Ana Mileva

Deep carbon reductions in California require electrification and integration across economic sectors

Meeting a greenhouse gas (GHG) reduction target of 80% below 1990 levels in the year 2050 requires detailed long-term planning due to complexity, inertia, and path dependency in the energy system. A detailed investigation of supply and demand alternatives is conducted to assess requirements for future California energy systems that can meet the 2050 GHG target. Two components are developed here that build novel analytic capacity and extend previous studies: (1) detailed bottom-up projections of energy demand across the building, industry and transportation sectors; and (2) a high-resolution variable renewable resource capacity planning model (SWITCH) that minimizes the cost of electricity while meeting GHG policy goals in the 2050 timeframe. Multiple pathways exist to a low-GHG future, all involving increased efficiency, electrification, and a dramatic shift from fossil fuels to low-GHG energy. The electricity system is found to have a diverse, cost-effective set of options that meet aggressive GHG reduction targets. This conclusion holds even with increased demand from transportation and heating, but the optimal levels of wind and solar deployment depend on the temporal characteristics of the resulting load profile. Long-term policy support is found to be a key missing element for the successful attainment of the 2050 GHG target in California.

SunShot Solar Power Reduces Costs and Uncertainty in Future Low-Carbon Electricity Systems

The United States Department of Energys SunShot Initiative has set cost-reduction targets of

SWITCH-China: A Systems Approach to Decarbonizing China’s Power System

1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to

Scenarios for Deep Carbon Emission Reductions from Electricity by 2050 in Western North America using the Switch Electric Power Sector Planning Model: California's Carbon Challenge Phase II, Volume II

20 billion (

High-resolution modeling of the western North American power system demonstrates low-cost and low-carbon futures

2010) annually by 2050 relative to scenarios with Reference solar costs.

Addendum: Biomass enables the transition to a carbon-negative power system across western North America

We present an integrated model, SWITCH-China, of the Chinese power sector with which to analyze the economic and technological implications of a medium to long-term decarbonization scenario while accounting for very-short-term renewable variability. On the basis of the model and assumptions used, we find that the announced 2030 carbon peak can be achieved with a carbon price of ∼

Power system balancing for deep decarbonization of the electricity sector

40/tCO2. Current trends in renewable energy price reductions alone are insufficient to replace coal; however, an 80% carbon emission reduction by 2050 is achievable in the Intergovernmental Panel on Climate Change Target Scenario with an optimal electricity mix in 2050 including nuclear (14%), wind (23%), solar (27%), hydro (6%), gas (1%), coal (3%), and carbon capture and sequestration coal energy (26%). The co-benefits of carbon-price strategy would offset 22% to 42% of the increased electricity costs if the true cost of coal and the social cost of carbon are incorporated. In such a scenario, aggressive attention to research and both technological and financial innovation mechanisms are crucial to enabling the transition at a reasonable cost, along with strong carbon policies.

Comparison of low-carbon pathways for California

In this study we use a state-of-the-art planning model for the electric power system - the SWITCH model - to investigate the evolution of the power systems of California and western North America from present-day to 2050 in the context of deep decarbonization of the economy. We find drastic power system carbon emission reductions to be feasible by 2050 under a wide range of possible futures. The average cost of power in 2050 is found to range between

Biomass enables the transition to a carbon- negative power system across western

149/MWh and

Reply to 'Emissions accounting for biomass energy with CCS'

232/MWh across scenarios, a 21 to 88 % increase relative to a business-as-usual scenario, and a 38 to 115 % increase relative to the present-day cost of power. In order to rapidly decarbonize, the power system undergoes sweeping change. Between present-day and 2030, the evolution of the Western Electricity Coordinating Council (WECC) power system is dominated by the implementation of aggressive energy efficiency measures, the installation of renewable energy and gas-fired generation facilities, and the retirement of coal-fired generation. In the 2040 time frame, deployment of wind, solar, and geothermal power reduce power system emissions by displacing gas-fired generation. In the 2050 time frame this deployment trend continues for wind and solar, but is accompanied by large amounts of new storage and long-distance, high-voltage transmission capacity. In stark contrast to present-day operation, electricity storage is used primarily to move solar energy from the daytime into the night in order to charge electric vehicles and meet demand from electrified heating. Transmission capacity over the California border is increased by 40 - 220 % by 2050, implying that transmission siting, permitting, and regional cooperation will become increasingly important over time. California remains a net electricity importer in all scenarios investigated. Wind and solar power are key elements in power system decarbonization, providing 37 - 56 % and 17 - 32 % of energy generated respectively across WECC in 2050 if no new nuclear capacity is built. In an effort to integrate wind and solar resources, the amount of installed gas capacity remains relatively constant between present-day and 2050, though carbon capture and sequestration (CCS) is installed on some gas plants by 2050. The fleet-wide average capacity factor of non-CCS gas generation drops steeply between 2030 and 2050, reaching only 5 - 16 % in 2050 for scenarios that meet the 86 % emission reduction target.