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As Electric Buses Scale, Composite Bus Production Adds To American Manufacturing Jobs

As Electric Buses Scale, Composite Bus Production Adds To American Manufacturing Jobs

On Thursday, April 25, representatives from Proterra, TPI Composites, Des Moines Area Rapid Transit (DART) and General Electric gathered with Iowa state officials to celebrate Iowa’s 100% clean transportation journey at TPI’s factory in Newton, Iowa. At the factory, TPI manufactures composite wind blades for the wind energy market and manufactures Proterra’s pioneering composite bus body for its North American customers. With more than 1,000 associates at the Newton factory, TPI is proud to be a “made in America” company, adding to Proterra’s own US manufacturing locations.

“We are here to celebrate the TPI Composites plant in Newton, Iowa and to recognize Iowa’s leadership in wind energy and clean transportation,” said Governor Kim Reynolds. “This plant is a remarkable example of innovative partners working towards sound, sustainable practices, while providing local jobs and clean energy transportation, a win-win for the state of Iowa.”

With our industry-leading bus design, including the lightweight composite body, most energy dense batteries, highly efficient electric drivetrain technology, and connected vehicle intelligence system, Proterra has helped North American transit agencies, airports and universities lead the transition to zero-emission electric buses. DART, the largest public transit agency in Iowa, will soon be the first transit agency in Iowa to deploy zero-emission buses, bringing clean, quiet transportation to the greater Des Moines area.

“Investing in clean technology means creating jobs and bringing the next wave of innovation directly to communities across the U.S.,” said DART CEO Elizabeth Presutti. “DART will be the first in Iowa to have Proterra electric buses, and it’s a special opportunity to have the bus bodies made in our home state.”

TPI opened its plant in Newton in 2008 to build wind turbine blades. The plant found a natural home in Newton, as Iowa continues to be a wind energy leader with about 34 percent of its electricity coming from wind in 2018. TPI and Proterra formed a partnership, as Proterra was looking to design and manufacture a new transit bus that would support electric vehicle technology and be lightweight, durable and safe, and designed for best battery placement beneath the vehicle, between the two axles. TPI uses similar carbon fiber-reinforced composite material to build the Proterra bus bodies as well as its industry-leading wind blades. In addition to its Rhode Island factory, TPI began building Proterra bus bodies at its Newton factory last year to support the growing customer demand.

“We are thrilled to have opened our second Newton plant to build composite bus bodies for Proterra. Proterra is providing U.S. transit authorities, such as DART, with 100% electric buses in a cost-effective manner,” said Steve Lockard, President and CEO, TPI Composites. “This is what 100 percent clean transportation looks like – combining cost effective wind energy, solar energy, battery storage, transmission and electric vehicles.”

Instead of retrofitting diesel buses, Proterra designed a purpose-built bus to be electric and enable energy-dense battery systems to be located safely beneath the floor of the bus and outside the passenger compartment, with the option for additional battery packs on the roof. This distinct design creates a low center of gravity and allows more energy to be stored on board for increased range. Proterra’s composite bus body is central to this design and was envisioned, prototyped, tested and developed by veteran materials engineers with more than two decades of experience in the automotive industry.

Unlike steel bus frames, which experience significant corrosion throughout their 12-year life-span, Proterra’s composite bus body is impact- and corrosion-resistant, prolonging its useful life by many years. The Proterra bus body is also much lighter than its steel counterparts, enabling the Proterra Catalyst® vehicle to be the lightest-weight electric bus in its class. The unique, carbon-fiber-reinforced composite material maximizes vehicle performance and life while minimizing repairs and maintenance. A high power-to-weight ratio contributes to the best acceleration in the transit bus market—from zero to 20 mph in less than seven seconds with the ProDrive drivetrain, and less than 5 seconds with the DuoPower drivetrain.

“The lightweight composite material we use to build our battery-electric buses removes 4,000 pounds of weight compared to a metal bus frame and chassis, which allows us to store more energy on board to increase the range of the bus and meet the daily route needs of transit agencies,” said Proterra CEO Ryan Popple. “Having a composite body is what helped us exceed the world record for longest distance driven by an electric vehicle on a single charge – 1,101.2 miles with 660 kWh of energy storage.”

Proterra is proud to be the only U.S. manufacturer of purpose-built heavy-duty electric buses. Proterra has its headquarters and battery manufacturing facility in Burlingame, CA., and has its bus manufacturing factories in Los Angeles County and Greenville, South Carolina.

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