This idea builds upon some existing half-baked ideas, but with two important twists:
1. It uses DU, which is a very dense material.
2. It adds the concept of peak time/off-peak time.
First, by using counterweights, the amount of electrical energy uses to raise and lower elevators should be reduced. I'm going to basically have to hand-wave through this point, the design will be more complex than current elevators, but basically, when people go up, counterweights go down, when people go down, counterweights go up, and, if possible, design the elevators so that people can counterweigh each other, that is, a carload of people going down helps lift the carload going up.
The counterweights will be dynamic, i.e., if only one person is on the elevator, less counterweight is used, or the counterweight is geared to a kind of pulley system so that it doesn't drop as far as the elevator is raised.
The counterweights in question will have to be quite heavy, after all, if there are, say 100 people that go to the top floor, and each weighs 200 lbs, we are talking about 10 tons of counterweights. And this pattern would be repeated for every floor.
One of the heaviest substances known to man is depleted uranium. Sure, it's radioactive, but a nice coating of lead (which is also heavy) will dampen the radiation quite nicely. Perhaps additional layers will be called for, i.e, ceramics, plastics, etc, but the radiation can be safely blocked. The new market for DU will reduce the temptation (and availability) to turn DU into armor piercing bullets, etc, where the radioactivity will actually matter. Bullets will chip, burnoff, etc, much moreso than a chunk of DU packed in a nice lead sheath, put to work in elevators.
The final piece of this puzzle is the concept of peak/off-peak hours. Obviously, no machine is perfect, and there will be losses of stored potential energy over the course of the day. But, in some markets, electrical energy is much cheaper during off-peak hours, i.e. 3 a.m. at night when everyone is sleeping.
And this would be when the counterweight system is automatically reset so that all the counterweights are at maximum height, ready for the morning traffic.-- Madai, Aug 24 2005 Idea being built on CTV_20elevator [Madai, Aug 24 2005] a link related to peak hours http://www.coned.co...rgyresvoluntary.asp [Madai, Aug 24 2005] Depleted uranium, twice as dense as lead http://www.who.int/...actsheets/fs257/en/ [Madai, Aug 24 2005] Hazards of Depleted Uranium http://www.iacenter...pleted/duupdate.htm [DrCurry, Aug 24 2005] Smoke Detectors, and other radioactive fun http://flatrock.org...dioactive_items.htm [Madai, Aug 24 2005] Tungsten rollercoaster http://minerals.usg...tungsten/680798.pdf [Madai, Aug 24 2005] Why is everyone so intent on using depleted uranium in household settings? It may no longer be up to powering a nuclear reactor, but it's still very radioactive - look at the problems Iraqis and ex-servicemen have been having. One glowing green fishbone.-- DrCurry, Aug 24 2005 Most elevators already use counterweights, no? Except for hydraulic ram elevators, which appear to be limited to a few floors. What's the advantage here?-- oxen crossing, Aug 24 2005 DrCurry, do you under the huge gaping gap between using DU as BULLETS (which loose up to 40% of their mass when fired, according to your link) and using them as counterweights heavily shielded in lead? I agree with you that DU kitchen knives are a bad idea. The big difference between my idea and the kitchen knife idea is that the uranium will be heavily coated, and no radiation can escape unless the lead coating is melted off.
Depleted uranium behind lead is safer than the x-rays you get at the dentist.
And Oxen, the advantages are: DU is denser, so it can lift more people per volume, and there's tons of it sitting around looking for a market, and finally, every DU elevator prevents the manufacture of thousands of radioactive bullets.-- Madai, Aug 24 2005 The high density/weight and the off-peak reset are great. You would still have radioactivity, still need a special license to handle and distribute, and still need to post notices if you purposely added radioactive material to a building. Which means that even if the idea were perfect,the public's perception of these elevators may still be quite negative.-- sleeka, Aug 24 2005 The public will have to be educated, yes. As for "purposely adding radioactive material to a building", hi hi smoke detectors.-- Madai, Aug 24 2005 A rather minimal idea, substituting one material for another. Actually...hell...it's no idea at all. I'd MFD it, but I'm waiting for Madai to explain the other part of the idea, using people as counterweight for people. How does that work? Or did he even think about it?(BTW, DU counterweights are used in military aircraft, where it might actually make sense, because of the limited space available.)-- ldischler, Aug 24 2005 ldischler, the process of using people to counterweigh each other will be complicated to implement in an elevator, but not beyond human ingenuity. The principle of humans being counterweights for each other can be found on most playgrounds: they are called seesaws.
As for how to make it work, well, I'm no mechanical engineer. Perhaps a gear system not unlike that found on a multi-speed bike, perhaps a liquid medium to efficiently transfer the energy to allow it to do work.
Space may be especially limited on an aircraft, but reducing the amount of space used(or increasing the efficiency of said space) is a bonus no matter where you can reduce space.-- Madai, Aug 24 2005 So...regenerative braking on one car as it goes down, to partially power the motor of another car as it goes up. That way each can start and stop independently. Something like that, right?-- ldischler, Aug 24 2005 Some form of regenerative braking, yes. Probably not electric regenerative braking, 30% inefficiency can probably be beaten by a mechanical/hydraulic/etc system. Of course, elevators do not need the same type of brakes car do, as they do not have the same acceleration/decelleration characteristics.-- Madai, Aug 24 2005 //hi hi smoke detectors.// Indeed. I guess I meant a very large amount of radioactive material, in a completely new situation where one couldn't necessarily show that the benefits outweigh potential dangers, however minute. It's easy for the public to convince itself it was misled.-- sleeka, Aug 24 2005 They could design the system to be able to used either DU, Lead, Iron, or concrete/gravel-filled weights.
Here's the densities in in g/cm3:
Substance Density in g/cm3 Iridium 22.65 Osmium 22.61 Platinum 21.45 Gold 19.30 Tungsten 19.25 Uranium 19.05 Mercury 13.58 Palladium 12.023 Lead 11.34 Silver 10.49 Copper 8.92 Iron 7.87 Tin 7.31 Titanium 4.507 Diamond 3.5 Aluminium 2.7 concrete 2.3 Magnesium 1.74 Seawater 1.025 Water 1.000
Then cross reference cost per ton:
Uranium: Potentially free, if laws are written that way.(currently, it's given away free to arms manufacturers) Tungsten Lead: $1000+/ton Iron: $100+/ton Concrete: $28+/ton Tungsten: $5000+/ton
Nm, I misread tungsten prices, they sell it $45 per 8kg, not $45 per ton. Yikes.-- Madai, Aug 24 2005 Oops, misread. Thought this was DUI elevators. Never mind.-- normzone, Dec 16 2007 random, halfbakery