A Garbage Truck That Would Make Elon Musk Proud 174
curtwoodward writes: Ian Wright knows how to build high-performance electric cars: he was a co-founder at Tesla Motors and built the X1, a street-legal all-electric car that can go from zero to 60 in 2.9 seconds. But he only cares about trucks now — in fact, boring old garbage trucks and delivery trucks are his favorite. Why? To disrupt the auto industry with electrification, EV makers should target the biggest gas (and diesel) guzzlers. His new powertrain is very high tech, combining advanced electric motors with an onboard turbine that acts as a generator when batteries run low.
General Moters (Score:4, Interesting)
There where plenty of electric vehicles prior to General Moters buying all the street-car companies and replacing the cars with diesel buses [slashdot.org].
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It's NIH (not invented here, not the national institute of health) and protectionism at its worst. Rail is invented in Europe and the technology is dominated by European companies. Obviously, we should double down on cars.
Taking this attitude to the extreme yields Detroit. Not suburban Detroit, but inner city Detroit. On the complete opposite side of the spectrum is New York City. I know where I'd rather live in and around.
Of course, it takes a country much, much longer to go bankrupt, but even at that leve
Moters? (Score:2)
Who is General Moters? :P
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Which both happen to be types of motors.
Hence, General Motors.
Some of this is happening at PACCAR (Score:4, Interesting)
They make trucks, they're near Seattle, and there are some UW engineering projects in doing stuff like that there.
They already have a number of hybrid trucks, and I know that fuel cell powerplants scale well in truck form.
Distance and Charge Time (Score:2, Informative)
The two major factors for electric usefulness are the distance you can go on a charge, and the time it takes to recharge.
You could cut out the middleman on this vehicle's charging turbine by removing the electrical system altogether and running it on gas, or diesel or propane.
I'm a Leaf owner (and soon to be a Fusion Energi owner), but the duration driving necessary by a fleet of garbage trucks isn't there unless you have a bunch of "tender" vehicles running them fresh batteries all day long.
Aside: I believ
Re:Distance and Charge Time (Score:4, Insightful)
but the duration driving necessary by a fleet of garbage trucks isn't there unless you have a bunch of "tender" vehicles running them fresh batteries all day long.
Except garbage trucks don't actually drive that many miles. Time, yes, miles, no. That makes them perfect candidates for electric. As far as the "tender" vehicles, it mentions having an onboard turbine so this is essentially a plug-in hybrid, where the key is efficiency.
Re:Distance and Charge Time (Score:4, Informative)
Its just like a British milk float. It spends a lot of its time stopped, so an engine which doesn't need to idle is more efficient.
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That is exactly where electric motors shine. When a vehicle is stopped, an electric motor requires zero energy to function except for cab climate control and computer devices. If one drives a hybrid or EV, stop and go traffic sucks a lot less with one of those than a gas or diesel engine which is chugging away at idle burning fuel. (Yes, one can start/stop the engine, but that may be more trouble than its worth, especially if it is very hot or cold outside.)
It only will get better. Once we get battery t
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Though when a garbage truck is stopped, it's usually lifting garbage bins, with big hydraulics... which need power too. So the engine isn't entirely 'waste' when it's not moving.
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Around here, the residential trucks have hydraulic arms that grab and lift a wheeled bin into the.. hopper thing.
Probably a lot less power required than for the compacting rams, but power nonetheless.
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Regenerative brakes are never net plus. Simply driving better is more efficient, if traffic lets you.
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never is a bit too strong of word. yes regenerative breaking is often thrown in as a feature and talked up in applications where it has little to no benefit but that doesn't mean there aren't circumstances where it's beneficial
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As the other poster size garbage trucks drive a lot but so far. . They get their high milage over time. A garbage truck wouldn't have to run all day long. In fact it idles most of the day. An electric vehicle doesn't have to idle. A leaf is perfect for round trips to an office job.
Re:Distance and Charge Time (Score:5, Informative)
An electric drive train weighs a fraction of what an axle drive train does for those monsters, and an electric motor is MUCH better for a stop&go traffic pattern due to resting torque differences and regenerative braking.
Plus the generator can be tuned for a singular operating RPM since the battery bank will be buffering the energy. That right there simplifies the engine and boosts efficiency.
I'm a fan of the electric + generator hybrid setup. It can take advantage of the existing fuel infrastructure for distance, while giving efficiency gains and allowing designers to use a wider range of engine designs for the generator. I would guess there are a couple engine designs out there that are more efficient/powerful for the mass and/or volume but can't do the variable RPM a 4-12 piston IC does.
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I can't wait for to be woken at 5 AM when the turbine generator fires up outside my bedroom window ;(
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I can't wait for to be woken at 5 AM when the turbine generator fires up outside my bedroom window ;(
The garbage trucks active at wee hours are usually emptying dumpsters. The engine noise is least of your worries compared to the sound of them slamming a half ton steel box up over the truck then down onto the pavement.
As a former weekly 3:00am victim of this practice at an apartment I used to rent, I think that operating any garbage truck between 11:00pm and 6:00am should be made into a felony.
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In my personal experience, hybrid garbage trucks are significantly less noisy than normal ones.
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Yes I would agree. Its just that I used to hang around the test stand in the engine factory for the Australian fleet of FA/18 jets and those things are very loud.
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They are also huge, with the according airflow. Piston aircraft with comparable performance was actually way louder.
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I think most of the noise is from other sources anyway... like this [youtube.com]
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Regenerative braking doesn't do a whole lot when the vast majority of your stop & go driving never gets above 10 mph with only 100 feet or so between stops.
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According to the article the conversion kit costs $100k and it has no mention to lifespan.
But say your lifespan number is correct, lets look at this.
8 hrs a day, 5 days a week, 52 weeks a year for a fulltime 100% driving duty vehicle = 2080 hours/year.
So already this conversion would last 5 years at a bare minimum. Please note the article suggests a 3 year payback time on this, meaning a possibility of an extra $66k of savings for the medium duty kit.
Of course that would require the turbine to be running fu
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Please note the article suggests a 3 year payback time on this, meaning a possibility of an extra $66k of savings for the medium duty kit.
A 3 year payback time is really quite good, in the region where garbage truck operators will do it without any additional incentives.
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Which one of those supports regenerative braking? I would think regenerative braking would be the single biggest win on a garbage truck. And you only need a small battery to do it on a hybrid.
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Aside: I believe all curbside trash pickup is a conspiracy to generate HOA fines.
I have a fix for that - don't live in an HOA zone. HOA's *suck*, and the only thing keeping them around are people willing to live under their rule.
Low hanging fruit (Score:5, Insightful)
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FIRE TRUCKS: They rarely have to travel more than a few miles at a time, with plenty of time to recharge. And they're all ridiculously expensive already, so the added cost of batteries is insignificant.
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What starts with "F" and ends with "U-C-K"? Fire truck.
Engines are more than just for movement: (Score:5, Insightful)
Fire trucks have to use their engines for extended periods to run the on board pumps during major fires.
Bad enough having to find a hydrant. Imagine having to find an electrical outlet with sufficient current capacity to keep electric pumps going after the batteries are down.
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Sure. Or, just make it a hybrid drive with charging from the grid and have the best of both worlds.
Fire trucks are a small enough part of the vehicles out there to be less of a worry for efficiency. Reliability is a big thing for emergency vehicles.
There are a lot of garbage trucks and other utility type trucks out there that do short range stop and start runs that would probably make a lot bigger difference.
Re:Low hanging fruitfor (Score:2)
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IIRC there was a product advertised some years ago. Its basically a contractors truck with an integrated generator. The focus is on supplying power to a construction site, and traction runs off the same power source.
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Sort of. Quick Googling suggests that 1:3 miles school buses drive are to events - taking kids on field trips, taking football teams cross-town to games, etc.
You'd need one set of buses to do the morning pickups and afternoon drop-offs, and another set of buses to take kids cross-town on a Friday night for a football game or to the next town over for the band regional.
OTOH, charging the Google Buses that don't pay the drivers mid-day (split shifts: LOL) would be dandy.
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Or convert a portion of the buses and optionally, make the long haul buses plug in hybrids rather than just electric.
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Yeah, you are right. ... and people _walking_ with luggage on their back on a highway out of the city. ... (* face palm *) Well, the "fleeing" people on foot whe
It is completely impossible to electrify a set of busses for ordinary school transports and keep some busses as diesels for long distance over land hauling.
Reminds me about the pictures of the Katrina Hurricane, a parking lot full with minimum 100 school busses, under water
It was completely _impossible_ to use those busses to evacuate the population
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Well, yeah, it was. A motor vehicle that's been submerged isn't going to run, at least not until it's been repaired.
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Yeah, and that mindset is the reason so many people died.
The busses would have been supposed to evacuate the city before they got submerged!
The busses had no place on the parking lot at the first place! Either national guard or fire fighters or the army themselves should have confiscated them and rescue people! If the 'city' has not the 'guts' to order the drivers or ask for volunteers!
And for your interest, no I did not forget the closing html tag ... seeing a city and its people drowning while everyone wh
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Schools are too poor to pay for a whole fleet of brand new buses and the charging infrastructure around it. And since the largest and majority of school systems are publicly funded, there's too much oil money floating around to allow this to happen anyway. It might work for private schools, but they're also operating on thin margins and there's oil money there too.
Not to mention it'd be a PR disaster waiting to happen. One school bus fire involving the batteries, and you'll bet there's big oil ready to scre
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Schools are too poor to pay for a whole fleet of brand new buses and the charging infrastructure around it.
If the batteries reduced the buses' operating costs to the point where the upgrades/purchases would pay for themselves in a few years (and that's a big if!), it would not be difficult to arrange financing for the buses. The schools wouldn't have to pay anything extra, and the schools and the lenders would split the savings, profiting both parties.
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SCHOOL BUSES. Usually low-speed, frequent starts & stops, usually only out for 2-3 hours at a time.
Inner city school buses, sure. I live in the country. Even out here, though, a hybrid system might make sense. Relatively little battery coupled with a KERS-style system to permit absorbing significant power while regeneratively braking, and a plug-in mode to permit clean operation while traveling through the residential sections or while actually at the school, and to perform acceleration operations in general so that the dirty diesel doesn't have to. Since they're automatics these days, you can hybridize
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Fun fact, last time hybrid buses came up because of Seattle's disappointing results with them, primarily due to new EPA requirements wrecking the efficiency of the diesel engines), I figured out that the standard bus has about the same horsepower as a Tesla Model S. The primary reason for using a diesel in school buses and such is for torque, reliability, and fuel economy.
So 1, maybe 2 Model S batteries would be able to provide all the current a school bus needs.
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I figured out that the standard bus has about the same horsepower as a Tesla Model S. The primary reason for using a diesel in school buses and such is for torque, reliability, and fuel economy.
The bus taking off from a stop all the time is like a Tesla making a 0-60 run from every light.
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Just changing to direct injection diesels with better gearboxes would be a large improvement, yet it doesn't happen. Schools are broke. The school buses around here are as old as me.
Wondering why it took so long... (Score:5, Interesting)
This conversion of diesel trucks to diesel-electric or gas-turbine-electric trucks is long over due. In the case of steam locomotives, the efficiency went from 6% for steam to 15% diesel-electric. But coal was much cheaper than diesel. Here the efficiency boost is probably from 20% to 30%. Going from expensive fuel to slightly cheaper fuel. It might not beat the speed at which steam was made obsolete. But it could come close.
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Currently there are hybrid diesel/electrical double decker buses on trial in Hong Kong [www.kmb.hk]. Lots of stop and go traffic of course, which is what the trial routes have been selected for as there the most savings can be made. No more idling engines for starters!
How these would work for long-distance travel like trucks tend to do, I don't know. Savings will be far less there.
Re: Wondering why it took so long... (Score:2)
We've had hybrid double deckers in. London for at least three years, including the new Boris Buses
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The ability to accurately control an electric motor is probably a big reason why this took so long. Electric trains from that era have really crude systems for selecting a speed: the motor had several windings which you could switch on or off, or place them in series or parallel. Then there were resistor banks for intermediate settings. So instead of a smooth "analogue" throttle, you had maybe 10 speed/power settings to choose from. This sort of works for a train: there's enough inertia that you can switch
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In the case of steam locomotives, the efficiency went from 6% for steam to 15% diesel-electric.
You'd have had even better efficiency with direct diesel... if a drivetrain could be developed that would handle it. That's the only reason why diesel locomotives use an electric powertrain. You can't meaningfully store all that power in the locomotive, especially since braking is spread out across the train. The only way to meaningfully make long-haul trains hybrid is to power each car like a subway train. We could retrofit existing cars by replacing the bogeys, but it's a fairly massive undertaking. Havin
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Why would you switch trucks to a less efficient system? Would you really put a 200kW+ electric motor in just to get rid of first gear?
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Well, apart from sunk cost, and upgrade cost. Which is why East Germany ran some steam trains almost until reunification! (though I'd imagine they'd have been converted to oil firing by then, which brings down the work load a bit).
Coincidentally, pretty much the only place that can repair or build full size locomotive steam boilers today is in Germany. It's something of a lost art, I guess. When the UK commissioned a new steam train a few years back, they had to get the boiler made in Germany. No one left i
At last a good idea (Score:3)
I believe electrics and hybrids are overrated most of the time : huge costs and environmentally friendly don't mix that well in my mind.
Garbage trucks are a nice low hanging fruit and are universally needed. Whatever place they're to be found before/after their work day so to speak is where you can do electrical charging and maintenance (and maybe the same for other municipal vehicles)
If electric somewhat hybrid garbage trucks make sense, they'd be welcome everywhere, even/especially in African and Asian countries.
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Seriously we need to make bicycle commuting a social norm in this country. You save gas. You save money. Instead you burn fat, which you normally pay to get rid of anyway (gym membership, diet counseling, etc)
That's not going to happen until we spend a ton of money and make safe bike lanes and roads, instead of expecting cyclists to share the road with idiot drivers in giant SUVs applying their makeup and texting while driving.
Worse, even if we did that, in many locales it still wouldn't be very popular bec
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Bike roads ought to be rather cheap : not much weight is applied on them by the vehicles.
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True, but you're still looking at miles and miles of them, and where exactly do you put them? To be safe, they need to be separate from car roads (just watch, some cycling extremists will jump down my throat here and say it's perfectly safe to ride inches away from 6000-pound SUVs driven by people texting), but in most places, there isn't enough space to do that since the buildings are already there, so you're looking at either turning the sidewalk into a bikeway or narrowing the road, both of which are ge
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Re: At last a good idea (Score:2)
Or, you can take road space away from autos and dedicate it to bikes. There's a lot of outrage when you do it, but it's possible. Google London super cycle highway debate to see how this is playing out in the UK.
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Or, you can take road space away from autos and dedicate it to bikes. There's a lot of outrage when you do it, but it's possible. Google London super cycle highway debate to see how this is playing out in the UK.
I don't see how you could possibly do that, because now you've made it impossible for cars to get to many homes and businesses, or worse delivery trucks. How do stores get stocked when there's no road for the trucks to bring the goods to the stores to stock them? How do people get from town to tow
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That still doesn't answer how car traffic is supposed to get around. You're talking about completely removing cars as an option for travel where I live. Voters will never approve that. This approach works in dense cities like Manhattan where walking is normal, there's no driveways (only street parking), and there's lots of streets in a grid, so it's no big deal to shut some of them (the smaller, non-thoroughfare ones) off for pedestrians and cyclists, and let car traffic go around. In a place where ALL
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I'll second the bike lanes, and I don't mean a 3 inch wider shoulder on the road. I have ridden a bike on the roads perfectly legally and it was damned scary. I'm not sure what's worse, the screeching tires behind me or the people whizzing by 10 MPH over the limit 4 inches from my left knee.
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Exactly what I'm talking about. All it takes is one slightly wrong move by an idiot driver and you're either in the hospital, maimed, or dead.
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That's not going to happen until we spend a ton of money and make safe bike lanes and roads, instead of expecting cyclists to share the road with idiot drivers in giant SUVs applying their makeup and texting while driving.
Moreover, it's not even a good idea without doing that. If you don't have a bike lane, you've just created zillions of choke points at which the cars will be decelerating and accelerating again. It's going to actually cost energy unless basically everyone does it. That kind of thing can't happen overnight, barring global cataclysm or alien invasion :p
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The others are more clunky and might confuse readers. With "Minnesnowta" it's easy to tell the state name. I don't think I would have picked up what "Flooda" is referring to, and I definitely would not have gotten "Phurnace". And Arizona being arid really isn't a problem; Southern California is arid too, but the weather there is great because it's mild and it's right next to the ocean (the problem with SoCal is the LAPD and all the crime, not the weather). Arizona (the southern part, where Phoenix is) i
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For a moment I was shocked about the temperature, until I realized it must be Fahrenheit :)
Regardless, cycling in either -40 Celsius or Fahrenheit is not a problem at all.
Question is: do you have deep snow, ice or strong cold winds; all that would be annoying.
But cycling under clear sky with sun and an inch or two snow on an otherwise not to icy road is a perfect day!
Like cross country skiing.
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For a moment I was shocked about the temperature, until I realized it must be Fahrenheit :)
Have you forgotten that -40F is exactly the same as -40C?
But cycling under clear sky with sun and an inch or two snow on an otherwise not to icy road is a perfect day!
If you're a seasoned and extremely fit cyclist who's used to such temperatures, sure. If you're some average person, fuck no.
The world's most bike-friendly city is usually cited as Copenhagen, Denmark. Go to Youtube and search for "copenhagen biking" o
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How the hell then do people there manage to get out of their home at all and not freeze to death?
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I imagine they wear heavy coats and layers of clothing, and don't stay outside for very long, just enough to get from their house to their car.
Walking around for a few minutes in a heavy parka is very different from riding around at 10-20mph on a bike for 30-60 minutes.
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There's considerable heating when you ride, from your metabolism and muscles etc.
It makes riding at -5C (23F) a piece of cake and I think the worst I ever experienced was -10C (14F). In fact the problem then is when entering a building, that's like a heatwave and you're heavily sweating. Have to stand outside a bit, waiting to cool off.
I would love to try riding at -30C to -20C (-40C? if the "warmer" rides work out and even then maybe not!). I have no experience of these temperatures whatsoever. I'd fear so
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You're forgetting the wind chill, and all the extra clothing you have to wear which makes it very difficult to have the proper range of motion necessary on a bicycle. Plus, how do you keep your head from getting too cold? Bike helmets are great for ventilation, but that's exactly what you don't want in very cold temperatures, and they don't cover your ears at all. Back in college when I rode in temperatures like you describe (down to the teens), I wore a thin skullcap under my bike helmet, but that's not
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There are thicker skullcaps and they also cover the ears. Might not fit the current helmet so you would need a second helmet for the winter.
To me, personally, given decent clothing and spiked tires, the worst thing about cycling in winter is having to be slow enough so I don't have to breathe with my mouth, and this takes a lot of fun from cycling.
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To me, personally, given decent clothing and spiked tires, the worst thing about cycling in winter is having to be slow enough so I don't have to breathe with my mouth, and this takes a lot of fun from cycling.
To me, personally, given a nose that doesn't work properly, I would just die. I have Asthma. I'm never, ever switching to bicycle commuting. Even with power assistance I would still arrive totally wrecked. There will always be people who cannot or will not bicycle, for reasons like these. Rather than trying to enable everyone to bicycle, we should look at alternatives that would solve existing problems and still permit people to go about their lives, e.g. PRT. It's going to be a much easier sell than cyclin
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The thing is, cycling is, in fact, good enough for most of people but you are suggesting to optimise for fringe cases like you first. It is way easier to optimise for the majority and to take care of special needs separately.
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Yep, I'm a big big fan of PRT like SkyTran. However every time I bring it up, naysayers just tell me how it's "impossible" even though it's just using existing technology and was probably technologically doable back in the 80s or 90s (meaning it's quite easy today with current computing and navigation technology), that "it'd cost too much" even though it's far cheaper than light rail or monorails, etc.
If we had had Slashdot back in the mid 1960s, people there would have gone on and on about how it's utterl
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If you have asthma, you should move to a place with fresh air and should start cycling. ... and cycling is very likely the best sport, except perhaps for martial arts, Karate or Aikido, or sailing/rowing.
A no brainer, any competent doctor would tell you so.
Doing no sports because you have asthma is only putting worse to the worse
If you are scared, consider three wheel bikes or bikes where you ride in a half lying position (and yes, an extra electro drive makes sense, too), then you can simply stop and keep
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No, I did not forget that -40F equals -40C, I never knew it at the first place. We use C in Europe, and I'm proud that I have a rough idea about temperatures in F above zero :)
Regarding temperatures: sorry, in a dry environment it is irrelevant how cold it is as soon as you start moving your body and you at least have some 'normal' clothing you heat up extremely.
So, yes skiing or biking in -40 degrees is no problem at all, after 5 minutes you have to start to undress your heavy cloth (in case you wear heavy
Missed opportunity (Score:5, Funny)
1950.s Milk Floats in the UK (Score:5, Interesting)
They were milk delivery trucks (called "Milk Floats") which typically delivered milk around town in glass bottles to people's doorsteps at around 5-6 am every day. That was before most people had fridges but wanted fresh milk every morning. They ran on batteries and had a top speed of about 8mph.
It was ideal, like it would also be ideal for rubbish (US garbage) collection. Electric drives are good for the constant start-stop driving with long-ish pauses in between. Also the early morning milk floats did not wake people up as a IC-engined truck would have done.
Fridges and car ownership brought an end to most doorstep milk deliveries, but there are still some around [milkfloats.org.uk].
Re: 1950.s Milk Floats in the UK (Score:2)
I remember milk coming this way in my childhood. It was great. We had a little milk bottle holder in which we would put the empties and set the indicator to say how many pints we wanted that morning. It was quiet, clean and environmentally friendly (the bottles were washed and reused many times before being recycled, in addition to the lack of pollution from the milk floats). But British retailing is a vicious business and tesco et al were just too fierce for up the dairy companies
Elon Musk had nothing to do with this (Score:5, Insightful)
The only purpose for putting Elon Musk's name in this is to grab the attention of the reader by dropping a popular name, I'm sure that he isn't proud of this truck; the article doesn't even mention his name. I'm sure that the "editor" that put this up didn't even realize they weren't talking about Elon Musk, they just skimmed through, saw "Tesla Co-Founder" and assumed said article was about Musk... I want to even say that the two aren't even on good terms anymore for some reason, something the "editors" should have looked into.. I'm with Steve Jobs on this one, Bloggers are not Journalists.
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Long distance freight: (Score:2)
The short haul is a lot easier to do with batteries.
I like the idea of catenary wires or some other way for a truck on a freeway to get electric power from the road itself.
Use battery or a hybrid system to get from the customer pick up to the nearest interstate and them hook up to the electric for the long drive, and let the truck drive itself. Have that lane separate from the manual driving lanes.
An alarm sounds when it's time for the driver to take back over (or stops the truck in a safe place if the driv
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They call these freight trains. In some countries, trucks are taken from town to town on flatbed rail cars.
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I'm quite familiar with intermodal transport. It becomes useful on longer runs. But, being able to just hook in to a powered feed is a lot more flexible.
For intermod, you have to have a truck and driver on either end of the rail link, plus the time to assemble the train, etc. It's quite efficient in a lot of ways, but unwieldy for mid range loads.
Good video on this (Score:4, Informative)
Capstone Turbine Corporation makes the LNG burning turbine for this application. Here [youtube.com] is a good video about it, showing the vehicle in operation and explaining the trade-offs; basically high initial capital costs with good long term savings in fuel and maintenance. Regenerative braking is a big win both in fuel savings and maintenance for garbage trucks which can perform more than 1000 hard stops per day.
Technical details on the turbine include; 200 lbs, 250 hp, 40,000h service life between overhauls (13+ years @ 8h / day.) The turbine has air bearings to eliminate wear, which implies a gas generator/power section arrangement to drive the generator, I believe.
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Technical details on the turbine include; 200 lbs, 250 hp, 40,000h service life between overhauls (13+ years @ 8h / day.) The turbine has air bearings to eliminate wear, which implies a gas generator/power section arrangement to drive the generator, I believe.
A gas turbine is composed of two sections- a compressor and a power turbine. Probably they are using some compressor bleed air for the bearings (which is expensive, effeciency-wise). It still doesn't make sense to me though. Diesels in that size are much more efficient, more tolerant of abuse, more tolerant of contaminated fuels, and a lot cheaper to maintain. The only reason to use a gas turbine is when weight REALLY matters. We're talking about a garbage truck here. 100-200 more pounds for a diesel
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Diesels in that size are much more efficient, more tolerant of abuse, more tolerant of contaminated fuels, and a lot cheaper to maintain.
Citation? In the video it mentions that a diesel replacement for the power of the turbine would be 2000 pounds, not 200. Not exactly the same size. He also specifies that the turbine requires less maintenance. The turbine(which shouldn't be running all day) is rated at 40k hours(4.5 years continual operation), doesn't use oil lubrication or have a cooling system to worry about. Service parts are filters - fuel and air.
Looking up diesel garbage truck information [lelubricants.com] - I found a study where they had a servic
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In the video it mentions that a diesel replacement for the power of the turbine would be 2000 pounds, not 200
Well, if he really said that, he's a dirty liar. You can trivially get 250HP from a 7.3 powerstroke, which weighs about 1100lb wet.
Looking up diesel garbage truck information - I found a study where they had a service interval of 225 hours, probably about every 3-4 weeks. The study mentions going with special motor oil containing stuff that enabled them to 'extend oil change intervals by six times'. So I think that figuring on an oil change between 1-3 months is reasonable. That adds up.
Sigh. No. You are applying statistics without understanding. The most common system to fail on a garbage truck isn't going to be the engine. The engine isnot receiving service every 3-4 weeks. A truck that unreliable would be sold for scrap. The most common point of failure is the hydraulic system. Diesel engines regularly run for literally hundreds of thousands of miles without
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Except that regenerative braking doesn't work well at low speeds.
But you can get higher speeds by increasing the size of the motor, which increases the speed at which the armature passes by the coils, or the magnets, or whatever your design has that ain't moving. And there's room for that on a trash truck.
Re: (Score:2)
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Bigger motors aren't going to help the fact that there's just not that much kinetic energy to recover at low speeds
A typical garbage truck weighs upwards of 40,000 pounds empty. A typical full-size car is around 4,000. Tell me again how there's not much kinetic energy at low speeds. If you couldn't do regen until 15 then they were geared wrong.
Re: Funny (Score:2)
I think he meant "a non-negligible" number. Aldi and Lidl hold only a few percent of the British retail market, but it's still significant, in that the big four supermarkets are all seeing margins erode, sales drop, and share prices fall. Same may be true here, in due course.