Lawnmower, two-stroke petrol, Victa Mustang Mulch 'n' Catch with Eco Torque two-stroke engine, plastic / metal / rubber, designed and made by Victa Lawncare Pty Ltd, Australia, 2007
This lawnmower with the new Eco Torque two-stroke engine is the first attempt by Victa to address engine emissions in the design and marketing of their mowers. With this mower the company has made a small change to the existing engine technology to achieve emission reductions while maintaining its cultural meaning as a robust and reliable mower.
The new engine is the result of several years research and technical development by Victa and UTS in response to government pressure to reduce small engine emissions and improve urban air quality. It represents the complex relationships between government, industry, technology and culture in achieving environmental outcomes.
Through simple modifications to the engine block, carburettor and muffler, harmful emissions (carbon monoxide, hydrocarbons, and oxides of nitrogen) have been reduced by 30% and fuel consumption by 20%. While this engine does not yet meet strict US regulations Victa is continuing its research and development to further reduce emissions and meet equivalent regulations which may be introduced in Australia in the future. This Eco Torque two-stroke engine and mower will potentially become rare once these regulations are introduced in Australia.
The Victa lawnmower and the system of lawns and horticulture of which it is part are facing some social and environmental challenges. Restrictions on water use and government policies of urban consolidation are putting pressure on the very survival of lawns. This mower with Eco Torque engine is an example of design to address environmental concerns in the lawn care industry.
This mower was assembled in 2007 at the Victa assembly line at Moorebank from components manufactured elsewhere. Approximately 90% of the components were manufactured in Australia. The Eco Torque two-stroke engine was manufactured by Century in Adelaide, South Australia for Victa.
The new Eco Torque engine is the outcome of a four-year research collaboration between Victa and the University of Technology, Sydney. The project was funded by an Australian Research Council grant from 2003-2005. The Eco Torque engine reduces harmful emissions (carbon monoxide, hydrocarbons, and oxides of nitrogen) by 30%, fuel consumption by 20% and increases torque by 5% compared to the earlier Victa 2-stroke engine.
The main design changes were to modify the block, carburettor and muffler. The position of the inlet and exhaust ports on the engine block were modified. The carburettor jet and shape of the nozzle were changed to improve the atomization of the fuel. And the central baffle of the muffler had the restriction increased by adding restriction plates. These changes were already known in the scientific literature but the challenge was to combine all three into a practical, cost effective engine. The development project combined three strands of work carried out by UTS into one project. CFD (Computational Fluid Dynamics) modelling was used in the development of the engine. Key people involved in the technical development were Associate Professor Guang Hong from UTS Faculty of Engineering and Julia Prudhoe Technical Manager from Victa.
The design of the Mustang mower deck, engine cover and catcher originates with the Razor model designed and developed by Victa with Blue Sky Creative in 2002-2003.
This mower was donated to the Museum by Victa at the launch of the Eco Torque engine at the Powerhouse Museum on Wednesday 24th January 2007. It was used at the launch and operated briefly for recording by the media. The Eco Torque engine will initially be available on the Mustang mower from February 2007 and introduced progressively on all Victa two-stroke models by Spring 2007.
Until recently Australian emission control strategies have been focused on the major polluters of industry and motor vehicle engines. Consequently, emission reduction technologies for lawnmowers and other gardening implements have not been a design consideration. As a result the emissions from an unregulated small engine can contribute more emissions per hour of use than a much larger car engine which has emissions control technology.
Domestic lawn mowing accounts for 10% of the total anthropogenic volatile organic compounds (VOCs) in the Greater Sydney Metropolitan region on a summer time weekend. VOCs contribute to ozone and smog formation in summer. Because of the combustion of oil, lawnmowers also emit high levels of particles. The National Pollutant Inventory (NPI) indicates that lawnmowers produce air toxics and are responsible for over 9% of benzene emissions in the Greater Sydney Airshed. In some areas of the US, the contribution of lawn mowers to total hydrocarbon emissions was found to be as high as 13%.
The US has led the world in regulating emissions from small engines, beginning with the introduction of Phase 1 regulations in 1997. After a failed negotiation process the US EPA introduced Phase 2 standards in 1999 which are due to be implemented by August 2007 and will see the two-stroke engine effectively banned. The standard for small lawnmower engines is 16.1g of combined emissions of hydrocarbons (HC) and oxides of nitrogen (NOx) per kW per hour of operation. Following a three year political dispute, reluctance from US engine manufacturers and a technical investigation by the US EPA the state of California introduced a third phase of legislation in 2006 requiring the use of catalytic converters to further reduce emissions from January 2007. The US EPA is considering implementing the Phase 3 standards nationally. Europe has introduced standards based on the US EPA.
Since 2004 the NSW Government has been investigating measures to encourage the adoption of less polluting small engines by influencing manufacturers and importers to supply cleaner products and informing and influencing consumers to purchase cleaner small engines. By 2006 the emissions from small engines had become a national issue and the Commonwealth Department of Environment and Heritage is due to release a scoping report following consultation with the states and industry in early 2007. The introduction of Australian standards are generally supported by industry and if introduced would most likely reflect the US EPA standards.
In June 2008 parent company GUD sold Victa to US firm Briggs and Stratton, which had been a supplier of engines to Victa for many years. Reasons cited included uncertainties in weather conditions and their impact on the market, and competition from international manufacturers.
Priest M, Williams D and Bridgman H (2000), Emissions from in-use lawn-mowers in Australia, Atmospheric Environment, Vol 34, p 657-664.
NPI (2004), NPI Database - Benzene Summary [online], Australian Government Department of Environment and Heritage, available from http://www.npi.gov.au, [23 August 2004].
Department of the Environment and Water Resources (2007), Comparative Assessment of the Environmental Performance of Small Engines - Outdoor Garden Equipment, Prepared for Department of the Environment and Water Resources, Environment Link and Vehicle Design and Research P/L, February 2007, available from
http://www.environment.gov.au/atmosphere/airquality/publications/pubs/outdoor-garden-equipment.pdf [November 2007].