Southwest Research Institute has unveiled a groundbreaking medium-duty truck that pairs a natural gas engine with a hybrid system, achieving an impressive 25% cut in greenhouse gas emissions over traditional diesel trucks.
This project represents a significant leap forward in natural gas vehicle technology, thanks to a collaborative effort with Isuzu Motors, Woodward Inc., and the South Coast Air Quality Management District. It benchmarks an existing diesel truck to set goals for improved fuel efficiency and reduced carbon emissions.
The initiative focused on creating a hybrid powertrain that optimizes natural gas, balancing environmental benefits with fuel efficiency, cost-effectiveness, and enhanced air quality. Ryan Williams, who leads SwRI's spark-ignited engine division, discussed the limitations of converting diesel engines to natural gas. The project instead developed an engine based on modern gasoline designs, customized for natural gas to elevate combustion efficiency markedly.
Featuring a "P2" hybrid setup, the truck includes a 100 kW electric motor and a 40 kWh battery, positioned between the engine and transmission. This configuration supports electric, gas, or hybrid operation modes, allowing for optimal performance across different driving conditions.
Williams highlighted the system's ability to match diesel performance while reducing CO2 emissions by 12%, attributed to natural gas's lower carbon content. The hybrid model further diminishes CO2 emissions, especially beneficial in stop-and-go urban traffic, by enabling the engine to shut off under certain conditions.
The project also aimed at slashing nitrogen oxide (NOx) emissions, crucial for meeting stringent future regulations. Expected to tighten to an 80-90% reduction in NOx by 2027, the truck's technology, using a standard three-way catalyst, already meets these forthcoming standards, achieving emission levels as low as 0.02 g/hp-hr, thus setting a new benchmark for eco-friendly transportation solutions.