Emission reductions of both GHG and NOx from Low NOx engines and renewable natural gas (RNG) “are an order of magnitude more cost effective than reductions from transition to electric or fuel cell buses,” is the conclusion of a report delivered to LA Metro in Los Angeles last week, reports Fleets&Fuels.
LA Metro is considering purchase options for the future following a decision by its Board in April to ‘develop an initial outline for a comprehensive plan to further reduce greenhouse gas emissions by gradually transitioning to a zero-emission bus fleet’. The Cummins Westport Inc. (CWI) ISL G Near Zero (NZ) offers transit authorities an alternative product that is certified to optional near-zero emissions standards and will allow LA Metro to meet its goal of zero-emission transit buses more quickly and for less money.
F&F’s editor Rich Piellisch summarises the information delivered by Dana Lowell of M.J. Bradley & Associates and Julia Lester of Ramboll/Environ for LA Metro:
- Fleet costs will rise by just 1% with LNOx+RNG, as compared to 8% to 14% for all-electric buses or 9% to 13%.
- There are significant emissions advantages: lower GHGs, lower NOx emissions
- Less expensive
The ISL G NZ engine is built off the current ISL G platform, but requires Closed Crankcase Ventilation (CCV) that prevents crankcase emissions, a larger maintenance-free Three-Way Catalyst (TWC), and a unique engine calibration. Together, these improvements will allow the ISL G NZ to certify to 0.02g/bhp-hr, or 90 percent below the current U.S. Environmental Protection Agency (EPA) NOx standards.
LA Metro, which switched entirely to CNG fuel in 2011 and reportedly operates almost 2,200 CNG buses today, will use the report to guide future technology decision-making.
Fleets&Fuels article: Vote of Confidence for LNOx+RNG