Emissions performance and economics are critical to making dual-fuel engines a market success
Outcomes and proceedings have been released from the Clean Fuels Consulting Critical Issues Workshop Dual-fuel(Gaseous/Diesel) Engines: Challenges, Opportunities and Strategies to Build the Market. The workshop gathered 75 natural gas and liquefied petroleum gas (LPG) stakeholders from 17 countries and four continents to evaluate the technical, economic, marketing and regulatory trends related to natural gas/LPG-diesel engines. In two-half days of presentations and discussion, the group identified possible requirements to bring these technologies to the market and identified a strategic path to help foster the development of a regulatory framework to certify dual-fuel gaseous engine systems for both original equipment manufactured (OEM) engines and retrofit applications. Participants included system designers and suppliers, OEMs, the European Commission, national government representatives, emissions experts and related stakeholders. The workshop was held in Brussels on 30-31st March 2010.
Dual-fuel systems are being developed specifically for and in conjunction with major worldwide engine manufacturers and are delivered to customers as a factory-built engine or vehicle. But regulations to enable certification of dual-fuel engines currently do not exist. In the absence of clear regulatory guidelines, some countries allow dual-fuel vehicles, some provide ‘exemptions’ on a case-by-case basis, and other countries prohibit the systems altogether. If this situation continues dual-fuel methane or LPG engines will struggle to find their legitimate place in the world markets, according to the results of the workshop, which also determined that international certification regulations must be created to facilitate worldwide markets for these technologies.
Gaseous–diesel systems have varied emissions and CO2 results, often due to the wide range of operation characteristics related to the different vehicle applications and the amount of diesel fuel that can be replaced. System suppliers identified specific emissions reductions that can be achieved over dedicated diesel engines: smoke and particulate emissions are reduced by as much as 90% and CO2 reductions in the range of 9-25%. (Dual-fuel natural gas engines, using CNG or LNG, replace up to 85-95% diesel; dual-fuel LPG engines replace about 35-40% diesel.)
Cost and economic data from active dual-fuel customers showed favorable end results. Since the profit margins of line-haul trucking tend to be relatively low – 3-10% in the cases reported – savings benefits tended to outweigh the higher initial costs of the engines and vehicles, with payback period for natural gas and LPG engines being 8 months-to-1.5 years.
Strategic Pathway
Seisler says the strategic pathway for dual-fuel engines to the worldwide market is now clear:
- The best economics of the current dual-fuel product offerings are with the heavy duty, over-the-road vehicle segment using large amounts of diesel fuel.
- Market potential of dual-fuel technologies increases significantly when the capital cost of the vehicles is reduced, vehicle and engine offerings expand, and fuelling availability is facilitated.
- Customer adoption of dual-fuel engines is more challenging than for dedicated diesel engines and vehicles due to initial uncertainty regarding engine durability, maintenance costs, operational aspects of new engines, and unfamiliarity of using different fuelling technologies and practices.
- Emissions reductions vary but will be improved with the entry of OEM engines versus some of the retrofit systems. In either case, the emissions performance must be substantiated by the system suppliers.
- Worldwide certification regulations at the United Nations (UN) for OEM and retrofit technologies will be necessary to create harmonized national certification procedures. This should significantly enhance the availability of high quality dual-fuel systems. Support for certification regulations from UN Contracting Parties (member states) and dual-fuel engine and vehicle manufacturers for both natural gas and LPG will be required to mainstream the technology.
- Future dual-fuel markets will depend upon a regulatory approach suited toward both OEM technologies and retrofit systems.
Clean Fuels Consulting’s complete Strategic Roadmap to Market Development of Certified Heavy Duty Gaseous Fuel (Methane/LPG)-Diesel Engines is available here. The Dual-fuel Workshop proceedings are available here.
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