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The Tao of Mow   arrow

By: Cary Weiner; 4/26/2017

Grass growing – and mowing – season has arrived, at least here on the northern Colorado Front Range. And with that comes the pesky question of how to mow efficiently and effectively. While gas-powered and corded (electric) mower technology has remained fairly static, cordless (battery-powered) mower technology seems to grow with each coming of the spring.

Plenty of articles have discussed the pros and cons of gas, corded, and cordless mowers from a performance standpoint. To summarize, cordless mowers are quiet and emission-free (on-site), but are best for smaller lots with manageable grass to avoid excess time spent recharging batteries. Corded mowers don’t pollute at the source, are quiet, and cost less than their cordless counterparts. They also avoid concerns about recharging and can handle tougher grass conditions, but cords must be managed properly throughout the mow and even extension cords limit their reach. Gas mowers provide tons of power and can go anywhere, but pollute, are noisy, and require the most maintenance.

But you knew all that already. What’s harder to pin down is a good apples-to-apples comparison of financial and environmental operating costs. Let’s compare some “typical” units of each kind, noting that advances in battery technology have allowed for recharges in as little as 1 hour.

 

 

 

 

 

 

Assumptions:

  • 10 cents/kilowatt-hour for electricity
  • $2.50/gallon for gas
  • ½ acre cut per charge and per tank
  • Corded mower cuts 1.5 times as fast as the cordless
  • Mow ½ acre 12 times per year
  • Typical gas: 4 horsepower, 0.25 gallon capacity gas

While these differences may seem like penny- (or emissions-) pinching, they add up quickly when considering that there are 2 million homes in Colorado. The difference between all homes using typical gas mowers versus the cordless mower in the example equates to almost 54,000 tons of CO2, or the emissions of close to 11,500 passenger cars (U.S. EPA). And in addition to CO2, most gas mowers emit smog-forming hydrocarbons and particulate matter that can have adverse impacts on human health.

All this isn’t to say that one should never use a gas mower. For most people, their mower choice will balance practicality, cost, and environmental benefits. Plus, gas mowers can be used in early mornings, late afternoons, or not at all on high ozone days to minimize the effect of pollutants. We just hope we’ve provided the information you need to achieve your personal balance – the Tao of Mow.

P.S. Shout out to manual push (reel) mowers, which avoid any emissions altogether and are totally free to operate (except for an occasional sharpening)!