Two Peterbilt Models Eligible for HVIP
The Peterbilt Models 520 and 320 equipped with the Cummins ISL-G Near Zero engine have been granted eligibility for the California Air Resources Board (CARB) Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project (HVIP).

Image of Peterbilt Model 320 courtesy of Peterbilt.

The Peterbilt Models 520 and 320 equipped with the Cummins ISL-G Near Zero engine have been granted eligibility for the California Air Resources Board (CARB) Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project (HVIP).
HVIP encourages the commercialization of low-emitting hybrid and zero-emissions trucks by assisting fleets with the purchase of these advanced technology vehicles.
Peterbilt introduced the Cummins Westport ISL-G Near Zero NOx emissions natural gas engine in the Models 520 and 320 in 2016. NOx emissions in the ISL-G Near Zero engine emissions are 90 percent lower than the current EPA limit.
The ISL-G Near Zero engine emissions are 90% lower than the current EPA NOx limit through the introduction of a three-way catalyst in the after-treatment, advanced engine calibration, and a closed crankcase ventilation system (CCV).
The new engine’s performance and efficiency match the current ISL-G, with 320 hp and 1,000 lb.-ft. torque available. Industries that will most benefit from the new option include linehaul, vocational, and refuse applications.
Similar to the currently available ISL-G engine, the ISL-G Near Zero operates on 100% natural gas, which can be carried on the vehicle as either compressed natural gas (CNG) or liquefied natural gas (LNG). The new ISL-G Near Zero can also run on renewable natural gas (RNG).
“Peterbilt is a leader in environmentally-friendly solutions for the industry,” said Robert Woodall, Peterbilt Assistant General Manager of Sales and Marketing. “Eligibility for the HVIP voucher will allow customers participating in the program to benefit from the advanced technology and rugged durability of the Models 520 and 320."
The 2018 Models 520 and 320 will be eligible for HVIP when spec’d with the Cummins ISL-G Near Zero engine with a GVWR of 33,000 – 80,000 pounds.
For more details, visit https://www.californiahvip.org/.
More Fuel Smarts

Cummins Adjusts 2027 Engine Rollout After EPA Proposal
The engine maker will gradually introduce its new Model Year 2027 diesel engines while continuing to offer current models during the transition, citing the EPA's proposed emissions rule changes.
Read More →
EPA Proposal Could Ease 2027 Truck Costs and Buying Uncertainty
The proposal doesn't change the tougher NOx standard, but it would revise key implementation requirements that manufacturers say have driven up costs and complicated fleet purchasing decisions.
Read More →
Cummins, Paccar Ease DEF Derates After EPA Guidance
Updated diesel engine software gives truck operators more time to address emissions-system issues while staying compliant with EPA emissions standards.
Read More →
Maintenance in the Messy Middle Part 3: Biodiesel
Biodiesel can reduce emissions, improve fuel-system lubricity and use existing diesel infrastructure. But NACFE’s Messy Middle maintenance report says fleets must actively manage storage, cold-weather operation, filters and oil drain intervals to avoid problems.
Read More →
Enhance Fleet Performance with High-Efficiency Auxiliary Power Units
Drive sustainable cost savings while increasing driver comfort during short- and long-haul logistics operations.
Read More →
Maintenance in the ‘Messy Middle’ Part 2: Renewable Diesel Fuel
NACFE's latest Messy Middle Powertrain Service & Maintenance report says renewable diesel gives fleets an opportunity to reduce carbon emissions without changing trucks, fueling infrastructure or maintenance practices. But technicians still need to understand several important operational differences.
Read More →
The Diesel Engine Enters NACFE’s ‘Messy Middle’
NACFE’s new Messy Middle Powertrain Service & Maintenance report says keeping modern diesel engines running now depends as much on software, diagnostics and data as traditional mechanical service.
Read More →
DTNA Software Update Gives Truckers More Time Before DEF Derates Take Effect
The changes reflect EPA guidance aimed at reducing downtime caused by emissions-system faults while maintaining compliance requirements.
Read More →
New Agentic Predictive Maintenance Report Demonstrates How Degraded Aftertreatment Systems Waste Fuel
Questar analyzed a large mixed-class fleet and discovered it was wasting as much as $30 in fuel per vehicle, per day, because of mechanically degraded aftertreatment systems.
Read More →
New York City's Microhub Project is Delivering Results
Trucking, last-mile delivery companies, and environmental advocates like what they are seeing so far with New York's microhub program.
Read More →
