written by
William C. Vantuono, Editor-in-Chief
San Joaquin Corridor and Capitol in Emeryville, California Photo: Pi.1415926535/Wikipedia
Renewable diesel (RD), a locomotive fuel made from renewable feedstocks and considered more sustainable than its fossil fuel counterpart, will soon be deployed on two intercity passenger rail services in California.
On May 8, when a storage tank is expected to be delivered to the Oakland maintenance facility, Corridor of the Capitol i San Joaquins locomotives will begin the transition to RD. The goal is to have the entire fleet in DR by the end of the month.
The Capitol Corridor Joint Powers Authority (CCJPA) began exploring alternative fuel options in partnership with the California Air Resources Board (CARB). The California State Transportation Agency (CalSTA) “stepped up to fund testing and worked with passenger rail equipment manufacturers to ensure the effectiveness of the new fuel source,” said Robert Padgette, CEO of CCJPA. CalSTA also worked with the US Environmental Protection Agency (EPA) to obtain certification.
CCJPJ President Robert Raburn noted that the project “was a collaborative effort of partners across the state committed to advancing California’s zero emissions goal.” Raburn added.
CCJPA worked with Amtrak, RD Western States Oil’s fuel distribution contractor, and Neste, the world’s largest RD producer, to successfully complete testing of Neste MY Renewable Diesel™ in August 2022. RD Certification followed in November 2022. Neste MY Renewable Diesel “is fully compatible with all diesel engines and current diesel distribution infrastructure, so the Capitol Corridor required no additional investment or modification to make the switch,” pointed out the CCPJ. “Made from sustainably sourced and 100% renewable raw materials, Neste MY Renewable Diesel ™ can reduce up to 75% of GHG emissions over its life cycle compared to fossil diesel.”
According to Neste, the GHG emission reduction varies depending on the region-specific legislation that provides the methodology for the calculations (eg EU RED II 2018/2001/EU for Europe and US California LCFS for the US) , and the mix of raw materials used. to manufacture the product for each market.
Transitioning to a more sustainable fuel aims to reduce a fleet’s environmental impact, but requires technical expertise, funding and regional and federal oversight. The US EPA has strict standards that reduce PM (particulate matter) and other harmful emissions from locomotive engines (the current standard for new locomotives is Tier 4), as well as by fuel type. The Capitol Corridor and San Joaquin services, the latter operated by Amtrak California for the San Joaquin Joint Powers Authority (SJJPA), share a locomotive fleet consisting of EMD F59PHIs, Siemens Chargers equipped with Cummins Tier 4 QSK95 diesel engines and Wabtec (previously). GE) P32-8WHs.
“Moving to RD has been a strategic initiative for the San Joaquins,” said Brian Schmidt, SJJPA Director of Equipment Services. “SJJPA would like to thank CCJPA for their leadership in converting our shared fleet to renewable diesel. Our collective commitment to reducing greenhouse gas emissions has taken a big step forward.”
“As we implement our Climate Commitment, we welcome new ways to support Amtrak trains in California, including the 170-mile Capitol Corridor route,” said Amtrak Vice President Jeanne Cantu in California “We are thrilled that the success of the pilot will allow us to operate on renewable diesel, resulting in lower life-cycle emissions in California.”
RD is chemically similar to crude oil-based diesel, but is made from renewable feedstocks such as used cooking oil and animal fat byproducts. It differs from biodiesel, which is made, for example, from soybeans. “Because RD is produced using already existing carbon stored in renewable feedstocks in nature, when the fuel is burned, the carbon dioxide it emits is not considered to be adding new carbon to the atmosphere,” said the CCPJ. “The use of fossil diesel, on the other hand, releases carbon dioxide and other greenhouse gases, contributing to climate change. Other emissions, such as fine particulate matter and nitrogen oxides, can also be reduced with renewable diesel, which improves local air quality.”
FAME (fatty acid methyl ester) is the generic chemical term for diesel fuel derived from renewable sources. It is used to supplement or replace the mineral diesel and gas oil used to power on-road and off-road vehicles and static engines. FAME consists of acids created during the transesterification of vegetable oils and animal fats to create biodiesel. These high molecular weight oils and fats react with the short chain alcohol in the presence of a catalyst, usually potassium hydroxide, to produce lower molecular weight esters.
Wabtec (which currently does not offer passenger locomotives) has more than 40 freight units operating on different fuel mixes, for example 20% biodiesel and 80% renewable diesel. “Biodiesel is close to diesel, but with more waxes and paraffins and other elements,” Wabtec executive vice president and chief technology officer Eric Gebhardt explained in a recent It was the railway era article on alternative locomotive power. “It’s chemically different. Renewable diesel is hydrogenated, so it’s a pure form of the diesel molecule. It’s actually a little too pure, so it requires additives to improve viscosity. We’ve approved up to a 5 % biodiesel and up to 30% renewable diesel for our locomotives, and we are trying to get to 20% biodiesel and up to 100% renewable diesel. Both types come from the same feedstock. We have to ‘understand what parts of the engine would have to be changed to burn these different types of fuels, such as hoses and seals. We want to understand the deterioration factors, the impact on fuel injection systems, for example, to maintain- us within the current emissions compliance standards. The fuel injectors have very precise steps. We have to make sure we can meet the NOx and particulate requirements.
“We’re working with our customers through field testing, inspecting these units to make sure we know what the maintenance intervals should be. We care less about (domestic) metals. We don’t think either of these would be a big concern, with the right additives of lubricity (the measure of friction reduction) and viscosity (the measure of a fluid’s resistance to flow). We’re paying a lot of attention to how the elastomers and hoses, the rubber components, will interact. We have a program with Class I, and we see no reason why we can’t be successful with that. In the long term, it will be important for our customers to understand the availability and cost of these fuels. Some parts of the US have significant subsidies, California for example. Prices may vary in different parts of the US.”
