Working Paper Series

 

This is a Working Paper Series, therefore intended to facilitate discussion on research in progress. Working papers represent the opinions of the authors, and are not meant to represent the position or opinions of the authors’ institutions. Any errors are the fault of the authors. Working papers published under this Series may subsequently be published elsewhere.

 

Working Paper 009: Cost-effective decarbonization of California’s power sector by 2030 with the aid of battery storage (download working paper)

Abstract

The costs of solar photovoltaics (PV), wind, and battery storage have fallen by approximately 65% to 85% since 2010 and are projected to decline further in the near future—creating opportunities for aggressive power-sector decarbonization that were seldom envisioned even a few years ago. We assess the ability of large-scale PV and wind deployment in conjunction with modest amounts of battery storage to enable near-complete decarbonization of California’s power sector by 2030. Our study improves on previous analyses by accounting for the dramatic recent cost reductions and therefore assessing the possibility of more rapid decarbonization. We find that, even if renewable energy and storage costs do not decline further, a carbon-free generation share of 80% can be achieved by 2030 in California at a total system cost lower than the cost in a baseline no-additional-cleanenergy scenario. If costs decline at half the rate observed since 2010, 95% carbon-free generation is feasible at a total system cost similar to the cost in a baseline scenario. This is the first study to suggest California could cost-effectively achieve near-complete power-sector decarbonization by 2030 using existing technologies. The results also indicate potential for similar opportunities in other regions of the world. This is especially important because power-sector decarbonization could catalyze electrification-based decarbonization across other economic sectors such as transportation, buildings, and industry.

 

Working Paper 008: Bottom-up estimation pf the end-use level load and demand response potential in India (download working paper)

Abstract

Over the next 15 years, electricity demand from the key residential and commercial appliances is projected to be nearly 300 GW or ~65% of India’s total peak demand. The objective of this study is to characterize appliance level demand and temporal variation, and identify the overall DR potential in India. We use Bangalore Electricity Supply Company territory (peak load of 3,505 MW in 2016) as a case study, using actual one-minute resolution load data for 2,979 distribution feeders and a detailed load survey. Our results show that agricultural pumping and space cooling (residential, commercial, and industrial) are the main contributors to the peak demand – with shares of 23-27% and 14-23%, respectively. Both sectors have about 1,000 MW of DR potential – agricultural pumps offering load shifting service while space cooling offering shimmy service that is capable of dynamically adjusting to react to short-run ramps and grid disturbances. Residential electric water heaters contribute nearly 18% of the winter morning peak demand and can also offer about 500 MW in shimmy service. Overall, we find that shifting and shimmy services offer 1,199 MW and 1,511 MW total DR potential, respectively.

 

Working Paper 007: Sunsetting Coal Power in China (download working paper)

Abstract

Reducing CO2 emissions from coal-fired electricity generation in China will be critical to global efforts to limit global warming. Long-term projections of China’s electricity supply tend to assume that coal generation will be a mainstay of China’s electricity system through 2050, but it is unclear if and when carbon capture and storage will be viable at scale. This paper uses an analytical model to examine the resource, economic, and institutional implications of reducing and replacing coal generation in China with mostly renewable energy by 2040. We find that the scale of solar, wind, and storage resources needed to do so is extremely large — on the order of 100-150 GW yr-1 of solar and wind capacity and 15 GW yr-1 of battery storage from 2020 to 2025, growing to 250 GW yr-1 and 90 GW yr-1, respectively, from 2025 to 2040. However, the scale of new generation resources needed to meet 3-5 PWh (10-17 EJ) yr-1 of expected electricity demand growth in China by 2040 (relative to 2018) will be extremely large regardless of technology choices. Although the idea of terawatt-scale development of solar, wind, and batteries will naturally raise questions around feasibility, more important questions are around future technology costs (actual, not modeled), changes in institutions needed to support a mostly renewable electricity system in China, and transition issues.  

 

Working Paper 006: Economic and environmental benefits of market-based power-system reform in China: provincial versus regional grid optimization (download working paper)

Abstract

China, whose power system accounts for about 13% of global energy-related CO2 emissions, has begun implementing market-based power-sector reforms. This paper simulates power system dispatch in China’s Southern Grid region and examines the economic and environmental impacts of market-based operations. We find that market-based operation can increase efficiency and reduce costs in all Southern Grid provinces—reducing wholesale electricity costs by up to 35% for the entire region relative to the 2016 baseline. About 60% of the potential cost reduction can be realized by creating independent provincial markets within the region, and the rest by creating a regional market without transmission expansion. The wholesale market revenue is adequate to recover generator fixed costs; however, financial restructuring of current payment mechanisms may be necessary. Electricity markets could also reduce the Southern Grid’s CO2 emissions by up to 10% owing to more efficient thermal dispatch and avoided hydro/renewable curtailment. The benefits of regional electricity markets with expanded transmission likely will increase as China’s renewable generation increases.

 

Working Paper 005: Long-haul battery electric trucks are technically feasible and economically compelling (download working paper, executive summary)

 Abstract

Zero emission freight trucks are critical to meet global climate goals and reduce air pollution. Technological constraints and economic conditions have generally suggested that electrifying this sector is challenging; however, the emerging reality is different. We assess how recent dramatic improvements in battery technology make it technically feasible and potentially economically attractive to electrify heavy-duty trucking if charging infrastructure needs are met and cost-effective electricity pricing is available. We use the latest data on battery technology and detailed component-level cost and performance data for trucks to estimate the total cost of ownership of electric trucks. We estimate the TCO of an electric truck to be $1.27/mile, 20% less than that of a diesel truck, assuming trucks can access average industrial electricity prices of about $0.07/kWh which require reforms in electricity tariffs to make demand and transmission charges peak-coincident. We find that if environmental externalities, such as air pollution and greenhouse gas emissions are monetizable, the TCO of an electric truck could be as low as $0.95/mile, 40% lower than a diesel truck. We also show that electric trucks with a 250-mile range can have the same weight as diesel trucks with realistic improvements to battery packing fractions, and that weight parity for 500-mile-range trucks is achievable with commercially available lightweighting options and about 3.5% reduction in maximum payload capacity. We conclude that adequate fast charging infrastructure and electricity prices that reflect true system costs can unlock a major environmental and economic opportunity by enabling electrification of freight. If battery prices continue to fall and battery pack density continues to increase at even half the current rates, long-haul battery electric trucks will become dramatically more attractive.

 

Working Paper 004: Big Batteries on WheelsThe economic, environmental, and resilience case for rapidly converting diesel locomotives to battery-electric (download working paper)

Abstract

The U.S. rail sector is responsible for significant air pollution damages due to its dependence on diesel-based propulsion. One pathway to a zero-emission rail sector involves electrifying railway tracks and using emission-free electricity which requires significant storage combined with renewable electricity on the grid. We consider an alternate pathway, adding battery storage cars to diesel-electric trains. This approach would enable the rail sector to store and run on renewable electricity while obviating the need to electrify tracks. We show that the dramatic declines in the cost of battery storage and renewable energy present an opportunity to eliminate rail emissions cost effectively. We build a bottom-up cost model to explore the technical feasibilityand costs of retrofitting diesel-electric trains with large batteries. We show that a single railcar carrying a 9-MWh battery is sufficient to power an average Class I freight train for 150 miles, the average distance traveled in a day. We establish a baseline scenario with high charging costs, no consideration of environmental benefits, and no further decline in battery prices, and we compare it against scenarios with lower charging costs, lower battery prices, and valuation of environmental benefits. Across these scenarios, the 20-year net present value of savings for the U.S. freight rail sector ranges from a cost of $54 billion to savings of $250 billion. In addition, a battery-electric rail sector would provide more than 200 GWh of modular and mobile storage, which could provide grid services and improve the resilience of the power system.


Working Paper 003: Reforming electricity rates to enable economically competitive electric trucking (download working paper)

Abstract

The imperative to decarbonize long-haul, heavy-duty trucking for mitigating both global climate change as well as air pollution is clear. Given recent developments in battery and ultra-fast charging technology, some of the prominent barriers to electrification of trucking are dissolving rapidly. Here we shed light on a significant yet less-understood barrier, which is the general approach to retail electricity pricing. We show that this is a near term pathway to $0.06/kWh charging costs that will make electric trucking substantially cheaper than diesel. This pathway includes i) reforming demand charges to reflect true, time-varying system costs; ii) avoiding charging during a few specific periods (<45 hours in a year) when prices are high; and iii) achieving charging infrastructure utilization of 33% or greater.

 

Working Paper 002: Electrifying urban ridesourcing fleets at no added cost through efficient use of charging infrastructure (download working paper, executive summary)

Abstract

Ridesourcing fleets present an opportunity for rapid uptake of battery electric vehicles (BEVs) but adoption has largely been limited to small pilot projects. Lack of charging infrastructure presents a major barrier to scaling up, but little public information exists on the infrastructure needed to support ridesourcing electrification. With data on ridesourcing trips for New York City and San Francisco, and using agent-based simulations of BEV fleets, we show that given a sparse network of three to four 50kW chargers per square mile, BEVs can provide the same level of service as internal combustion engine vehicles (ICEVs) at lower cost. This suggests that the cost of charging infrastructure is not a significant barrier to ridesourcing electrification. With coordinated use of charging infrastructure across vehicles, we also find that fleet performance becomes robust to variation in battery range and placement of chargers, suggesting that such capability may help enable electrification. Our results suggest that mandates for ridesourcing electrification could encourage efficient utilization of fast-charging infrastructure, bringing down costs for all BEV users without significantly increasing the cost of ridesourcing services.

 

Working Paper 001: The case for policies to target electric vehicle miles (download working paper)

Abstract

The rationale for public support of battery electric vehicles (BEV) is sound. However, in spite of subsidies for vehicle purchase and other incentives, BEVs remain costly. Here, we argue that while lump-sum investment subsidies have some advantages at the very early stages of diffusion, given some salient developments in personal transportation, the timing is just right for a delivering subsidies in a more targeted manner. Use-based incentives together with financial assistance for BEV purchase and creation of a fast-charging infrastructure, would exploit the proliferation of high-use vehicles associated with on-demand transportation services while also continuing to support BEV adoption for private household use. Such a shift has the potential to deliver greater environmental benefits faster, directly benefit poorer households, and can be designed to minimize transaction costs.