By Grey Lee
It's always difficult getting folks to break out of their routine and embrace a better way of doing things. This is even more true when you propose a more environmentally sound way of doing things. The innovation may be a bit easier to adopt if it came with benefits such as lower costs, less maintenance, a better user experience, and demonstrable environmental benefits.
The opportunity is sweetened further if it comes with some free money.
This is exactly the case with switching from gas powered outdoor maintenance equipment to propane power and it can be done with significant grants to offset the initial costs. These grants are available from the Propane Education and Research Council. They provide for up to $500 to convert a gas powered commercial mower to propane and up to a $1,000 rebate for the purchase of new propane powered mower. More info can be found here.
Why would somebody want to do this? After all, you are just swapping one fossil fuel for another. This seems true, but anyone pursuing LEED-EBOM will be putting together a forward looking landscape maintenance plan and it is also important for the SITES certification. LEED v4 specifically offers credits for site management plans that adopt gasoline free and low emission landscaping. The idea also makes sense from both a fiscal and a sustainability perspective.
All groundskeepers, whether on a commercial campus or a public park/school, are concerned about ever-shrinking budgets. Converting to propane based equipment can help; the cost per gallon equivalent is between 30% and 50% less because, unlike gasoline, it is easier to negotiate a contract price for a full year. Secondly, the maintenance interval for propane equipment is much longer; many people see oil changes move from every 25 hours to every 100 hours. Third, The equipment lifespan is frequently increased. Commercial mowers typically need to be rebuilt or replaced at about 2,500 hours. Propane powered equipment can see a 50% improvement due to cleaner oil and pistons. Finally, the loss of fuel due to theft and spillage is virtually eliminated.
Reducing environmental impact
Spillage of gasoline is an often overlooked environmental problem. The EPA estimates that 17 million gallons of gasoline are spilled annually when fueling landscaping equipment. The lack of spilled fuel is just one of many environmental benefits. According to the EPA, about 5% of ALL air pollution is generated by lawn care equipment. Propane powered equipment can help with this problem. Propane yields more than a 25% reduction in green house gasses versus gasoline. It reduces carbon monoxide emissions by greater than 60%, generating fewer ground level ozone precursors and fine particulates than conventional gasoline powered equipment. Conversion kits are certified by both the EPA and the very strict California Air Resources Board (CARB). Most jurisdictions even allow for the use of propane powered equipment during ozone action days when ground level ozone concentrations force the shut down of gasoline powered small engines.
Similar performance to gasoline
A question often asked is, “The benefits are obvious, but how does it perform?”. The market itself is beginning to answer that question. Many major landscaping outfits, particularly in the south and west where they are often subject to ozone action shutdowns, are switching to propane. They claim that they have the same power with all the benefits. Operators like it because it can be quieter and they are exposed to less fumes. One issue that I have uncovered is that propane is somewhat less energy dense than gasoline. This results in the range of a tank of propane being equal to about 3/4 of that of a comparable gasoline tank. The issue of fuel transfer can also be an issue. Large operators will benefit from an on-site tank filling infrastructure, but this is a large upfront expense. These costs can often be offset by grants and rebates, which are worth pursuing. Smaller operations can have a dedicated tank exchange installed, similar to those seen at supermarkets or hardware stores.
One advantage to investing in a propane filling station is that it allows for the future expansion into vehicles. I have driven propane and natural gas vehicles and have found them to be identical in performance to gasoline. Having a fueling station would allow for large vehicles to be converted to propane. The lack of a wide array of fueling stations limits a vehicles use, but operating out of a central location that is equipped with a fueling station makes sense.
A reasonable alternative
Electric powered equipment would be the best choice. They could be powered via alternative means and would emit next to nothing in hazardous air pollutants. There are several viable electric options available for smaller pieces of equipment (blowers, trimmers, saws etc.), but electric still does not have the range or power needed for larger pieces of machinery. However, propane can power smaller engines such as blowers, both large and smaller ones. One of the best solutions I have seen is a solar array that powers a battery recharging station with interchangeable batteries for the smaller pieces of equipment and propane for the higher power equipment. This could be a bridge solution that is enhanced by the prospect of free money.
Kevin Dufour is an Environmental Scientist with Viridis Advisors. He collaborates with Tom Irwin on creating greener greenscapes.