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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#341

Post by SOLAR_FIELDS »

modeless wrote: post #333
xkqd wrote: post #328

Earlier quoted context omitted.

You basically can run through a high capacity battery in less than 10 minutes, completing a light cleanup of a standard 1/4ac lawn. The battery itself will take 3-4 hours. Running through an entire block would deplete numerous batteries, meaning you’ve got to purchase 2 dozen if your crew is going to do the average 20ish homes a day. The purchase cost is one thing sure, but batteries are a consumable and the logistic…

I understand that they are less convenient and probably significantly more expensive for commercial use. That's why legislation is necessary, so landscapers who choose them aren't at a cost disadvantage. Externalities like air pollution are the textbook reason for regulations like this.

I mean we are talking an order of magnitude more effort and cost in exchange for noise pollution. I suspice if you told voters lawn care would quadruple in price in exchange for less (note, not eliminated) noise and air pollution that voters would not be terribly keen to approve such a solution.

Re: Students invent quieter leaf blower

#342

Post by modeless »

kjkjadksj wrote: post #336
SOLAR_FIELDS wrote: post #308

Earlier quoted context omitted.

And the other underlying problem implied there is that electric leaf blowers are only viable for household use. They are just so completely impractical for commercial use that no one will ever use them.

They are also nearly as loud to my ear as a gas one. Turns out blowing air is noisy.

Maybe they sound loud when you're using them but the difference is night and day when you're a bit farther away. I haven't heard a single electric blower that's louder than the quietest gas blower. And honestly the air pollution is my bigger complaint.

Re: Students invent quieter leaf blower

#343

Post by modeless »

SOLAR_FIELDS wrote: post #341
modeless wrote: post #333

Earlier quoted context omitted.

I understand that they are less convenient and probably significantly more expensive for commercial use. That's why legislation is necessary, so landscapers who choose them aren't at a cost disadvantage. Externalities like air pollution are the textbook reason for regulations like this.

I mean we are talking an order of magnitude more effort and cost in exchange for noise pollution. I suspice if you told voters lawn care would quadruple in price in exchange for less (note, not eliminated) noise and air pollution that voters would not be terribly keen to approve such a solution.

> lawn care would quadruple in price

Come on, they're expensive but not that expensive.

Re: Students invent quieter leaf blower

#344

Post by sidewndr46 »

KineticLensman wrote: post #294
sidewndr46 wrote: post #100

Earlier quoted context omitted.

It isn't so much the noise that bothers me, what I've never understood about leaf blowers is what are they meant to accomplish? When I watch people use them they either blow the leaves into the street or the neighbors yard. What do they think that does? Now on the other hand, I do own a very noisy leaf vacuum. But when I've collected a bag full I can just deposit the leaves in my collection container. They are taken…

I own a Stihl leaf blower and primarily use it to clear debris from the gravel paths in my garden. Because raking gravel also collects the stones. Debris includes leaves, leaf husks, beech nuts, catkins, and a range of other things that drop off trees. I use a big rake to clear the lawn (I actually enjoy the physicality of this task). All of this stuff is composted over the year in a large pile in a secluded corner o…

Now that you say that, it makes much more sense. It isn't like I go into my neighbors backyards and monitor them using their leafblower. So all I really see is the yard maintenance guy in the front yard. I'll commonly just see them blowing them into the street. Not all of them do this however.

Re: Students invent quieter leaf blower

#345

Post by [deleted] »

alamortsubite wrote: post #88
delichon wrote: post #52

Earlier quoted context omitted.

I lived in cities for four decades and rural areas for two. Hearing late night gunshots was routine in cities. I think it's happened once in hearing from my rural home. My neighbor is a state biologist who put down a sick coyote. Or course it can happen a lot if you get the wrong neighbors. But that's more of a risk in the city where you have so many more neighbors.

Wow, which cities? I've lived between cities and the sticks in the U.S. almost my entire life and while I've never once heard gunfire in a city, in the country it's a daily routine (occasionally, if rarely, even fully automatic).

[deleted]

Re: Students invent quieter leaf blower

#346

Post by WaltPurvis »

SV_BubbleTime wrote: post #233
tomoyoirl wrote: post #142

Earlier quoted context omitted.

Decibels are logarithmic; a 1 dB reduction in sound is ~26%.

But that is NOT the same as human perceived volume. Less 37% energy is not 37% less volume to humans. You won’t be able to tell the difference in volume except for the tone which could be more or less pleasing depending on the frequency they say they got 12db on.

I learned something new today (I didn't know decibels were logarithmic), but I still don't understand how it relates to "human perceived volume" as you put it. If a typical electric leaf blower makes 70 decibels of sound, it seems odd that cutting that to 67 decibels makes it sound 37% less loud. Perhaps it does, but I think I'll have to hear it to believe it. I may have to buy a sound meter and run some experiments.

Re: Students invent quieter leaf blower

#347

Post by tracker1 »

modeless wrote: post #342
kjkjadksj wrote: post #336

Earlier quoted context omitted.

They are also nearly as loud to my ear as a gas one. Turns out blowing air is noisy.

Maybe they sound loud when you're using them but the difference is night and day when you're a bit farther away. I haven't heard a single electric blower that's louder than the quietest gas blower. And honestly the air pollution is my bigger complaint.

Banning air freight would be more effective in terms of reducing pollution.

Re: Students invent quieter leaf blower

#348

Post by barfbagginus »

SV_BubbleTime wrote: post #224
xxs wrote: post #24

Earlier quoted context omitted.

I reread it - it says 40% reduction, that's -7dB... I can believe that part. Edit: checked DCBL772X1 - it's listed 68 dBA - that's not necessarily loud, so if they managed -7dB, massive props to them.

Except it is not. They claim a 2db reduction overall. Then they say that is 37% the noise. But it is not. Human hearing isn’t linear with power. 2db is not the human perceived volume. The article isn’t light on details - it’s bullshit.

During the great American knowledge collapse, it's becoming more and more important to make American students look smarter for working, like, less harder.

Re: Students invent quieter leaf blower

#349

Post by modeless »

tracker1 wrote: post #347
modeless wrote: post #342

Earlier quoted context omitted.

Maybe they sound loud when you're using them but the difference is night and day when you're a bit farther away. I haven't heard a single electric blower that's louder than the quietest gas blower. And honestly the air pollution is my bigger complaint.

Banning air freight would be more effective in terms of reducing pollution.

I'm not talking about CO2 for global warming here, it's negligible. This is local air pollution, polluting the air I breathe in my house and on my street. The other big offender in this category is wood smoke from fireplaces, which I would also be in favor of banning, though I understand this would be extremely unpopular (I know, I love a good fire too).

People don't realize that wood smoke is every bit as harmful as cigarette smoke and much worse than modern car exhaust. Many (most?) days in winter around here fireplace smoke is by far the biggest contributor to general poor air quality, and then there are the days when my neighbor's chimney smoke blows directly into my yard where my children want to play, for hours...

Re: Students invent quieter leaf blower

#350

Post by y-c-o-m-b »

sidewndr46 wrote: post #100
mikeyouse wrote: post #61

Earlier quoted context omitted.

Many affluent areas have already banned gas leaf blowers and it’s incredible how quiet the battery powered replacements are. I was in Palm Springs recently and had nearly walked past a landscaper using one before if occurred to me just how quiet it was - didn’t even interrupt our conversation. I believe it was a Stihl backpack version (maybe https://www.stihlusa.com/products/blowers-and-shredder-vacs/... ) but yeah,…

It isn't so much the noise that bothers me, what I've never understood about leaf blowers is what are they meant to accomplish? When I watch people use them they either blow the leaves into the street or the neighbors yard. What do they think that does? Now on the other hand, I do own a very noisy leaf vacuum. But when I've collected a bag full I can just deposit the leaves in my collection container. They are taken…

I use it to remove pollen, pine needles, gravel, debris from clippings, etc from my deck and drive-way. Sometimes I use it to clear out the gutters on my roof. I usually blow it all down into one corner then use a dust-pan and broom to collect it all and throw it in the debris bin. I hate it when people just blow the debris somewhere else; they're making it somebody else's problem and that's wrong.
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