Solomon Technologies - "Electric Wheel" electric motor propulsion systems

Discussion in 'Hybrid' started by lockhughes, Jun 18, 2002.

  1. lockhughes
    Joined: Jun 2002
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    lockhughes ElectricGuy

    I was stunned when I first read about what these guys are doing:

    http://www.solomontechnologies.com/

    It's pretty much an academic exercise now, but I was trying to sell my club membership on the merits of going with an electric pontoon boat rather than a displacement hull diesel-powered craft, as a replacement for our Club's tender, which operates as a 40-passenger private ferry on a 1 mile run between our Club and the city, across Toronto harbour.

    I've put together the scraps of my investigations so far, as a Yahoo Group site, at:

    http://groups.yahoo.com/group/QCYCTender/

    But about these Solomons? Anyone here with experience with these drives? Anyone think they're not bloody *amazing*???

    Regards

    Laughlin Hughes
    Tornado Kc234 "High Heels"
    QCYC
    Wards Island, Toronto
     
    1 person likes this.
  2. trouty

    trouty Guest

    interesting, but already outdated technology really.

    When you look at my plasmoidal induction scalar electromagnetic propulsion system (pat pend) you'll see that it's performance peramaters far exceed those of the electric wheel depicted above.

    Of course the reduction in input energy costs also make plasmoidal induction propulsion the system of the 21st century!

    The phase locked conjugate pair waveform scalar electrical energy of the plasmoidal induction engine is the secret to this system. That and the latent energy trapped within time are the keys... E= Delta TC squared, s what it's all about Tesla really is the one who discovered it.

    This is basically what makes it tick!

    [​IMG]

    Now - I'f I could just find a barge the size of the Queen Mary to carry the damn batterys! ;o)

    Cheers!
     
  3. Polarity
    Joined: Dec 2001
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    Location: UK

    Polarity Senior Member

    Laughlin

    Thats a very interesting site, I wrote to them about a 85hp replacement for my new boat. - I will let you know - it does look as though it might be prohibitively expensive though, compared with dropping in a recon diesel.

    If it could be "designed in" with the batteries and genset as part of the permanent ballast that would be a major benefit. For where I am going ( see www.polarity2.com ) I would need to look at heating the battery compartment due to the performance drop.

    Always looking for something new!

    Cheers

    Paul
     
  4. lockhughes
    Joined: Jun 2002
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    lockhughes ElectricGuy

    Re: interesting, but already outdated technology really.

    Wow. Trouty, I have no idea what you are talking about! Sorry! I really know zip about all this stuff. Trying to learn, but you're way, way over my head. Could you translate? Were you kidding?

    Lock
     
  5. lockhughes
    Joined: Jun 2002
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    lockhughes ElectricGuy

    Hi Paul. Expensive, maybe, if you're looking *only* at purchase/install costs? I checked out your Polarity2 site (v.nice!), and I'm guessing (deisel) refueling might be a bit more problematic than regenerating while under sail? High lats. might drop solar output, but wind generators?

    yeah. brrrrrrr! :) That's interesting though (cold temp. performance drop). Something that the eboat message threads I've seen haven't touched on.

    Lock

    ps... I knew those two, that did the NWP in the Hobie... specially made carbon-fibre version... Took `em out for a sail when they first got a Hobie to learn about cat sailing.
     
  6. Portager
    Joined: May 2002
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    Location: Southern California

    Portager Senior Member

    Solomon Technologies

    I reviewed the Solomon Technologies web site and their approach seams sound to me. I noted that they are using DC generators and AGM (Absorbent Glass Mat) batteries. This is technically sound and for the right application it is certainly feasible.

    One thing to keep in mind in considering the operating cost is the batteries are consumables. Depending on your level of discharge you will get between 400 and 1,000 charge/discharge cycles out of them. Then it will be another $1,800 dollars to replace them. By the way, does Solomon Technologies agree to provide replacement batteries at this price? This is a highly discounted price for Lifeline AGM batteries (probably close to their cost) so I would make see if they will provide your next set at a comparable price.

    The cost trade-off looks much better is you can eliminate the generator and use regenerative power or shore power to recharge the batteries. My main complaint would be the battery charger. At 8 amps and using a charge acceptance of 0.95 it is only restoring 7.6 Amp hours per hour. If the batteries are 50% discharged and you only bulk charge it will 4.15 hours to recharge. It would be nice to have a faster charger.

    It appears that when they talk about achieving hull speed they mean the square root of the length and not 1.xx time that. Portager (my dream boat) will achieve 1.15 times the square root of the water line length (6.8 knots) with 15 HP but the displacement speed actually goes up to 1.6 times the square root of the water line length or 9.8 knots which requires 68 HP. I plan to use an 80 HP engine which will give me about 10 knots maximum cruising speed. If I went to Solomon Technologies diesel-electric hybrid propulsion I would be limited to 5.8 knots. Those extra 4 knots take a lot more horse power but sometimes the 69% faster speed would be nice to have. For example it would be the difference of 17 hr versus 10.2 hr on a 100 NMi passage.

    The feasibility of the system is very application dependent. It works well on displacement sailboats that can tolerate the weight of the batteries and intend to sail most of the time. It also works well on a boat that only makes short trips like your pontoon boat. It doesn't work as well on lightweight multi-hull sailboats because of the weight of the batteries. It also does not work for long range power boats. The worst application is any type of planning boat.

    Cheers;
    Mike Schooley
     
  7. ewhel
    Joined: Jun 2002
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    ewhel Junior Member

    Solomon Technologies

    HI Folks....David Tether here. Have been forwarded a bunch of email stuff that suggested you all had questions....so I checked in and logged on! Having read the emails with interest I will submit one basic premise....We have studied this something fierce for 6 years. Several basic things about fossil fuel motors...they are here to stay for awhile because it is hard to achieve the power densities with any other medium(and the big three/Oil companies won't let you any way), Fossil fuel motors are over rated(motor torque rating at some RPM where you can't use it constantly, Parasitic losses are on brand new pumps, impellers, alternators (with charged batteries) and with new belts, they are oversized to be able to push a prop at start-up rpm's, and anyone that thinks the average boat transmissions are 98% efficient needs a new drug. Also...through there support systems have to be entirely variable and have Idle capability
    Having said this....the average generator, because it is ballanced and blueprinted to make electricity with a ballanced load can convert fossil fuel into electricity at about 45 to 70% efficiency. Now the battery pack becomes your second fuel tank and allows the generator to only run at it's optimum efficiency. The battery pack is your source for quick, on demand high demand, current draws. What happens is that whenever you use fossil fuel it is always converted at the highest efficiency. This also allows one to adjust the batteries and generator to the mission profile....large batteries with small gen...small batteries with large gen...small batteries with small gen....large batteries with large gen.
    Didn't want to ramble on just a beginning primer....
     
  8. Portager
    Joined: May 2002
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    Portager Senior Member

    Re: Solomon Technologies

    I won't decent to the level of exchanging petty insults. I will, however provide the following information to support my statement.

    COTTA TRANSMISSION COMPANY LLC BELOIT WISCONSIN 2001 http://www.cotta.com/tech3.htm "Cotta's rule of thumb for losses is 2% of the rated input HP per loaded gear mesh - "worst case"."

    For a marine transmission with one "loaded" gear mesh 98% is reasonable.

    Freeware Propeller Calculator <http://www.yosc.ukgateway.net/propcalc.xls> they assume a 3% power reduction for each gear box and a 1.5% power reduction for each bearing.

    I won't squabble over 1% you can call it 97% if you like.:)

    Nautica Magazine / Propellers <http://www.nautica.it/info/motore/eliche_e.htm> " SHP (Shaft Horse Power) is the power actually delivered from the engine to the shaft thus to the propeller, about equal to the BHP (Brake Horse Power, meaning the maximum engine horse power as tested at the factory) minus about 3% of power loss at the gearbox and 1.5% per bearing."

    Seams to support the 97% rule of thumb. I would like to point out however that with helical cut gears you can do considerable better and reduce the noise level at the same time. These gear boxes are normally used only on high power applications where cost isn't the main driver but heat build-up is a problem.

    ::: Howard Arneson Tribute ::: <http://www.howardarneson.com/articles/article7r.asp> "Remarkably, there is virtually no power loss from engine to prop [with the Arneson Drive]. Most stern drives create a 15 to 17 per cent loss of efficiency because of their complicated gear composition. The Arneson Drive, however, avoids this and only about one percent loss is created by minimal bearing friction."

    I suspect that the Arneson Drive that the article is referring was using higher cost gearboxes, but the main reason I provided this reference is to shed some possible light on the disagreement. If David is using a Sail drive or thinking of the efficiency of a stern drive that could explain the discrepancy. Just a thought.

    Cheers;
    Mike Schooley
     
  9. trouty

    trouty Guest

    Joking? - moir? smatter of fact - no - I wuz deadly serious!

    It'd be nice to think I was joking and all this scalar electromagnetics stuff would just dissapear, but the truth of the matter is, it actually works!:eek:

    Thats why the US patents office granted a patent a few weeks ago.

    http://www.prahlad.org/pub/bearden/patent_meg.htm

    Yep - the electronic wheel is great - BUT imagine how good it will be when - you don't need to keep charging and discharging batterys to power it but you harness the free energy trapped within time, ony using the battery source once to initiate the system!

    Free energy - are you with me here?...

    No diesel fuel - no hydrogen cell no nuthin - just a MEG (Motionless Electromagnetic Generator).

    Course - you can couple MEGs inline for additional power, and if you want to you can run them thru the electrioc wheel to power a propellor - but how agricultural is that? :rolleyes:

    Bout the only thing missing is the guy standing at the prow beating the drum! ;)

    Noo - once people cotton onto scalar electromagnetics - the world as we know it today in terms of energy needs will be totally changed as if in the blink of an eye - forever more.

    Think back to pre 1943, and Hiroshima/ Nagasaki...

    Who'd a ever thought there was enough energy trapped within the atom to do that much damage to whole citys full of people?

    Who'd have ever thought that we'd have whole US naval Carrier battle groups & submarines at sea, powered by - nuclear reactors - harvesting the energy trapped within the atom?

    What "momentous discovery" led us to nuclear energy?...

    Well - Albert Einstein had a bit to do with it...when he formulated his "general theory of relativity" (never loan munney to relatives) :D...er no - sorry, I mean E = MC2

    Sooo....Now I come along telling you that Tesla's discovery of scalar electromagnetics, has given us E=TC2 where T is delta T or change in time, and suddenly - I'm telling a big joke???:confused: :confused:

    Why is it so "unbelievable" that there could be as much energy trapped within time as there is withing the atom?:confused: :rolleyes:

    You see, it's something like the atom before 1942....the energy was always there - we just werent smart enough until then to realise a way to harness that energy trapped within the atom.

    In the same way - there is the same amount of energy trapped within time...IF we just understand the physics that allows us to harness that energy. The MEG or motionless Electromagnetic Generator as described in the patent and depicted here:-

    [​IMG]

    is REALITY people - it's real - it works - the energy is free!

    Just think for a few seconds...what that means in terms of "boat design" never mind about the implications for our western oil based economies and all the wars we are about to fight in the middle east and caspian basin over oil.....just think what "unlimited free energy" means to the world!

    Hows it work?...

    Well, if you have the time - you could start reading here and sooner or later the penny will drop!

    http://www.cheniere.org/techpapers/Final Secret 9 Feb 1993/index.html

    Now - the guy who has compiled all this is a former US Colonel (RET) involved in computer nuclear holocaust war simulation modelling for the US military, so he's no dummie.

    It's a big subject that will have (in due time) huge implications for vessel propulsion......among other things!

    I'm personally of the opinion that MEGS coupled to plasmoidal induction hydrodynamic drive engines, will be the "future" for vessel propulsion...BUT I could be wrong!

    I guess only "time" will tell...

    In the mean "time" practice reciting what Tesla knew almost 100 years ago...

    That E=TC2 where T is delta T or change in time.

    If you care to really stretch the grey matter...resolve this.

    E=MC2 (Einstein)
    also
    E=TC2 (Tesla)

    Therefore,

    If
    E=MC2
    &
    also
    E=TC2

    Then it follows that

    MC2 = TC2

    Therefore it follows that

    M=T (where T is delta T or change in time)

    So, troutys theory of the space time continuum...

    Mass = Change In Time

    Ponder the implications of that for a wee while...I'll be asking 20 questions whenI get back!
    :D

    Cheers!
     
  10. lockhughes
    Joined: Jun 2002
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    lockhughes ElectricGuy

    Re: Joking? - moir? smatter of fact - no - I wuz deadly serious!

    http://www.prahlad.org/pub/bearden/patent_meg.htm
    http://www.cheniere.org/techpapers/Final Secret 9 Feb 1993/index.html
    M=T (where T is delta T or change in time)
    So, troutys theory of the space time continuum...
    Mass = Change In Time
    Ponder the implications of that for a wee while...I'll be asking 20 questions whenI get back!
    :D

    Thank you Trouty. Will read. How about a demo? Where are your prototypes? Any working models we can play with?
    Lock
     
  11. Guest

    Guest Guest

    Re: Solomon Technologies

    Hi Mike
    Ok. thanks!... Though I'm not sure what constitutes a "cycle" at this point, if the batteries are being almost constantly charged - shorepower,wind and solar, whether alongside or underway?
    I'm guessing that volts/#batteries/charging amps/etc can be optimized for the particular application - regular ferry service schedules, in this case. 1/2hr on, 1/2hr.off, etc.

    hehe... I won't count on THAT. But, I might bet, that our battery/ storage technologies will continue to improve in the years ahead, so this replacement/storage cost will continue to be driven down.

    Eliminated - for the ferry thingee anyway. The whole object of the (my) exercise is to get the fossil OUT of the boat!

    Mike, I'm guessing that you're referring to a charger that Solomon specs for their systems? Something onboard? If the charger were shoreside, I suppose there are more options, to get that faster charging...

    Sorry Mike - I don't "do" displacement anymore <grin>... Happy puttering around at 10-20knots under sail, on two hulls. Much of the materials I've read so far emphasize long/skinny as better for electrics. Would Portager gain from a double-ender/canoe/ fantail whatever hull? Or is the design "sawed-off"?

    Yeah! :)

    Thanks again Mike. Again, I'd be placing my hopes with improvements in storage/regenerative technologies... I've been trying to follow along on wind-generator technologies too, and expect these to improve as well. This one's pretty cute:
    http://www.marlec.co.uk/products/prods/rut503.htm

    Cheers
    Lock
     
  12. ewhel
    Joined: Jun 2002
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    Location: Maryland

    ewhel Junior Member

    Solomon Technologies

    Well folks, I wonder how many users run their 18HP Yanmar at 3,600 RPM's continuously(13.4KW). That's where it is rated at! Can you run it there continuously? Negative. What HP can you run it at continuously? (HINT...about about 15 for the first year or two) What is the hp load of a fully charged battery VS a partially charged battery that just started a diesel engine loaded with VHF, depth finder, radio and a couple lights turned on. Does Yanmar use those super efficient transmissions when selling product to Hunter, Catalina or J. ?
    I too was amazed when I took a 22hp diesel out of my boat and put a 10HP electric motor in and had significantly more power and response. It sent me back to the white board to calculate why. I found out that there is the advertised perfect world...and then there is reality. Our HP and efficiencies are Pure,not over stated, at the prop and will be the same 10 years from now as they are today. They push the prop directly without transmissions (except the Electric Wheel that uses a transmission only for slow speeds and it is frictionally eliminated a cruise).
    Battery Cycles...typically depleting the battery by 80% comprises one cycle....if you keep it above 50% you never cycle and that's what our diesel electric systems are designed to do. In an emergency you can go to 80% depletion by this is typically done. I have AGM's in my boat (the Casey on web site..1939 , 20,000 lb 28 footer) that have been there for 4 years with no degadation. We expect them to last for 6-8 years. What will you have done in maint on a diesel in 6-8 years....if you go to sea much you will have done 18-26 oil changes and filter changes, mabey a rebuild, mabey and new transmission, 6 transmission oil changes...and spent several hundred hours waiting for your diesel to warm up for 10 minutes so you can use it for 10 minutes...or even 5 minutes (10 minutes is Yanmar's suggested warm up time). I would much rather have a generator that always turns on runs at optimum efficiency...and oh by the way...where there was a 15-18HP yanmar , there can be a 4KW cacooned generator and 4Kw electric engine that you won't hear either running.
    Continuous Running....We have a boat(CAL 34) that regenerated it's way from Los Angeles to Tahiti....we have a Cheribini 44 that came to Maryland from England on 300 gals of fuel with Ice Maker, AC, Electric stove and oven, freezer and microwave all the way. We have a Conser 47 CAt that motored for 96 hours continuously and motor sailed from Florida to Maryland using the motors to increase speed and generate while sliding down waves. We also have a boat that uses wheel chair batteries and a 4kw generator which altogether is lighter than the comparable diesel engine. Our motors are powerful enough to stop a 20,000 lb 47 ft cat from 7.5knots to 0 knots in 35 feet and to accelerate that same cat to 7.5 knots in two boat lengths...this boat would have had twin 30HP diesels...it has twin 12hp Solomon Motors. The proof is in the pudding.
    P.S. I am not being petty...or arrogant....I am merely stating the facts as we have found them out. There is Ideal and Reality. I too was amazed at what our new inventions could do.I must go now but will return....you can always take a trip to Maryland and see for your self.
     
  13. Polarity
    Joined: Dec 2001
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    Polarity Senior Member

    Hi David and welcome to the site, glad you could make it!

    It certainly does look impressive and as you say the proof of the pudding...

    I would like to propose that what we may have here (any other Eliyahu M. Goldratt/Theory of Constraints http://www.goldratt.com/ fans out there?) is a problem with accepted measurements.
    The HP / BHP of a "drive unit" seems to have always been accepted as a reflection of the ability of that "drive unit" to move a boat through the water at a certain speed, and at certain speeds in differing conditions. If what you have said is accurate either

    a) there is a massive loss between the advertised rating of the engine and what comes out at the prop.
    or
    b) the measurement is wrong.

    My first thought was that the Ewheel suffers the same losses at the shaft as an engine. BUT I believe that friction increases with speed so if the prop has a bigger pitch/dia and therefore spins slower this would reduce this. BUT is that enough to explain the differences highlighted by David? - I am not so sure...

    Just maybe we should look at option b) .. is HP a totally inaccurate way to measure the effectiveness of an drive unit for a boat?

    What would an effective measurement consist of ?

    Fuel efficiency (consumption of joules/....x)
    noise
    weight of drive unit
    acceleration (apply f=ma to the above cat example)
    response to varying loads (ie waves)
    rpm of shaft
    what force generated, when...

    Gotta rush out and I will hack it around later, but if any mathematicians would like to pick up on this... :confused:


    Paul
     
  14. Portager
    Joined: May 2002
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    Portager Senior Member

    Re: Solomon Technologies

    Actually Diesels have multiple ratings. The most commonly used (and the two used by Yanmar) are the maximum power rating which can be maintained for a short period of time and the continuous power rating which can be maintained essentially indefinitely. Going to http://dieselmarine.com and looking up Yanmar engines you see that Yanmar has two current engines rates at 18 HP maximum, the 2GM20 http://dieselmarine.com/index.cfm?EID=030C0204 and the 2GM20F http://dieselmarine.com/index.cfm?EID=030C000F . The spec sheet for the 1,2 &3GM models is at http://www.yanmar.com/marine/pdfs2/123GM.pdf . Yanmar provides both the engine output power without marine gear and the propeller power output curve. This is also known as the propeller demand curve. This curve assumes that a fixed pitch propelled is designed to be fully loaded at the maximum engine speed. Therefore at lower speeds the propeller is under loaded and the curve shows the maximum power that the propeller can accept at this speed. If you provide more power, speed increases. This is the maximum power that any engine or motor can deliver to the water through the propeller at that speed. Using the Yanmar 2GM20 maximum continuous rated speed the engine can deliver 16 HP but the propeller can only accept 15 HP. This is true horse power delivered to the propeller.

    So what does that mean? Using the Greatheart 36 (designed by Michael Kasten) as an example (because I'm familiar with it and I know where to find the powering curves) http://www.xsw.com/gh36/
    Graphing the power curve data produces the attached graph. The data shows that at 10 HP the Greatheart 36 will maintain 5.8 knots but with 15 HP is can achieve about 6.35 knots. This shows that the 10 HP electric wheel can perform within 0.55 knots of the speed of the 15 HP diesel. Does this mean that the electric wheel has the same power as the diesel? No! It only shows that to go 1.17 times hull speed (defining hull speed as the square root of the length at the waterline in feet) requires 50% more power as it requires to go 1.07 times hull speed.

    I am sorry, but that is just not true! According to Northern Arizona Wind & Sun http://www.windsun.com/Batteries/Battery_FAQ.htm#Lifespan of Batteries , "A battery "cycle" is one complete discharge and recharge cycle." and "Battery life is directly related to how deep the battery is cycled each time. If a battery is discharged to 50% every day, it will last about twice as long as if it is cycled to 80% DOD. If cycled only 10% DOD, it will last about 5 times as long as one cycled to 50%."
    Here are the graphs that Concord provides for their Lifeline AGM batteries http://www.lifelinebatteries.com/graphs.asp . Click of the "Life Cycle Performace Against Leading Gel Cell Battery" graph.

    This is great, but it is not what I call continuous running. It is motor sailing and using regenerative charging. Basically using excess wind energy to recharge the batteries. This is fine for a sail boat that wants to sail most of the time, but what about a powerboat or a motor sailor that wants to run into the wind for an extended period of time.

    Continuing with the Greatheart 36 example. GH36 is 36' long and weighs 22,000 lbs fully loaded. Using the ST37 which costs $11,600 and provides 6 HP GH36 can achieve 5 knots at full power. The endurance at this power level is 2.9 hours (which by the way is 100% depth of discharge) so range is 14.5 Nmi. Using the twin ST37 costs $21,934 and provides 12 HP for a maximum speed of 6 knots. Endurance is 1.45 hr and range is 8.7 Nmi. Using the ST74 provides 12 HP and 6 knots speed (same as the twin ST37) and cost is $15,902. Endurance is 1.5 hr so range is 9 Nmi. Note, since you indicated that the batteries should not be discharged more than 50% these ranges should be cut in half. These ranges and speeds are adequate for exiting most harbors and getting to where you can switch to sail, but not much more.

    To provide continuous running then the generator would need to be large enough to maintain the power draw from the motor. For the single ST37 this is 36 amps X 144 volts = 5.184 kW. Using the 7 KW generator to provide some margin adds $11,750 to the cost of the ST37. If the generator were 80% efficient, this would require an engine with a continuous rating of 8.69 HP. With an 8.69 HP engine driving the prop GH36 could achieve about 5.6 knots versus the 5 knots with the ST37. For the ST74 the power load is 72 Amps X 144 volts = 10.368 kW. Using the 12 KW generator adds $13,750 to the cost of the ST74. The engine to drive the generator at 80% efficiency will require 17.4 HP. With a 17.4 HP engine driving the prop GH36 could achieve about 6.6 knots versus the 6 knots with the ST37.

    The Greatheart 36 would be powered by a 3JH3E engine which produces 36 HP continuous (40 maximum), providing a continuous speed is 7.5 knots. The retail cost of the 3JH3E with transmission is $10,447. Greatheart 36 is intended to use the alternator on the main engine to recharge the battery banks (as most sail boats do) so a generator is not required.

    Regards;
    Mike Schooley
     

  15. lockhughes
    Joined: Jun 2002
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    Location: Wards Island Toronto north shore, Lake Ontario

    lockhughes ElectricGuy

    vibration
    smell
    heat (loss)
    available environmental rebates on some taxes <grin>
    number of moving parts <hehe>
    which would young folks ask for, if you asked them which they'd prefer?
    whether any noise/smell/vibration/whatever bothers passengers?
    (makes `em feel ill)
    promotional value to a business, club or agency?

    Lock
     
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