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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#401

Post by alach11 »

xkqd wrote: post #328
kbenson wrote: post #324

Earlier quoted context omitted.

Why? I'm sure they're less practical than the gas powered ones, but every tool system with their own battery standard seems to have one. Even if you had to have a few batteries charged in reserve, that seems more like slightly more expensive and annoying than utterly impractical. Am I missing something?

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'm on the (admittedly expensive) EGO system of lawn tools, and I can mow, trim, and blow my entire yard (front and back) in a relatively normal lot (8000 sq ft) on one 10.0Ah battery. It recharges in 2 hours. So I think electric is a touch more practical than your numbers might represent.

But for commercial use I agree, the upfront capex cost is prohibitive. And the need for charging infrastructure (in truck or other) presents an issue.

Re: Students invent quieter leaf blower

#402

Post by kbenson »

slimsag wrote: post #330
kbenson wrote: post #324

Earlier quoted context omitted.

Why? I'm sure they're less practical than the gas powered ones, but every tool system with their own battery standard seems to have one. Even if you had to have a few batteries charged in reserve, that seems more like slightly more expensive and annoying than utterly impractical. Am I missing something?

They're not even in the same ballpark My 80v electric blower with a heavy battery runs for 21 minutes. A gas blower with 1.5 gallons of fuel will last 10 hours. A ban on gas blowers - or blowing in general - will only harm minorities already underpaid, often under the table.

> My 80v electric blower with a heavy battery runs for 21 minutes. A gas blower with 1.5 gallons of fuel will last 10 hours.

I found backbpack models (and if we're comparing professional services that's what seems we should compare) that claim 60 minuntes on high at 800cfm+ and 20 hours on low, with dual charger systems you can buy to supplement.

I saw numbers quoting that most professional leaf blowers go through about 0.43 gallons of fuel an hour. The top backpack blowers I looked up didn't even have a 1.5 gallon tank. The Echo PB-9010T has a 83.8 fl. oz. tank. The Stihl BR 800 C-E Magnum has a 67.6 oz. tank. The SCHRÖDER SR-9900X 80cc has a tank size of 75 oz.

If you have to stop to refuel every hour or so anyway, swapping out a battery that's been charging doesn't seem like a big inconvenience.

> A ban on gas blowers - or blowing in general - will only harm minorities already underpaid, often under the table.

I'm not sure we should be avoiding legislation meant to protect the public in general (air and noise pollution) because of possible affects to some specific subcategory (leaf blowing) of an industry (landscaping) which happens to employ minorities in a higher percentage than other industries. If we were to always do that, then we'd rarely ever have any useful public protections, would we?

How many professional leaf blowers per capita do you think we have, anyway, and if it costs more for everyone since it's regulated, why would the impact really be that great, since it should just mean they charge more?

Re: Students invent quieter leaf blower

#403

Post by philbin »

travisb wrote: post #375
actionfromafar wrote: post #26

Earlier quoted context omitted.

It will get there I suspect, the tools and batteries can charge in the truck en route. Easier to just fuel up the truck once instead of filling up little gas tanks all the time.

Charging using the truck would require running the truck all day -- probably not an acceptable alternative. Consuming 2-10 Kw from a 200 Kw engine would be so inefficient that it'd be too expensive anyways. Instead you'd need to run a generator all day charging batteries. A fast charging, high capacity tool battery takes at least 60 minutes to charge. In high power applications (lawn mower, leaf blower, chainsaw, etc…

This is nuts!

Instead buy 120-volt and 240-volt leaf blowers. BTW 2-3 horsepower is plenty (probably too much) for one man.

We use water hoses w/o bitching too much. We could used corded leafblowers tomorrow. Or butch up, get rakes and get in shape: cleaner air, more exercise and longer hours for the lawn laborers.

Re: Students invent quieter leaf blower

#404

Post by philbin »

ModernMech wrote: post #156
lowercased wrote: post #15

Won't help much until these are mandated by law, or.. we just wait for a couple generations to die out. There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. Over time, the next couple generations may hopefully adopt more battery powered outdoor stuff (mowers, blowers, etc) beca…

These were my neighbors growing up. Chain saws, quads, backhoes, bulldozers, fire engines, school busses -- anything with wheels and big motors they would be running all day long. Every day during the summer I'd wake up at 8am to 3-4 quads being driven around outside my window by the neighbor kids, and that would go on all day long until sunset. That actually wasn't bad though compared to moving to San Francisco, whe…

Earplugs really do work! Pay the money to get good ones.

Re: Students invent quieter leaf blower

#405

Post by vouaobrasil »

sandworm101 wrote: post #261
ericd wrote: post #212

Earlier quoted context omitted.

I'm guessing that the person you're responding to isn't a huge fan of huge expanses of tightly mowed grass in the form of golf courses, either.

Or the fire risks associated with having piles of dry leaves near to houses and such.

Obviously move them a little with a rake, but there's no need to blow them to make a 100% clean lawn. And of course, I hate golf courses.

Re: Students invent quieter leaf blower

#406

Post by atonse »

alach11 wrote: post #401
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'm on the (admittedly expensive) EGO system of lawn tools, and I can mow, trim, and blow my entire yard (front and back) in a relatively normal lot (8000 sq ft) on one 10.0Ah battery. It recharges in 2 hours. So I think electric is a touch more practical than your numbers might represent. But for commercial use I agree, the upfront capex cost is prohibitive. And the need for charging infrastructure (in truck or othe…

There are companies that make battery packs the sizes of small ice coolers that can serve as a charging “hub” on your truck.

Plus there are trucks like the f150 lighting that have electrical outlets so you could recharge in the field.

Thirdly, with 1-2 spare batteries that you can swap and charge, you basically have zero downtime.

Re: Students invent quieter leaf blower

#407

Post by travisb »

actionfromafar wrote: post #389
travisb wrote: post #375

Earlier quoted context omitted.

Charging using the truck would require running the truck all day -- probably not an acceptable alternative. Consuming 2-10 Kw from a 200 Kw engine would be so inefficient that it'd be too expensive anyways. Instead you'd need to run a generator all day charging batteries. A fast charging, high capacity tool battery takes at least 60 minutes to charge. In high power applications (lawn mower, leaf blower, chainsaw, etc…

Hybrid truck?

If you had a serial plug-in hybrid with a 20+Kwh battery which also supported exporting 120vac, that would work. AFAIK such a vehicle doesn't exist in North America yet and might not exist anywhere globally.

You start stacking energy efficiency losses (engine -> charger -> battery -> inverter -> charger -> battery -> motor) and economic losses (expensive serial hybrid, higher than expected vehicle battery cycles, still need a large number of tool batteries which wear out in about a year, etc.) though.

Re: Students invent quieter leaf blower

#408

Post by mlrtime »

kreyenborgi wrote: post #108
mlrtime wrote: post #75

Earlier quoted context omitted.

I use it to dry my car which is ceramic coated, one of the best tools I have recently purchased.

why would you dry a car instead of buy one that is water proof i would be leaf blowing my car every other day with the amount of rain here

I'm sorry, is this is sarcasm?

When you wash the car you want all the water off of it. Water isn't clean.

Re: Students invent quieter leaf blower

#409

Post by mlrtime »

mlrtime wrote: post #75
huhtenberg wrote: post #5

Earlier quoted context omitted.

Yep, it's invaluable for getting your BBQ grill really going.

I use it to dry my car which is ceramic coated, one of the best tools I have recently purchased.

edit: Sorry I meant when I wash the car. For some reason I thought that was obvious.

Re: Students invent quieter leaf blower

#410

Post by jauntywundrkind »

kjkjadksj wrote: post #300
modeless wrote: post #296

We don't need quieter electric leaf blowers. We need to ban the gas ones, with no grandfather clause. Not just for the noise pollution but the local air pollution. It's crazy the volume of air that can be ruined by a single gas leaf blower, far worse than modern cars, and they are inescapable in cities.

They’ve been banned for years in some cities. The issue is there is zero enforcement.

DC seems to be doing pretty great with our ban. Theres some loud-ish electrics but it's still 1/8th the horror that it used to be; it used to be that someone two blocks away was still creating a living hell, but now it's really just someone across the street with a particularly poor model.

Next up on my list, construction sites! We've had a small condo going up nearby, wood framed, and the generator is loud as fuck all the time. They use so little power though. A hybrid setup with 1kwh battery would let that thing rest 95% of the time. Ditto for their air compressor; a even modest sized 300 PSI air receiver tank would radically improve the neighborhood for nearly no cost.

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