8 JULY 2017 • FOGHORN FOGHORNFOCUS: ENVIRONMENTAL ISSUES mixtures. As a first step for vessel operators who are consid- ering biodiesel, it’s worth noting the diesel standard—ASTM D975—allows for biodiesel to be blended up to five percent and therefore is safe for use in all engines. Higher biodiesel blends, from 6-20 percent, are held to a separate quality spec- ification, ASTM D7467. B10 and B20 are the most common blends used on road and in marine applications and can be used in most engines with little or no modification. Most major engine manufacturer warrantees —including Caterpillar, Cummins, and John Deere—allow up to a B20 blend but it’s worth confirming with engine manufacturers before moving beyond B5.ASTM standards laid the ground- work to ensure consistent product was reaching the fuel rack and today, state laws requires ASTM certified product be sold in every state except Alaska. The second major improvement in biodiesel quality followed implementation of the National Biodiesel Boards’ (NBB) BQ9000 certification program. BQ9000 is a voluntary program to accredit biodiesel producers and marketers that went into effect in 2008. Now, the BQ9000 certifica- tion indicates refinement processes, storage and transport methods, and the fuel itself underwent rigorous analyses and certification by an independent auditor. To meet ASTM 6751 standards, producers must now be BQ9000 certified. At the end of 2016, over 92 percent of biodiesel produced domestically met BQ9000 standards. Most engine manufac- turers require or strongly encourage BQ9000 certification to maintain warrantees. Finally, both fuel producers and consumers have grown more sophisticated in the products they offer and demand. For instance, it is not uncommon for consumers to specify fuel characteristics, blends or additives required to meet their unique applications. To mitigate risks of cold weather gelling, or to address longer-term storage issues, biofuel users may request the addition of fuel stabilizers, biocides or additives, or request vendors modulate their fuel blend by season—such as a 20 percent blend in summer and a 5-10 percent blend during cold winter months. Most fuel suppliers are capable of and willing to meet consumer needs to ensure a positive experience with biodiesel. Why Use Biodiesel? For marine operators, using biodiesel is an effective way to reduce carbon emissions while continuing normal op- erations. “We experience less soot build-up on our vessels, reduced visible exhaust emissions, and fewer complaints from passengers about the smell of exhaust” says Brodeur. “It adds piece of mind to know 20 percent of our fuel is non-toxic and is helping King County meet its Strategic Climate Action Plan commitments. Additionally, it’s a good story to share how our use of recycled cooking oil supports local businesses and a renewable fuel industry in the Pacific Northwest.” Biodiesel is biodegradable if spilled, has a higher cetane rating than diesel, and improves lubricity when blended with diesel. Air quality benefits of using B20 compared to diesel include a 20 percent reduction in sulfur emissions and 12 percent fewer particulates and carbon monoxide emissions. While nitrous oxide (NOx) levels can be higher than diesel, engines manufactured in 2010 or later must meet specific emissions standards regardless of the fuel used and therefore NOx levels remain near zero (see Figure 1). Climate Change Benefits Biodiesel is an effective strategy for passenger vessels to reduce greenhouse gas emissions and address climate change. However, not all biodiesel is created equal. To achieve the greatest emissions reduction per dollar, consumers should look closely at biodiesel’s pathway from “well to wake” (in other words, what it’s made from and where, and how it’s transported). Evaluating a fuel’s lifecycle emissions is critical to account for the most significant parts of the fuel’s emission profile: the land use impacts, and the emissions generated during refinement and transport. When it comes to biodiesel, buying local really does make a signifi- cant difference. Biodiesel refined from second use sources, such as waste grease or used cooking oil, generally has a carbon intensity 80 percent lower than diesel fuel. However, biodiesel made from vegetable oils, particularly those asso- ciated with global deforestation or other land use impacts (palm oil and some other vegetable oils), may not reduce emissions very much or even at all compared to diesel fuel (see Figure 1). While ASTM International and the EPA may be feedstock agnostic, consumers should be discerning and choose the lowest carbon intensity biofuel available to ensure maximum environmental benefits are realized. Today, a multitude of resources exist to help fuel users make smart decisions about the alternative fuels they purchase. The National Biodiesel Board (www.nbb.org) provides a wealth of information on biodiesel best practices and trends, as does the Alternative Fuels Data Center (www.afdc.energy.gov). For information specific to your region, contact your fuel provider who can identify types of biodiesel available as well as feedstock and carbon intensity of the fuel they offer. Also, almost all coastal regions in the U.S. have a Clean Cities Coalition. The Clean Cities program is part of the U.S. Department of Energy and committed to providing resources for transportation agencies to evaluate alternative fuels and strategies to reduce their use of fossil fuels (www.cleancities.energy.gov). Finally, biodiesel is just one step toward greening your fleet. PVA’s Green WATERS program provides all the resources necessary to certify your operation and reduce your environmental impact on the water. n About the Author Alex Adams has over two decades of experience working on passenger vessels and now manages King County Department of Transportation’s Climate Change and Energy Program in Seattle WA. Alex was a presenter at the 2017 PVA Green WATERS Conference in Seattle. He can be reached at alex.adams@kingcounty.gov