Optimal Electric Partners with Proterra for All-Electric Shuttle Bus

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Optimal Electric Vehicles, LLC (Optimal-EV) and Proterra, a leading innovator in heavy-duty electric transportation, announced a new partnership to leverage Proterra's best-in-class battery technology and charging systems for the development of the industry's first all-electric S1^LF low-floor cutaway shuttle bus for the North American market.

Optimal-EV's S1^LF will utilize Proterra's high-performance battery systems, which have industry-leading energy density for maximum range, a flexible design to fit within a wide variety of vehicles, and rigorous pack level validation to ensure safe and durable vehicle operation. The Proterra® battery system powering the S1^LF will feature 113 kWh of energy capacity and an all-electric, zero-emission drive system that is designed to enable more than 125 miles of driving range. The vehicle can fully charge in about two hours with optional DC fast charging. The all-electric S1^LF integrates a Ford E450 chassis platform, which has been fully optimized for the vehicle body. The all-electric S1^LF will feature a gross vehicle weight rating (GVWR) of 14,500 pounds, with no reduction in carrying capacity.

"Electric vehicles offer a smoother, quieter rider experience while producing zero tailpipe emissions for improved air quality and public health. Optimal is expanding the accessibility of EV technology to more riders by introducing the industry's first all-electric low-floor shuttle bus," said Optimal COO Dan Daniels. "Proterra's expertise and experience in battery-electric transit buses makes them an ideal and trusted partner as we design and deliver this new vehicle."

The S1^LF will debut at the APTA EXPO 2021, and be available for commercial purchase in 2021. The S1^LF is the first of several planned commercial electric vehicles from Optimal-EV for use in a variety of applications.

"Commercial urban fleets are an ideal use case for EV technology and we are excited to partner with Optimal to achieve a major milestone for the North American electric vehicle market," said Proterra CEO Jack Allen. "Proterra's best-in-class battery technology has been proven in more than 12 million miles of service with our transit buses across North America. Now, we look forward to providing the same industry-leading technology to power the first all-electric S1^LF low-floor shuttle bus with Optimal." Through the Proterra Powered™ program, Proterra and Optimal-EV collaborated to determine the right size, shape, and performance of the battery system for the S1^LF vehicle. Proterra Powered leverages Proterra's EV technology and expertise to help commercial vehicle manufacturers electrify their vehicles. As an OEM that uses its own battery technology to power its fleet of heavy-duty electric transit buses, Proterra brings more than a decade of experience manufacturing, testing and delivering EVs. To date, Proterra Powered has helped world-class OEMs like Thomas Built Bus, Van Hool and FCCC introduce 100% battery-electric vehicles that are powered by Proterra electric vehicle technology.

The S1^LF integrates 33 years of Optimal's automotive design and CAE (Computer Aided Engineering) optimization and validation expertise, culminating in safe, reliable and durable automotive grade products with the efficiency and performance of a factory-installed, fully integrated electric power system. Optimal's low-floor design, which is made possible by the innovative packaging of battery-electric propulsion, allows for ultra-low 11-inch step-in height and quick deployment of an ADA-compliant accessibility ramp without the need for the added complexity of a kneeling suspension. 

Engineered and manufactured in the U.S., Proterra battery packs are designed specifically for safe operation in transportation and undergo rigorous testing to ensure they can withstand the toughest conditions. Proterra batteries incorporate state-of-the-art safety features, including sensors throughout each pack that deliver continuous monitoring and diagnostics and cell-level passive propagation resistance (PPR), a safety design feature that isolates a defective cell and prevents it from causing complications throughout the entire pack. Further, each pack features a protective, ruggedized enclosure made with ballistic-grade materials.

Proterra also offers high power charging systems that are purpose-built for heavy-duty applications and use standardized technology for interoperability. Proterra charging systems utilize the universal J1772-CCS Type 1 charging standard, enabling operators to use Proterra charging systems for a range of battery-electric powered vehicles.