In the United States (US), Aemetis, Inc., a renewable natural gas (RNG) and renewable fuels company focused on negative carbon intensity products, and the American Power Group Inc., a subsidiary of American Power Group Corporation (APG) have demonstrated the patented “Turbocharged Natural Gas Dual Fuel System” for truck engines to multiple truck fleet owners and operators who transport biofuels, animal feed, and other agricultural products for Aemetis and other businesses in the California region.
Founded in 2009, American Power Group (APG) has developed the patented dual fuel technology to simultaneously combust two fuels, natural gas, and diesel fuel, to power a diesel engine.
The technology allows a turbo-diesel engine to operate on up to 65 percent natural gas or renewable natural gas (RNG) and 35 percent diesel, including renewable diesel. The technology is already operating in more than 3 000 stationary engines and 1 000 trucks worldwide, complying with the US Environmental Protection Agency’s (EPA) Clean Alternative Fuel Vehicle Conversion regulations.
Lower emissions and fuel cost
A truck operated using Aemetis locally produced, dairy RNG and renewable diesel or biodiesel would be carbon negative, low emission, and lower cost than diesel.
The system maintains the power of a 100 percent diesel engine while using less than half as much diesel fuel, leading to significantly fewer emissions.
Annual fuel savings from using RNG to replace up to 65 percent of diesel fuel have been shown to exceed US$30 000 per truck per year, depending upon the respective cost of the fuel sources.
Dairy RNG is usually US$2.00 to US$3.00 per Diesel Gallon Equivalent (DGE) less expensive than petroleum diesel. Retrofit costs are about US$10 000 plus the cost of an onboard natural gas tank.
This patented technology replaces up to 65 percent of the fuel used by a turbodiesel truck with renewable natural gas at only about a US$25 000 cost of conversion that takes less than one day to complete. By using Aemetis dairy RNG, waste material is powering the replacement of diesel which significantly reduces emissions, said Chuck Coppa, CEO of APG.
The system adds natural gas tanks to a Class 8 diesel tractor and uses software to manage the two fuels, saving money at the pump while reducing emissions. The dual fuel system is fully automated, eliminating the need for operator intervention.
APG created a digital design to safely introduce natural gas into the air induction system before the turbocharger spins up – in essence, turbocharging air already going to the engine.
The spinning air reaches the compression chamber to create higher energy at the point of combustion.
These dual fuel systems represent an important transition step in California’s evolution to cleaner air and ultimately net-zero carbon emissions, said Eric McAfee, Chairman, and CEO of Aemetis.
Earlier this week, the technology was demonstrated to regulatory agencies and policymakers in Sacramento.
Currently, the heavy-duty vehicle fleet in California is still more than 98 percent diesel-powered. The low-cost conversion of existing diesel trucks will drive the adoption of reduced cost, lower emission fuels such as dairy-generated RNG, Eric McAfee added.
