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Help Is On the Way In the War Against Noisy Leaf Blowers
HughPickens.com writes: Perry Stein writes in the Washington Post that the fight against noisy leaf blowers is gaining momentum, in part, because residents are framing it as a public health issue. Two-stroke engine leaf blowers mix fuel with oil and don't undergo a complete combustion, emitting a number of toxins, like carbon monoxide and nitrous oxide, which their operators inevitably inhale. Municipalities throughout the country have moved to ban them. "You find two-stroke engines in poorer countries because they're cheap," says James Fallows citing a 2004 National Institutes of Health study showing that two-stroke engines on two- and three-wheeled vehicles in Delhi, India, account for a significant amount of air pollution. "You don't find them in richer countries because they're so dirty and polluting." In Washington DC leaf blowers can't exceed 70 decibels as measured from 50 feet away. (A normal conversation is typically about 60 decibels.) Haskell Small, a composer and concert pianist who is helping to lead the leaf-blower battle in Wesley Heights, describes the sound as "piercing." "When I try to compose or write a letter, there is no way for me to listen to my inner voice, and the leaf blower blanks out all the harmonic combinations."
But help is on the way. A new generation of leaf blowers is more environmentally friendly as the emergence of battery-powered leaf blowers takes us closer to the Holy Grail of equipment that is both (1) powerful and (2) quiet. Fallows supports the notion of a kind of trade-in program, where loud, old leaf blowers are exchanged for the less offensive kind. Ted Rueter, founder of Noise Free America, facilitated one such scheme. In the heat of his front lawn dispute with his neighbor, he offered a solution. "If you agree to use them, I will buy you two new leaf blowers," Rueter told his neighbor. "The offer was accepted and the noise level in his front yard was restored to a peaceful level," says Lawrence Richards. "When it comes to the balancing act of protecting landscaping jobs while reducing noise and emissions, it helps that someone was willing to pay for progress."
But help is on the way. A new generation of leaf blowers is more environmentally friendly as the emergence of battery-powered leaf blowers takes us closer to the Holy Grail of equipment that is both (1) powerful and (2) quiet. Fallows supports the notion of a kind of trade-in program, where loud, old leaf blowers are exchanged for the less offensive kind. Ted Rueter, founder of Noise Free America, facilitated one such scheme. In the heat of his front lawn dispute with his neighbor, he offered a solution. "If you agree to use them, I will buy you two new leaf blowers," Rueter told his neighbor. "The offer was accepted and the noise level in his front yard was restored to a peaceful level," says Lawrence Richards. "When it comes to the balancing act of protecting landscaping jobs while reducing noise and emissions, it helps that someone was willing to pay for progress."
First World Problems.
"You find two-stroke engines in poorer countries because they're cheap,"
No, you find two-stroke engines in applications where you need high power but extremely low weight. Their cheapness is simply a byproduct of their simplicity (hence, weight savings). There are plenty of applications where a 4-stroke engine simply wouldn't work because it would weigh too much (leaf blowers, chain saws, etc) or would be too bulky (mopeds, model airplanes, lawnmowers, etc). Sure their efficiency needs some work, or replacement if a viable alternative is created, but at the moment there are several applications where 4-stroke engines or battery power simply wouldn't work.
...the emergence of battery-powered leaf blowers takes us closer to the Holy Grail of equipment that is both (1) powerful and (2) quiet....
and (3) runs for only 10 minutes before the battery drains down.
.
True, the weaker battery-operated leaf blowers can have battery run time that is beyond 10 minutes. However, if you're looking for a battery-operated leaf blower that as powerful as one with a two-cycle engine, then you're looking at leaf blowers with a useful battery life of around 10 to 15 minutes.
Note: when the manufacturers rate the battery run time of leaf blowers in their advertisements and on their websites, they usually rate the battery life with the leaf blower running on its lowest speed. That's how they can say the battery lasts for an hour or more.
If you're just looking to blow the leaves off your patio or sidewalks, then the battery operated ones are fine. But don't expect to clean any reasonable sized yard of leaves..
This is part of the same general trend as battery technology gets better: we don't need fossil fuels for nearly as many things as we did previously. To some extent this one is a bit of a no-brainer, because leafblowers are not technologies where one has to worry terribly about being stranded if there's no nearby recharge station or if the range isn't far enough (which helped hold back electric cars). It will be interesting to see how far this goes. Some optimists (such a Elon Musk) think that we'll eventually have boats and airplanes which use batteries, thus relegating fossil fuel use to essentially some rockets which require the very high energy density, plastic and other petrochemical derivative production (which will take a lot longer to find alternatives for), and energy in the grid. Note by the way that because large generators like power plants are more efficient than small ones, as long as one has decent batteries and doesn't have terrible power plants on the grid, that's still a net gain.
However, I'm pessimistic about this sort of trend for a few reasons. First, many countries are still producing coal power plants, and although a natural gas or oil plant is often cleaner than a car or other device burning gasoline, this is often not the case for coal plants. In some developed countries, like the US, the total percentage of power produced by coal is going down but the total amount of coal production is roughly constant and projected to remain so for at least a few decades https://en.wikipedia.org/wiki/Electricity_sector_of_the_United_States. While newer coal plants are more efficient and cleaner, this is only by a comparatively small degree. Of course, if do eventually get cheaper nuclear (such as with more modern reactors or maybe even with thorium reactors) this situation may change- right now the fact that nuclear is held to much higher safety standards than fossil fuel plants is a large part of its very high cost.
More seriously for the very long-term hope of making batteries handle all transport technologies including ships and airplanes, it isn't clear that battery technology will improve that much over time. The primary thing that matters is energy density, which has two forms, energy per mass and energy per volume. https://en.wikipedia.org/wiki/Energy_density Both need to be much better than they are today for electric airplanes to have any chance (lifespan and and number of cycle uses also need to improve but that's in some ways less of a barrier.) Energy density of batteries by both metrics batteries has increased by 5%-10% a year depending on the exact metric and choice of examples https://www.quora.com/Is-it-true-that-battery-energy-density-improves-5-8-per-year which is exponential growth ( but with a much slower doubling time than something like Moore's Law. One has a doubling about once every 8 or 10 years.) Jet fuel has an energy density of around 45 MJ/kg, The most efficient batteries have a little under 1 MJ/kg. So one needs at least about 5 doublings before batteries can reasonably compete which will start to occur if they have an energy density of around 32/ MJ/kg. Similar remarks apply to energy density measured by joules per volume. However, there are technical reasons to think that batteries will stop doubling before that (see theabove quora link for details which argues that we can't make batteries much than four times as efficient before we start running into serious theoretical limits). At around 20 MJ/kg, one maybe could run planes practically but they would be much less convenient and practical than today's jets and that would be at the very upper end of the plausible limits. So it is likely that we will still see fossil fuels used for jets for the next 40 or 50 years.