Figure 1 summarizes the energy and power requirements of locomotives, a cruise ship at berth, and California grid capacity. The results show that a large railyard may require infrastructure similar to a shore power connection supplying a single cruise ship.1  It also shows that if all switchers in California were battery electric and charged by the grid, they will account for about 0.1 to 0.2 percent of the 2022 California grid capacity.

Figure 1. Power and energy requirement comparison infographic of battery electric locomotive chargers, Shore Power, and California In-State Electricity Generation.

Power and Energy Requirements

Battery Electric Switchers in a Class I-III Railyard

The analysis calculated power and energy requirements of switchers in a large hypothetical railyard operated by a Class I, II, or III railroad. The analysis assumes the following (For more information on the methodologies used for this analysis, scroll to the bottom of the page and click Methodology: Battery Electric Switcher Usage Pattern):

• 20 diesel switchers operate 24/7, and each switcher consumes 75,000 gallons of diesel fuel annually.
• Battery electric switchers operate 21 hours, before charging 3 hours to full battery capacity.

The results show that,

• To replace all 20 diesel switchers, 24 battery electric switchers are needed.
• Each battery electric switcher needs 2.9 MWh of usable battery capacity.
• Three chargers rated at 1.1 MW are needed at the railyard.
• The railyard requires 3.2 MW of power and 77 MWh/day of energy to support all 24 battery electric switchers.

At least one major manufacturer, Progress Rail, offers battery electric locomotives with a charging station rated at 0.7 to 1.4 MW power levels, and the manufacturer states that faster charge rates can be accommodated.

Industrial Battery Electric Switchers

The analysis calculated power and energy requirements of an industrial switcher. The analysis assumes the following (For more information on the methodologies used for this analysis, scroll to the bottom of the page and click Methodology: Battery Electric Switcher Usage Pattern):

• One diesel switcher operates one 24-hour long shift each week.
• Switchers operate a single 24-hour shift per week, before charging 12 hours to full battery capacity.
• A single battery electric switcher replaces a single diesel locomotive.

The results show that,

• The battery electric switcher needs 2.7 MWh of usable battery capacity.
• One charger rated at 250 kW is needed at the railyard.
• The railyard requires 250 kW of power and 0.4 MWh/day (or 155 MWh/year) of energy to support the battery electric switcher.

Comparison to Other Infrastructure and California Grid

Comparison to Cruise Ship Terminals

In California cruise ship terminals, shore power connection is used for hotel power while a cruise ship is at berth. While at berth, a single cruise ship uses about 5.7 MW of power, and they stay about 14.5 hours on average each visit.2  The resulting energy and power demand of a single cruise ship at berth is comparable to the battery electric switcher charging infrastructure at the example railyard. (Table 1)

Figure 2 shows satellite images of the Port of Los Angeles passenger terminal, and Union Pacific Roseville railyard that is comparable to the example railyard in the analysis. While the power and energy demand from all battery electric switchers in the railyard combined are comparable to a cruise ship docked at the passenger terminal, the railyard is roughly 53 times larger than the terminal.3  There are obviously other logistical considerations beyond the simple footprint. However, the point is that infrastructure of a similar scale has been built in several passenger terminals in California on significantly smaller footprints than railyards.

Figure 2. Satellite photo comparison of the Port of Los Angeles World Cruise Center Passenger Terminal (left) and Union Pacific Roseville Railyard (right) drawn to the same scale.

Comparison to California Grid Capacity

In 2023, switchers in California accounted for about 160,000 MWh of activity.4  Table 2 shows the breakdown of switcher activities in California in 2023. About 220,000 MWh of energy is required to charge batteries to perform 160,000 MWh of activity.5

In comparison, California in-state electric generation was 194,320 GWh in 2022.7  If all Class I switchers, Class III locomotives, and industrial locomotives transition to battery electric locomotives, electricity required to charge all of them is about 0.1 percent of California in‑state electric generation capacity.

In terms of power, even if all switchers in California are charged during the same 3-hour window every day, additional power demand to the grid during this 3-hour charging window would be 201 MW. This accounts for about 0.2 percent of the California in-state electric generation capacity in 2022.

For more information on the methodologies used for this analysis, scroll to the bottom of the page and click Methodology: Battery Electric Switcher Usage Pattern.

More Resources

CARB Zero Emission Vehicle Infrastructure Topics Page

As California makes moves to secure a cleaner future through the adoption of zero-emission vehicle technology, it must also support and educate stakeholders who need to plan for zero‑emission vehicle fleet infrastructure.

CARB is working closely with California Governor’s Office of Business and Economic Development (Go-Biz), California’s Energy Commission (CEC), other state agencies and utilities in the State to ensure this transition is a success. Investments and strategic planning are happening throughout the State.

CARB has put together weblinks intended to assist with finding funding, resources, and background Zero Emission Vehicle (ZEV) Infrastructure Topics | California Air Resources Board). Staff recommends starting with the following pages for battery electric switcher operators.

• A Zero Emission Infrastructure Joint Statement of Intent 
  • In an effort to supercharge the state’s ZEV fueling infrastructure, California announced a Joint Statement of Intent between eight state departments and agencies to help guide planning for energy supply, facilities, grid development, as well as EV chargers and hydrogen stations.
• Carl Moyer Program: Infrastructure 
  • Provides funding for the installation of infrastructure for cleaner technologies. This link provides information on program eligibility and resources to report a Moyer funded public station.
• Vehicle-Grid Integration (Advanced Clean Tech News) 
  • Provides assistance and knowledge for how to utilize the electrical grid more efficiently.

Timeline and Permits

Ports have gone through the infrastructure installation with electric utility companies with the shore power connections, and case studies and lessons learned are available in CARB and the United States Environmental Protection Agency Documents.8

Utilities and CALSTART have tools and guidebooks available for operators that outline the entire process for installing battery electric equipment charging infrastructure. These resources estimate EV infrastructures to take 3.5 to 29 months from application to completion.91011^­

Conclusion

The analysis shows that infrastructure needed for a large railyard operating battery electric switchers is similar to a shore power connection. If all battery electric switchers in California were charging from the grid, they will account for 0.1 to 0.2 percent of the California grid capacity.

In terms of power, energy, and land requirements, challenges of charging infrastructure for battery electric switchers are small compared to the current infrastructure capacity.

Combining the cooperation among state agencies, and best practices established through light duty, medium duty, and heavy duty vehicle electrification and shore power projects, challenges to locomotive charging infrastructure projects can be solved more effectively.

• 1“Shore power” refers to electrical power being provided by either the local utility or by distributed generation to a vessel at berth.
• 2(CARB, October 9, 2019. Appendix H: 2019 Update to Inventory for Ocean-Going Vessels At Berth: Methodology and Results.) 14.5 hrs per visit is average of cruise ships’ average time at berth at four California ports, Table 8. 5.7MW is average of cruise ships’ auxiliary engine effective power, Table 9.
• 3POLA World Cruise Center is about 18 acres (https://www.portoflosangeles.org/business/terminals/passenger/cruise), and UP Roseville is about 950 acres (https://ww2.arb.ca.gov/sites/default/files/2021-02/rrstudy101404_3.pdf).
• 4CARB, EMFAC2021
• 5Assuming 73% of the energy from the charger becomes the mechanical work by the switchers as described in the Separate Webpage with Details of Calculations.
• 6Class III railroads operate both switchers and regional line haul locomotives. However, the distinction is not clear, and staff included all Class III locomotives in the analysis.
• 7CEC, Electric Generation Capacity and Energy (https://www.energy.ca.gov/data-reports/energy-almanac/california-electr…)
• 8US EPA, December 2022, Shore Power Technology Assessment at U.S. Ports 2022 Update.
• 9https://crt.sce.com/overview
• 10https://www.pge.com/en_US/large-business/solar-and-vehicles/clean-vehic…
• 11https://insitetool.org/