Zero Particulate and Toxic Gas Emissions at the wharf by Commercial Hybrid-electric Powered Vessels

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1 Zero Particulate and Toxic Gas Emissions at the wharf by Commercial Hybrid-electric Powered Vessels Abstract Robert Dane, Solar Sailor Holdings Sydney Australia, Grahame Parker Grahame Parker Designs, Manfred Fahr, Solar Sailor Holdings Sydney Australia, Craig Thomsen, Enlog Systems, Sydney Australia, Bradley Patten, Enlog Systems, Sydney Australia. Exhaust from conventional internal combustion engines (ICE) s burning diesel or biofuels is discussed in relation to emissions at the wharf and the associated human health effects. This paper will for the first time discuss the absolute advantage of commercial hybrid electric vessels over conventional ICE burning diesel or biofuels. This is that commercial hybrid vessels either in series or parallel configurations including the option of use of renewable energy enable zero particulate and toxic gas emissions at the wharf. 1. Introduction The impact on both human health and our global environment from the effects of air pollution is at an all time high. 1 The transport sector s steady growth has not only contributed but is one of the major contributors to air pollution and associated health risks 2. As such, more efficient vessels and greener solutions are emerging. These include cleaner diesels, use of alternative fuels and the development of hybrid power systems. This paper will discuss the absolute advantage of commercial hybrid electric vessels over conventional internal combustion engines (ICE) s diesels and ICE s powered by biofuels. Relative advantages of hybrid electric drives compared to conventional internal combustion engine (ICE) systems are well known. These include reliability, fuel savings, passenger comfort, and lower environmental impacts. The Water Transit Authority (WTA) in San Francisco recently found emissions from diesel ferries were most significant at the wharf where the ICE is not operating at its optimum efficiency. Further this is exactly where the diesel emissions (DE) have least chance to dissipate or blow away. In particular catamarans, venting the fumes at the rear or between the hulls, cause increases in localized exposure to exhaust fumes. In order to meet standards it recommended reducing dockside idling to a minimum 3. Also in California, Proposition 65 legislation 4 lists chemicals that are known to cause human cancers. All the chemicals in diesel emissions (DE) and biodiesel emissions discussed in this paper are listed in Proposition 65. The implication for the marine industry from proposition 65 is that the correct concentration of diesel exhaust (DE) at a wharf where the particles and gases can accumulate should be zero. A commercial hybrid electric vessel has the unique ability compared to ICE powered vessels burning diesel or any hydrocarbon fuel, to switch off the ICE diesel engines and operate as an electric vessel at and near the wharf ie offering zero emissions at the wharf.

2 2. Hybrid Electric Vessels Electric and diesel/electric vessels are not new. The first electric vessels date back to the 19th century 5. Diesel-electric submarines were developed prior to World War 1 with internal combustion engines for surface cruising and charging of the batteries, and electric motors for underwater operation. Pure electric commercial vehicles are not possible with current energy storage technology as the energy in a battery is one tenth the energy of the same weight of fossil fuel 6. Hybrids have evolved by combining the efficiency and advantages of electric drive (high reliability, efficiency, lifespan and torque characteristics and low noise and vibration) with the power and range of conventional vessels. Today, series hybrid diesel/electric systems are used in luxury cruise ships and military vessels for a number of reasons including facilitation of ship design and building, passenger comfort, vibration, noise, stealth capability, redundancy and reliability. Since 2000, a commercial hybrid electric ferry has been operating in Sydney also incorporating the use of solar and wind power. Recent oil price rises have raised the general public s awareness and the automotive industry s interest in hybrid electric cars that offer conventional performance combined with significant fuel savings. Hybrid marine vessels can use at least two and in some cases multiple sources of power from which propulsion is obtained. These multiple sources of energy permit reliability through the redundancy of power and systems. Redundancy means the vessel can function in an emergency when one fuel source is unobtainable, or if one power generating component of the vessel fails. The operation and optimisation of the system is controlled by programmable software. The design of a hybrid diesel-electric system is dependant on a variety of factors, including the duty of the vessel, energy storage devices used and the use of renewable energy sources. Different applications require different types of hybrid systems. The main classes of hybrids are series hybrids and parallel hybrids. Both have the ability to be pure electric vehicles at the wharf. a. Parallel Hybrids A parallel hybrid is where both the electric motor and the engine can provide propulsion power. The two systems are in parallel i.e. completely separate with their own separate propeller/jet or joined at the propeller/jet via a gearbox or mechanical system. At low speeds the propellers/jets run on the electric motors and at high speed the vessel is driven as a conventional internal combustion engine (ICE) vessel. In a series hybrid the internal combustion engine (ICE) does not power the vessel. The ICE engine turns a generator and the generator charges the batteries or powers the electric motor that drives the propeller. All hybrid variations are able to switch off their diesel ICE and run in full electric mode at slow speed, while docking and manoeuvring.

3 Australian Journal of Mechanical Engineers Vol 4 No 2. ISSN: (2007). Figure 1-1: Example for catamaran with dual input driving single propeller Figure 1-2: Full separation of electric and diesel system. In this case there is complete physical separation of systems in separate hulls of a trimaran

4 b. Series Hybrid Figure 1-3: Hybrid power systems of series hybrid in this case the Sydney Solar Sailor 3. Diesel Emissions (DE) from Conventional Internal Combustion Engines (ICE) Conventional diesel internal combustion engines (ICE) s emit exhaust after burning or oxidising diesel, a hydrocarbon fuel. The diesel exhaust (DE) consists of fine particles and gas. Fine particles which are mostly carbon irritate human lungs and over time are known to cause emphysema, asthma and lung cancer. The gases, carbon monoxide, carbon dioxide, oxides of Nitrogen, Nitrogen compounds, Sulphur compounds, Hydrocarbons, Aldehydes, Benzene, 1,3,butadiene, Aromatic Hydrocarbons, arsenic and Nitro-PAH's (polycyclic aromatic hydrocarbons - Nitropyrene, nitrofluorene and dinitropyrene). All are known to cause lung cancer and other cancers Fine Particles in DE Diesel ICE s are a major source of fine-particle pollution. The particles are fine and highly respirable and constitute a large surface area to carry compounds into lungs. The elderly and people with emphysema, asthma, and chronic heart and lung disease are especially sensitive to

5 fine-particle pollution. Numerous studies have linked elevated particle levels in the air to increased hospital emissions, emergency room visits, asthma attacks and premature deaths among those suffering from respiratory problems. Because children s lungs and respiratory systems are still developing, they are also more susceptible than healthy adults to fine particles. Exposure to fine particles is associated with increased frequency of childhood illnesses and can also reduce lung function in children 10. Airborne particulates consist of discrete particles and are often described variously as dusts, fumes, smokes or mists depending on the nature of the particle and its size. Factors which determine the degree of hazard associated with a specific airborne particulate, namely: the type of particulate involved and its biological effect; the concentration of airborne particulates in the breathing zone of the passenger; the size of particles present in the breathing zone; and the duration of the exposure. 11 The World Health Organisation estimated that exposure to fine PM in outdoor air leads to about deaths and years of life lost each year in Europe Noxious Gases and human cancers from DE. Diesel exhaust contains many known or suspected cancer-causing substances. A study in the US showed that diesel exhaust is responsible for more than 70 percent of the cancer risk in the South Coast Air Basin in California from breathing polluted air. The contribution to risk is dominated by mobile sources (e.g., cars, trucks, trains, ships, aircraft, etc.). 13 Twice as many people died in Sydney in 2000 from air pollution than from road accidents. 14 Diesel exhaust poses a cancer risk that is 7.5 times higher than the combined risk from all other air toxins while the risk of lung cancer for people living in urban areas is three times that for those living in rural area. Adverse effects of exhaust pollutants now include increased infant mortality 15 chronic deficits in lung development of children aged years 16 acute heart attacks 17 and an association between ovarian cancer and exposure to diesel exhaust fumes. 18 Diesel exhaust is around 40 times more carcinogenic than cigarette smoke on a weight/volume basis. 19 A study conducted by the Water Transit Authority (WTA) in San Francisco 9 found that an expansion of ferry services in San Francisco will potentially lead to concentrations of nitrogen dioxide above state and federal ambient air quality standards at the San Francisco terminal. Particulate matter already exceeds the California annual PM10 and PM2.5 standards. The Air District staff s analysis indicates that the potential for localized increases in exposure to particulate matter at the San Francisco terminal could lead to a significant increase in cancer risk. The estimated existing incremental cancer risk from ferry operations at the San Francisco terminal currently exceeds the Air District s threshold for risk from exposure to diesel particulate matter. Incremental cancer risk is estimated to increase significantly in the future under both IOP idling scenarios because of the increase in ferry operations that is proposed by the WTA. It is estimated that there is not currently nor under IOP scenarios significant risk for non-cancer health problems due to exposure to diesel particulate matter. Although the WTA has already committed

6 to very-low-emission engines in future vessels, the health risk assessment suggests that additional actions and emissions controls to reduce diesel particulate may be warranted. In particular catamarans, venting the fumes at the rear or between the hulls, cause increases in localized exposure to exhaust fumes. In order to meet standards it is recommend reducing dockside idling to a minimum. Proposition 65 legislation in California 20 puts the legal onus of proof on the emitter' to prove a chemical did not cause cancer in an individual as opposed to other way round. The assumption from proposition 65 is that the correct dose of diesel exhaust (DE) at a wharf where the particles and gases can accumulate should be zero. 6. Biofuel Emissions from Internal Combustion Engines (ICE) s Biodiesel is the name for a variety of ester-based oxygenated fuels made from vegetable oils or animal fats. The concept of using vegetable oil as a fuel dates back to 1895 when Dr. Rudolf Diesel developed the first diesel engine to run on vegetable oil. Dr Diesel demonstrated his engine at the World Exhibition in Paris in 1900 using peanut oil as fuel. The use of biodiesel in a conventional ICE diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel but does not drop to zero. Table 3.1 Biodiesel Emissions Compared To Conventional Diesel 21 Biodiesel Emissions Compared To Conventional Diesel Emission Type B100 B20 Regulated Total Unburned Hydrocarbons -93% -30% Carbon Monoxide -50% -20% Particulate Matter -30% -22% NOx 13% 2% Non-Regulated Sulfates -100% -20%* PAH (Polycyclic Aromatic Hydrocarbons)** -80% -13% npah (nitrated PAH s)** -90% -50%*** Ozone potential of speciated HC -50% -10% * Estimated from B100 result ** Average reduction across all compounds measured *** 2-nitroflourine results were within test As can be seen from this table from the Australian Biodiesel Association 100% biodiesel reduces particulates, PAH Carbon Monoxide significantly but not to zero. However, it is suggested that biodiesel emissions from ICEs have the same level or more NOx or oxides of Nitrogen in emissions than diesel. 22

7 7. Conclusion Hybrid marine technology offers relative advantages of reliability, reduced fuel costs, increased passenger comfort, and reduced impact on the environment in terms of noise and pollution and greenhouse gas emissions. Uniquely hybrid marine technology offers the ability to reduce emissions at the wharf to zero. 1 Bradley, M.J., Jones, B.M. (2002): Reducing Global NO x Emissions: Developing Advanced Energy and Transportation Technologies, AMBIO: A Journal of the Human Environment, vol 31, iss 2, pp South Coast Air Quality Management District (2000): Multiple Air Toxics Exposure Study in the South Coast Air Basin (MATES-II), Chapter 7 Findings and Conclusions, p 7-1, California, March. 3 URS Corporation (2003): Environmental Impact Report, Expansion of Ferry Transit Service in the San Francisco Bay Area, p 1 Summery Findings, pp 5-8 Existing conditions. 4 State Of California Environmental Protection Agency Office Of Environmental Health Hazard Assessment, Safe Drinking Water And Toxic Enforcement Act Of 1986, Proposition 65 (2006): Chemicals Known To The State To Cause Cancer Or Reproductive Toxicity, August. 5 NJK, Electric and Solar Boat History, ( accessed 18/08/ Schainker, R.B. (2004): Executive overview: energy storage options for a sustainable energy future, Power Engineering Society General Meeting in June, IEEE, vol 2, pp US Environmental Protection Agency (EPA), (2002): Health assessment document for diesel engine exhaust, Prepared by the National Center for Environmental Assessment, Washington, DC, for the Office of Transportation and Air Quality; EPA/600/8-90/057F. National Technical Information Service, Springfield, VA; PB Michigan Department of Consumer and Industry Services Bureau of Safety and Regulation (2006): BSR/CET-970, vol 2, pp US Environmental Protection Agency, National Centre for Environment Assessment, Washington Office (1998): Carcinogenic Effects of Benzene - an update, EPA, vol 600, pp California Environmental Protection Agency s Office of Environmental Health Hazard Assessment (OEHHA) (1998): Comprehensive health assessment of diesel exhaust. 11 Australian Government: Department of Employment and Workplace Relations, Airborne Particulates, ( accessed 07/08/ World Health Organisation (2004): Systematic Review Of Health Aspects Of Air Pollution In Europe, (E83080), p South Coast Air Quality Management District (2000): Multiple Air Toxics Exposure Study in the South Coast Air Basin (MATES-II), Chapter 7 Findings and Conclusions, page 7-1, California, March. 14 Australian Bureau of Transport and Regional Economics ( Report, September Gosline, A., (2004): Air Pollution Damages DNA Long Before Birth, New Scientist, 3 July. 16 Gauderman, J.W. and others (2004): The Effect of Air Pollution on Lung Development from 10 to 18 Years of Age, New England Journal of Medicine, 9 September. 17 Annette Peters and others (2204): Exposure to Traffic and the Onset of Myocardial Infarction, New England Journal of Medicine 21 October 2004, Volume 351: , No 17, p 1721

8 18 Guo, J. (2004): Risk of Esophageal, Ovarian, Testicular, Kidney and Bladder Cancers and Leukemia Among Finnish Workers Exposed to Diesel or Gasoline Engine Exhausts, International Journal of Cancer, 20 August. 19 Gong and Waring, SAE Australia, May/June State Of California Environmental Protection Agency Office Of Environmental Health Hazard Assessment, Safe Drinking Water And Toxic Enforcement Act Of 1986, Proposition 65 (2006): Chemicals Known To The State To Cause Cancer Or Reproductive Toxicity, 11 August. 21 Australian Biodiesel Association 22 Society for Engineering in Agricultural, food and biological systems (2002): Physical Properties and Composition Detection of Biodiesel-diesel Fuel Blends, ASAE Meeting presentation in July, Tat, M.E., van Gerpen, G.H. (paper ), p 9.