# forget the springs, go with the electricity

D

#### [email protected]

Jan 1, 1970
0
stumbled across a powerpoint on the web, concise design analysis of
the problem by a professor of mechanical engineering. The equations
show why the patent-office file cabinets are littered with ideas for
spring-stored energy for bicycles which never saw a real factory
floor.... the energy-storage density just ain't there. His
recommendation: optimize the electrical approach.

Ok: who makes the best electrical-assist which encompasses an
efficient regenerative-braking?

what's the state of the art of energy-storage capacitors?

D

#### default

Jan 1, 1970
0
stumbled across a powerpoint on the web, concise design analysis of
the problem by a professor of mechanical engineering. The equations
show why the patent-office file cabinets are littered with ideas for
spring-stored energy for bicycles which never saw a real factory
floor.... the energy-storage density just ain't there. His
recommendation: optimize the electrical approach.

Ok: who makes the best electrical-assist which encompasses an
efficient regenerative-braking?

what's the state of the art of energy-storage capacitors?

Search on ultracapacitors lots of info.

I still like my cable/pulley idea better.

D

#### [email protected]

Jan 1, 1970
0
I still like my cable/pulley idea better.

ok, you do it on your mountain. maybe you have an angel giving you
capital at zero interest expense. i don't.

D

#### DougC

Jan 1, 1970
0
Ok: who makes the best electrical-assist which encompasses an
efficient regenerative-braking?

what's the state of the art of energy-storage capacitors?

I think the Bionx can do regenerative braking....

I don't think the electrical means would be the best solution however. I
have already found that the cost-per-mile of operating a Bionx is
greater than for operating a gasoline-engine of comparable power, and
that was assuming flat ground.

The problem with electrical vehicles is that everybody WANTS small
lightweight batteries, but they tend not to last very many discharges
before failing if they are deep-cycled, and if they aren't deep-cycled,
then you don't get much practical energy storage from them.

The only way to make electrical batteries that will last a lot of
discharge cycles is to make them lead-acid and make them BIG and only
ever discharge them lightly--but you see then,,,, if you want a vehicle
that can climb hills, then the last thing you want is a bunch of heavy

D

#### default

Jan 1, 1970
0
ok, you do it on your mountain. maybe you have an angel giving you
capital at zero interest expense. i don't.

Mountain topography and type of cargo aside . . . You figure high tech
state of the art is going to be less expensive than a piece of wire
and some pulleys? It won't take capital?

You wouldn't be the first person wanting to get a weight down a
mountain. Or hill - any mountain worth the name wouldn't be bicycle
friendly.

I worked a place in Alaska where we wanted to haul supplies up to a
mountain lookout, and do it cheaply. We had a very steep cliff face
and they were using airlifted supplies. Some guy got the idea to use
a rope and buckets. Water filled a bucket and pulled the supplies up
in another bucket. Daily re supply with food and equipment versus
weekly and at a lot lower cost.

Still needed the copter for changing observers, and no one could take
more than a month in the 5 X 8 aluminum box they called home. They
were working on a steel cable to lift men up. The idea was to put one
guy in a sling at the base another at the top, add enough water to
bring the up guy down (if necessary). Plan was to use something like
the old style dial telephones - centrifugal brake to regulate the
speed - or an off the shelf centrifugal clutch from a riding
lawnmower. I never saw that working, but have no doubt they could
make it work.

P

#### Paul E. Schoen

Jan 1, 1970
0
stumbled across a powerpoint on the web, concise design analysis of
the problem by a professor of mechanical engineering. The equations
show why the patent-office file cabinets are littered with ideas for
spring-stored energy for bicycles which never saw a real factory
floor.... the energy-storage density just ain't there. His
recommendation: optimize the electrical approach.

Ok: who makes the best electrical-assist which encompasses an
efficient regenerative-braking?

what's the state of the art of energy-storage capacitors?

I had a similar idea to build a small railway on my property which would be
used to bring down firewood from the top of a hill (about 50' elevation). I
figured I could run it for free, or maybe get extra energy, by using the
potential energy of the wood. Probably it would not be economically worth
the effort, but the cool fun factor made it something I wanted to try.
Having batteries in the vehicle seemed to be a null factor, except that it
required bigger motors or slower gearing, and maybe more rolling
resistance. I also considered electrifying the rails, or using an overhead
hot line, but it would only be efficient at voltages much higher than would
be safe.

For energy storage capacitors, try:

http://www.maxwell.com/ultracapacitors/index.asp

From a previous post, here is a discussion of what to expect:

Energy storage for the capacitors is based on 1/2*C*V^2, so your 210,000 uF
25 V bank will store 65 J (watt-seconds). If you have 800 watts of motors
(1 HP), the energy will power the vehicle for less than 0.1 seconds. They
are most useful for quick energy dumps from dynamic braking, but you will
need more than that to absorb the kinetic energy of a fast stop.
Supercapacitors are available, such as Maxwell BPAP1200 – E270, which are
1200 F at 2.7 V. Ten in series gives you 120 F at 27 volts, and energy
storage of 43,000 W-Sec, or 50 seconds run time at 800 watts. They cost
about $46 each. Some interesting high surge current capacitors are: http://www.sbelectronics.com/images/PDFs/Power_Ring_Options_0207.pdf Paul L #### landotter Jan 1, 1970 0 Google answers many questions, if you're just PATIENT enough. just stumbled across a powerpoint on the web, concise design analysis of the problem by a professor of mechanical engineering. The equations show why the patent-office file cabinets are littered with ideas for spring-stored energy for bicycles which never saw a real factory floor.... the energy-storage density just ain't there. They obviously haven't seen the proper way to do this...with a really big rubber band, like in the Swedish film, "The Apple War". http://en.wikipedia.org/wiki/The_Apple_War I wish I had screenies, but basically the bicycle guy in the film uses the rubber band to get to the bus stop really fast, and stretches it on the way home in the evening. A #### A Muzi Jan 1, 1970 0 I still like my cable/pulley idea better. ok, you do it on your mountain. maybe you have an angel giving you capital at zero interest expense. i don't. And we've all seen 'Zorba the Greek' with the wire guided logs. H #### Homer J Simpson Jan 1, 1970 0 And we've all seen 'Zorba the Greek' with the wire guided logs. I've also seen that work OK. -- .. -- .. .. .. .. .. .. .. .. -- R #### Rich Grise Jan 1, 1970 0 I had a similar idea to build a small railway on my property which would be used to bring down firewood from the top of a hill (about 50' elevation). I figured I could run it for free, or maybe get extra energy, by using the potential energy of the wood. Probably it would not be economically worth the effort, but the cool fun factor made it something I wanted to try. Having batteries in the vehicle seemed to be a null factor, except that it required bigger motors or slower gearing, and maybe more rolling resistance. I also considered electrifying the rails, or using an overhead hot line, but it would only be efficient at voltages much higher than would be safe. So, how did it work out? What did you finally end up with? Thanks, Rich C #### ctyankee Jan 1, 1970 0 I had a similar idea to build a small railway on my property which would be used to bring down firewood from the top of a hill (about 50' elevation). I figured I could run it for free, or maybe get extra energy, by using the potential energy of the wood. Probably it would not be economically worth the effort, but the cool fun factor made it something I wanted to try. Having batteries in the vehicle seemed to be a null factor, except that it required bigger motors or slower gearing, and maybe more rolling resistance. I also considered electrifying the rails, or using an overhead hot line, but it would only be efficient at voltages much higher than would be safe. For energy storage capacitors, try: http://www.maxwell.com/ultracapacitors/index.asp From a previous post, here is a discussion of what to expect: Energy storage for the capacitors is based on 1/2*C*V^2, so your 210,000 uF 25 V bank will store 65 J (watt-seconds). If you have 800 watts of motors (1 HP), the energy will power the vehicle for less than 0.1 seconds. They are most useful for quick energy dumps from dynamic braking, but you will need more than that to absorb the kinetic energy of a fast stop. Supercapacitors are available, such as Maxwell BPAP1200 - E270, which are 1200 F at 2.7 V. Ten in series gives you 120 F at 27 volts, and energy storage of 43,000 W-Sec, or 50 seconds run time at 800 watts. They cost about$46 each.

Some interesting high surge current capacitors are:

http://www.sbelectronics.com/images/PDFs/Power_Ring_Options_0207.pdf

Paul

1200F @ 2.7 V -- that's not a capacitor! It's a rechargable hearing
aid button cell <g>

Y

#### YD

Jan 1, 1970
0
They obviously haven't seen the proper way to do this...with a really
big rubber band, like in the Swedish film, "The Apple War".

http://en.wikipedia.org/wiki/The_Apple_War

I wish I had screenies, but basically the bicycle guy in the film uses
the rubber band to get to the bus stop really fast, and stretches it
on the way home in the evening.

Yeah, a big bunch of bungee cords can't be all that expensive. Needs a
rather straight stretch of road, though.

- YD.

M

#### Michael A. Terrell

Jan 1, 1970
0
YD said:
Yeah, a big bunch of bungee cords can't be all that expensive. Needs a
rather straight stretch of road, though.

Use a pack mule. Its what they were created for.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

L

#### Lostgallifreyan

Jan 1, 1970
0
Supercapacitors are available, such as Maxwell BPAP1200 – E270, which are
1200 F at 2.7 V. Ten in series gives you 120 F at 27 volts, and energy
storage of 43,000 W-Sec, or 50 seconds run time at 800 watts. They cost

Do you have a link to more on those?

B

#### BobG

Jan 1, 1970
0
Do you have a link to more on those?
==================================
Search for Maxwell Technologies Boostcap

L

#### Lostgallifreyan

Jan 1, 1970
0
==================================
Search for Maxwell Technologies Boostcap

Thankyou. Those look good.

F

#### Frithiof Andreas Jensen

Jan 1, 1970
0
I had a similar idea to build a small railway on my property which would
be used to bring down firewood from the top of a hill (about 50'
elevation). I figured I could run it for free, or maybe get extra energy,
by using the potential energy of the wood.

Maybe you should try with a fly-wheel first?

A

#### Anthony Matonak

Jan 1, 1970
0
Paul E. Schoen wrote:
....
I had a similar idea to build a small railway on my property which would be
used to bring down firewood from the top of a hill (about 50' elevation). I
figured I could run it for free, or maybe get extra energy, by using the
potential energy of the wood. Probably it would not be economically worth
the effort, but the cool fun factor made it something I wanted to try.
Having batteries in the vehicle seemed to be a null factor, except that it
required bigger motors or slower gearing, and maybe more rolling
resistance. I also considered electrifying the rails, or using an overhead
hot line, but it would only be efficient at voltages much higher than would
be safe.

I would think the coolest method to use the potential energy of the wood
to run the railway would be to burn it in a steam engine.

Seriously though, I've seen small "railroads" in shopping malls that are
run off 12V running through the rails. They're big enough to carry a
bunch of kids so something similar should be able to lug a cartload or
two of firewood. It doesn't have to be terribly efficient to be useful.
Slow is also probably quite acceptable. If it saves you from having to
make several trips then it can be quite slow and yet still faster than
the alternative.

You could even go all renewable on this and fit out solar panels on the
top of the "engine" for this railroad. When the sun shines the thing
will slowly work its way up the hill using whatever energy the panels
produce. Add a stop switch at the top (of course) to keep it from going
too far. So what it if takes a day or two to get there? It's not like
you would have to be driving.

Anthony

Replies
65
Views
3K
D
Replies
15
Views
2K
yaputya
Y
N
Replies
12
Views
1K
Dr. Anton T. Squeegee
D
D
Replies
0
Views
1K
Dave Pyles
D
J
Replies
0
Views
793
Jamie
J