construction, operation, maintenance, and many other industries and would drive significant investment across the economy. To meet the LCES, RES, and carbon price, the U.S. would add 113–149 GW of new wind capacity and 150–332 GW of new solar capacity above the Reference case by 2035. Without a national policy, renewables do increase by a modest amount to take advantage of the federal tax credits for renewables and due to decreases in cost of clean energy. Building additional new renewable energy capacity under a national clean energy policy would drive a total of $213-359 billion in new capital investments.2 As a result, total installed renewable energy capacity will reach 263–480 GW by 2035. To help integrate increasing levels of variable wind and solar generation, energy storage capacity would nearly triple to 64 GW by 2035 in the RES case, 95 GW in the LCES case, 113 GW in the Carbon Price case, 32–81 GW more than the reference case. In addition, US transmission capacity would increase by 3–4 percent for AC lines and 10–35 percent for DC lines, for a combined increase of 3.4–4.6 million MWmiles, compared to the reference case. A national clean energy policy would deliver the following economic benefits:

With federal clean energy policies, the U.S. can accelerate its shift toward cleaner, low-carbon energy resources. Under the Reference case – that is, a future without a federal clean energy policy – natural gas generation would see significant growth, increasing from 35 % of the US electricity mix in 2018 to 58 % by 2035 (Fig. 1). Most of this new natural gas generation would replace retiring coal plants and some existing nuclear reactors. This level of dependence on natural gas would pose significant risks to consumers and the US economy from potential supply shortages and price volatility. Under the RES, renewable generation would roughly double by 2035 compared to the reference case, reducing natural gas generation by 38 percent and nearly phasing out the relatively small amount of remaining coal generation. The LCES case showed slightly less renewable growth by 2035 (an increase of 84 percent compared to the reference case) and would reduce natural gas generation by 43 percent. The carbon price case showed an increase in renewable generation of 65 percent compared to the reference case and would reduce natural gas generation by 30 percent. A LCES and a carbon price would also help preserve existing nuclear generation while both policies would ensure that any nuclear retirements are replaced primarily with zero-

• $8-12 billion in annual operation and maintenance payments in 2035 • $3.1–5.6 billion in cumulative property tax payments to local governments from 2020-2035 • $0.5-1.4 billion in cumulative wind power land lease payments to rural landowners from 2020-2035

6. Emission reduction Increasing renewable energy use is a smart, cost-effective way to reduce carbon dioxide (CO2) emissions. A national clean energy policy would put the US on course to decarbonize the power sector and meet the Paris Climate Agreement. The reference case generation mix causes

Fig. 1. U.S. Electricity Generation. Caption: Analysis of federal clean energy policy proposals show that the U.S. can transition to a more diversified portfolio of clean and low-carbon energy resources beyond what current policies are already set to achieve.

2 Assuming a 7 percent discount rate, based on recommendations outlined in Office of Management and Budget (OMB, 2014.

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money). However, for the nearly half of U.S. homes that heat with natural gas, typical annual natural gas bills would be $36-45 lower in 2030 and $64-94 lower in 2035. Lower natural gas bills for industrial and commercial consumers would also offset slightly higher electricity bills. 7. Economic and public health benefits from less air pollution Under the reference case, electricity-related CO2 emissions flatten out and then increase after 2030, reaching 1063 million metric tons by 2035. A national clean energy policy would reduce carbon emissions in 2035; by 46 percent for the RES Case and by 44 percent for the LCES Case, 36 % for the Carbon Price Case (Fig. 3). Cumulatively from 2016 through 2035, all cases result in a 4–6 billion ton reduction in CO2 emissions. The lower CO2 emissions directly reflect the nation’s cleaner generation mix (see Fig. 1) spurred by renewable energy and clean energy policies. In addition to reducing CO2 emissions, all clean energy policies also help cut other air pollutants—including sulfur dioxide (SO2) and nitrogen oxides (NOx)—primarily through the reduction in coal generation from older and inefficient plants. Under all the policy cases, NOx emissions are 61–69 percent lower in 2035 than the reference case, while SO2 emissions are 41–52 percent lower. Reducing NOx, SO2, and CO2 emissions leads to tangible health and environmental benefits. NOx contributes to smog and NOx and SO2 contribute to soot, which exacerbates asthma and other heart and lung diseases and can result in significant disability and premature death from these causes (EPA n.d.). CO2 emissions contribute to global climate change, which leads to sea level rise, extreme weather such as heat waves, droughts, and heavy downpours, and to other climate impacts that can impair human health and safety. Using the same methodology applied by the EPA in its impact assessment for the Clean Power Plan (CPP), we estimated the monetized savings from reducing these pollutants.3 The combined carbon and health dollar-benefits of the avoided emissions of CO2, SO2, and NOx show large national benefits. Under the national clean energy policy cases, the climate and public health benefits are over $15-18 billion on average each year from 2020 to 2035. Cumulatively through 2035, these benefits range from $131 to $166 billion4 across the cases.

Fig. 3. U.S. Average Retail Electricity Prices. Caption: Average retail electricity prices increase under all of the federal clean energy policy cases compared to the reference case. But savings due to lower natural gas prices and energy efficiency investments result in cumulative net savings for all policies.

power sector CO2 emissions to flatten out and then increase after 2030 due to the increase in natural gas generation and only a modest increase in renewable generation. By contrast, all three federal clean energy policy cases result in cleaner and more diversified generation mixes. Federal clean energy policies reduce fossil fuel-based electricity generation and result in 31, 29 and 34 percent decrease in CO2 emissions by 2030 for the RES, LCES, and Carbon Price cases respectively, and 46, 44, and 36 percent decrease by 2035, compared to Reference case levels (Fig. 3). The CO2 emissions in these cases are 75, 74, and 70 percent below 2005 levels in 2035 in the RES, LCES, and Carbon Price cases, respectively. Cumulatively, the national clean energy policies would reduce CO2 reductions by 4–6 billion metric tons from 2020-2035. Coal generation is 97 percent lower in the RES case than in the Reference case by 2035, 84 percent lower in the LCES case, and coal generation falls to zero in the Carbon Price case. While these national clean energy policies do cut emissions in the power sector, additional economy-wide climate and clean energy policies will be needed to meet U.S. climate goals.

8. National energy standards offer pathways to US leadership on clean energy

6.1. A cleaner energy supply is affordable Clean energy growth in the U.S. is not only achievable but also affordable and can provide important benefits for consumers. The cost of wind and solar has fallen by more than 70 percent over the past decade, making renewable energy more affordable for consumers. By increasing competition and diversifying power supplies, renewable energy reduces the demand for fossil fuels, leading to lower and more stable natural gas prices for all consumers. Under both the national LCES and RES, power sector natural gas prices are 23–35 percent lower than the reference case in 2035. The significant reduction in power sector natural gas use would also result in lower costs for homes and business that use natural gas for heating, manufacturing, and other purposes. By 2035, average retail electricity prices are 5.6–6.7 percent higher under all the policy cases compared to the reference case, but only 0.10.2 percent higher than current levels (Fig). However, the reduction in natural gas prices more than offsets the increase in electricity prices, resulting in $34–66 billion (0.6–1.2 percent) in cumulative net savings on combined consumer natural gas and electricity bills from 20202035. A typical household using 600 kW h per month would pay $12-18 per year in higher electricity bills in 2030, and $6-51 more in 2035 compared to the Reference case (both the LCES and Carbon Price cases include increased levels of energy efficiency, saving the consumer

While the three policies deploy a similar amount of renewables by 2035, the location of those renewables would likely be different given the different policy designs. The Udall RES bill would likely distribute renewables more evenly around the country, with better penetration in laggard clean energy states. But the LCES case reduces slightly more power-sector emissions cumulatively by 2035 (19 percent in the LCES analysis relative to 18 percent for the RES case), the primary reason being that it requires utilities to grow at 2.67 % low-carbon generation immediately, which could be challenging for states that are adding renewables at or below the national average of 1 percent annually. The cost of the LCES case is slightly lower because we assumed it would be implemented along with complementary policies for energy efficiency. In addition, it helps preserve the carbon-free generation of existing nuclear power plants and delivers about 7 percent electricity from natural gas with CCS by 2035. 3 The health benefits are calculated based on Benefit per Ton Estimates for SO2 and NOx, reported in Tables 4A-2 to 4A-5 of EPA 2015. See the technical appendix, online at www.ucsusa.org/, for values and additional information. 4 This is the net present value from 2022 through 2030 using a 7 percent discount rate, based on recommendations outlined in Office of Management and Budget (OMB, 2014.

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From our analysis, we can see that both the national RES and LCES policies would put the U.S. on course for decarbonizing the power sector by mid-century under the currently projected electricity load. Increased electrification of all sectors and energy efficiency will be necessary to decarbonize our economy (Mai et al., 2018), but what was modeled here was the projected electricity load under currently existing legislation and policies. All policies analyzed here are affordable and have considerable economic, public health and consumer benefits. All policies are designed to optimize the least-cost mix of electricity generation technologies, but an LCES would also help preserve existing low-carbon nuclear generation and jobs in that industry and encourage investments in CCS. While all proposed clean-energy policies dramatically cut carbon from the electricity sector, additional climate and clean energy policies will be needed to meet US climate goals. This includes policies like a carbon cap, stronger energy efficiency standards, increased funding for clean energy R&D and infrastructure investments, and incentives for greater electrification of transportation, buildings and industry. Considering the significant economic, consumer, and climate benefits, a strong national clean energy policy should be a top priority as Congress considers new policies to transition America to a low-carbon energy future.

Special Report on the Impacts of Global Warming of 1.5°C Above pre-Industrial Levels and Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change, Sustainable Development, and Efforts to Eradicate Poverty. World Meteorological Organization, Geneva, Switzerland 32 pp. Lawrence Berkeley National Laboratory (LBNL), 2019. US Renewable Portfolio Standards Annual Status Report. Online at https://emp.lbl.gov/projects/renewables-portfolio, (Accessed May 2019). . Mai, Trieu, Jadun, Paige, Logan, Jeffrey, McMillan, Colin, Muratori, Matteo, Steinberg, Daniel, Vimmerstedt, Laura, Jones, Ryan, Haley, Benjamin, Nelson, Brent, 2018. Electrification Futures Study: Scenarios of Electric Technology Adoption and Power Consumption for the United States. NREL/TP-6A20-71500. National Renewable Energy Laboratory, Golden, CO. https://www.nrel.gov/docs/fy18osti/71500.pdf. National Renewable Energy Laboratory (NREL), 2018. 2018 Annual Technology Baseline. National Renewable Energy Laboratory, Golden, CO. https://atb.nrel.gov/. National Renewable Energy Laboratory (NREL), 2012. In: Hand, M.M., Baldwin, S., DeMeo, E., Reilly, J.M., Mai, T., Arent, D., Porro, G., Meshek, M., Sandor, D. (Eds.), Renewable Electricity Futures Study. National Renewable Energy Laboratory, Golden, CO 4 vols. NREL/TP-6A20-52409. http://www.nrel.gov/analysis/re_ futures/. Office of Management and Budget (OMB), 2014. Circular A-94: Guidelines and Discount Rates for Benefit-cost Analysis of Federal Programs. Washington, DC. . Resources for the Future (RFF), 2019. Projected Effects of the Clean Energy Standard Act of 2019. Washington, DC. . S&P Global Market Intelligence. 2019. online at https://platform.mi.spglobal.com (paywall restricted). Union of Concerned Scientists (UCS), 2016. The U.S. Power Sector in a Net Zero World. Cambridge, MA. Online at https://www.ucsusa.org/sites/default/files/attach/2016/ 11/UCS-Deep-Decarbonization-working-paper.pdf?_ga=2.58892333.1849192985. 1568658038-1310907552.1550089632, (Accessed 16 September 2019). . Weston, B., Nowak, S., Kelly, M., Vaidyanathan, S., Shoemaker, M., Chittum, A., DiMascio, M., DeLucia, H., 2017. State Energy Efficiency Scorecard. American Council for an Energy Efficient Economy, Washington, DC. Report U1710. Online at https://aceee.org/researchreport/u1710, (Accessed 5 November 2018). White House, 2016. U.S. Mid-century Strategy for Deep Decarbonziation. November. . http://unfccc.int/files/focus/long-term_strategies/application/pdf/mid_century_ strategy_report-final_red.pdf.

References American Council for an Energy-Efficient Economy (ACEEE), 2018. The State Energy Efficiency Scorecard. Online at https://aceee.org/state-policy/scorecard, (Accessed on 1 March 2019). . Deyette, J., Sattler, S., Bailie, A., Cleetus, R., Clemmer, S., Garcia, P., 2016. The Clean Power Plan Opportunity: Securing Economic and Clean Energy Benefits for All of the States. Union of Concerned Scientists, Cambridge, MA Online at www.ucsusa.org/ sites/default/files/attach/2016/ 03/national-clean-power-plan-analysis.pdf, (Accessed 1 August 2018). Evolved Energy Research (EER), 2019. 350 PPM Pathways for the United States. Evolved Energy Research, San Francisco, CA. https://docs.wixstatic.com/ugd/294abc_ 95dfdf602afe4e11a184ee65ba565e60.pdf. IPCC, 2018. Summary for policymakers. In: Masson-Delmotte, V., Zhai, P., Pörtner, H.-O., Roberts, D., Skea, J., Shukla, P.R., Pirani, A., Moufouma-Okia, W., Péan, C., Pidcock, R., Connors, S., Matthews, J.B.R., Chen, Y., Zhou, X., Gomis, M.I., Lonnoy, E., Maycock, T., Tignor, M., Waterfield, T. (Eds.), Global Warming of 1.5°C. An IPCC

Sandra Sattler is a senior energy modeler in the Climate and Energy Program at the Union of Concerned Scientists. She analyzes and models clean energy, energy efficiency, and global warming policies at the state, regional, and national level. She also quantifies the economic, environmental, and public health impacts that such policies would have on society. Ms. Sattler joined UCS in 2008 after working as an engineer at TIAX LLC and earning her doctorate in mechanical engineering at Cornell University. She holds a B.S. in mechanical engineering from Columbia University and a B.A. in mathematics and physics from Whitman College.

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