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Date: 05 Jul 2006 17:24:24
From: Doug Goncz
Subject: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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Hello, news:alt.rec.bicycles.recumbent readers!
I have been working on a self-recharging human electric hybrid bike for
five years now and the latest version is in an interesting state of
development. You take a motor driven by pedals or road and connect it
in parallel with an ultracapacitor bank to form an "electric flywheel"
simulating the action of a mechanical flywheel with fluid clutch, but
at much lower weight. The R*I^2 losses are analogous to slip in a fluid
clutch.
My current setup is the Wilderness EV electric front hub and eight
Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
store over 50 kilojoules of energy. I will extend the pack to twelve,
and possibly sixteen caps some day soon. It's got More Power!
I've been writing about it in news:sci.physics.research.
Any Washington, DC are bent riders are welcome to take a spin on any
dry day.
Doug Goncz
Replikon Research
Seven Corners, VA 22044-0394
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Date: 08 Sep 2006 04:15:49
From: The Dougster
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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dlhii wrote:
> "Doug Goncz" <DGoncz@aol.com> wrote:
>
> >
> >My current setup is the Wilderness EV electric front hub and eight
> >Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
> >store over 50 kilojoules of energy. I will extend the pack to twelve,
> >and possibly sixteen caps some day soon. It's got More Power!
> >
>
> Not being an electronic wiz, how do you regulate the draw down of the
> Caps. The only thing I am familiar with it the start caps for motors.
> All at once....
>
> Don
I am now running 12 caps.
Draw down?
Sorry I missed Mads's post.
Mads wrote:
>Hi Doug
>That is very interesting.
>At the risk of being considered dull, I would like to ask how this is from
>a safety perspective? What happens if a truck runs over your capacitors,
>when they are fully charged? Do they release all their energy at once?
They can put 4500 A into a short, one reference claims. Another claims
650 A. The internal resistance is 0.001 ohm. At 4500A, that's 4.5 W of
internal dissipation, not considered a hazard at this point. They can
do this 100,000 tims, unlike a battery.
>What happens if the capacitors short circuit? From another post, I can see,
>that there resistance is extremely low, so I would guess they could cause
>an explosion if you short circuited them.
I've set the rack back on fire before with a short, but I have
procedures to manage that now. Using nylon M6x1 screws could help. It
was only a *small* fire.... :) But they don't provide megawatt shorts
like electrolytic caps do. No "bang" when you discharge into a short.
You can weld with this pack.
>Could/is the use of capacitors as safe as a conventional chemical battery
>(just a hole lot more efficient)?
Well, it can be managed. Another reason is end of life. No lead into
the enivronment, but there is acetonitrile, which can be recycled. With
such a long life, the end of life picture is pretty good. Charge
acceptance is superior to battery as internal resistance is low.
Performance will be spectacular when RTS becomes available. A chemical
battery just isn't suitable for a RTS source.
Mads Lindstr=F8m
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Date: 06 Sep 2006 13:04:00
From: dlhii
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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"Doug Goncz" <DGoncz@aol.com > wrote:
>
>My current setup is the Wilderness EV electric front hub and eight
>Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
>store over 50 kilojoules of energy. I will extend the pack to twelve,
>and possibly sixteen caps some day soon. It's got More Power!
>
Not being an electronic wiz, how do you regulate the draw down of the
Caps. The only thing I am familiar with it the start caps for motors.
All at once....
Don
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Date: 19 Jul 2006 16:09:54
From: codeman
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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Hi Doug
Doug Goncz wrote:
> Hello, news:alt.rec.bicycles.recumbent readers!
>
> I have been working on a self-recharging human electric hybrid bike for
> five years now and the latest version is in an interesting state of
> development. You take a motor driven by pedals or road and connect it
> in parallel with an ultracapacitor bank to form an "electric flywheel"
> simulating the action of a mechanical flywheel with fluid clutch, but
> at much lower weight. The R*I^2 losses are analogous to slip in a fluid
> clutch.
>
> My current setup is the Wilderness EV electric front hub and eight
> Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
> store over 50 kilojoules of energy. I will extend the pack to twelve,
> and possibly sixteen caps some day soon. It's got More Power!
>
> I've been writing about it in news:sci.physics.research.
>
> Any Washington, DC are bent riders are welcome to take a spin on any
> dry day.
>
> Doug Goncz
> Replikon Research
> Seven Corners, VA 22044-0394
That is very interesting.
At the risk of being considered dull, I would like to ask how this is from
a safety perspective? What happens if a truck runs over your capacitors,
when they are fully charged? Do they release all their energy at once?
What happens if the capacitors short circuit? From another post, I can see,
that there resistance is extremely low, so I would guess they could cause
an explosion if you short circuited them.
Could/is the use of capacitors as safe as a conventional chemical battery
(just a hole lot more efficient)?
Mads Lindstrøm
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Date: 08 Jul 2006 07:00:42
From: Doug Goncz
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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Hi, there.
aorange wrote:
> tesla would be proud! i am curious. my newest effort seems bulky and
> inefficient by comparison. pedal/generator/batteries[150ah]/motor[24v]
> [in canada up to 500w max] on 350 suzuki quad front end/400cc yamaha
> bike reardrive. built for comfort!
> i wish to incorporate more lightweight power storage. do you have a
> web site?
Just ftp://users.aol.com/DGoncz
Have a look around in Bicycle and MotorGenerator directories.
Elsewhere, also.
Doug
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Date: 07 Jul 2006 20:03:26
From: aorange
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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tesla would be proud! i am curious. my newest effort seems bulky and
inefficient by comparison. pedal/generator/batteries[150ah]/motor[24v]
[in canada up to 500w max] on 350 suzuki quad front end/400cc yamaha
bike reardrive. built for comfort!
i wish to incorporate more lightweight power storage. do you have a
web site?
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Date: 06 Jul 2006 16:36:47
From: Doug Goncz
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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Ron Wyckoff wrote (and I am replying to):
> Doug Goncz wrote:
> > Hello, news:alt.rec.bicycles.recumbent readers!
> >
> > I have been working on a self-recharging human electric hybrid bike for
> > five years now and the latest version is in an interesting state of
> > development. You take a motor driven by pedals or road and connect it
> > in parallel with an ultracapacitor bank to form an "electric flywheel"
> > simulating the action of a mechanical flywheel with fluid clutch, but
> > at much lower weight. The R*I^2 losses are analogous to slip in a fluid
> > clutch.
>
> Very interesting, what do you calculate the total efficiency to be.
At around 7.5 V, the free running current is around 300 ma. The bearing
drag is around 2W. Chain drive is about 98% at 80 W in middle gear.
2/80 is about 3%. So, *if you aren't storing power*, the drive
efficiency is around 98% - 3% = 95%.
If you are storing or using power there are R*I^2 losses. The system is
very stiff; I found that on my latest 5 mile ride I was able to keep up
a cooling breeze better than on similar days with no such drive
installed. However, the losses are noticeable on hlls. I stored 110 W
for around 15 sec on a local small hill, but at considerable loss of
kinetic energy gain. All this remains to be measured. I have an
application to NI.com to fill in to have them grant my school a DAQ
module I can use while mobile to get better data on efficiency. It's a
$600 module; Compact Flash DAQ.
> Even Toyota can manage
> only about 40% efficiency in regeneration in their Prius.
This would be better because it's almost always near peak efficiency.
How much better, I have to measure.
> I'll be
> working on an electric assist recumbent tandem, and I am intriqued
> about getting rid of the awfully long chain drive of the
> typical bent Tandem. Seems like a small 200W generator would be a lot
> lighter. Then switch it over to a rowing motion, for whole body
> workouts.
The generator constant is 80 volts per mph. The resistance is somewhere
between 2 and 5 ohms. The series resistance of the caps is (wowee)
0.008 ohms. It could be worked out.
Are you thinking pedal to generator to wire to battery to wire to motor
to chain to hub? Interesting! Is that the "series" configuration?
That's not how mine works.
Mine is pedal to hub, road-coupled to motor/generator to and from the
cap bank. One advantage of that is you get 2WD which if the caps are
really charged is enough to augment your dirt-path hillclimbing beyond
human ability. A disadvantae is no stopped pedaling.
I've never charged the caps that far. With the 12 or 16 cap bank, that
will be more likely to happen as the series capacitance will be less,
not more.
I still worry about the release of acetonitrile with an overcharge.
It's a solvent in the caps; exposure can cause cyanosis. Erk. I don't
want that, so I run them gently.
> >
> > My current setup is the Wilderness EV electric front hub and eight
> > Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
> > store over 50 kilojoules of energy.
>
> That would be about 14whr, or about 12mph for 30min? 20mph for 12min.
> Not bad actually. How much are the Caps?
Cost? Around $35 each surplus when I bought them. Now in the $20 range
surplus, close-out.
>
> I will extend the pack to twelve,
> > and possibly sixteen caps some day soon. It's got More Power!
> >
> > I've been writing about it in news:sci.physics.research.
>
> I'll have to check your posts there, thanks.
>
> >
> > Any Washington, DC are bent riders are welcome to take a spin on any
> > dry day.
> >
> > Doug Goncz
> > Replikon Research
> > Seven Corners, VA 22044-0394
>
> Ron
Many thanks for showing interest Ron. Where are you at, localitywise?
Doug
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Date: 06 Jul 2006 15:19:28
From: Ron Wyckoff
Subject: Re: Self-Recharging Ultracapacitor Lightning Thunderbolt Recumbent
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Doug Goncz wrote:
> Hello, news:alt.rec.bicycles.recumbent readers!
>
> I have been working on a self-recharging human electric hybrid bike for
> five years now and the latest version is in an interesting state of
> development. You take a motor driven by pedals or road and connect it
> in parallel with an ultracapacitor bank to form an "electric flywheel"
> simulating the action of a mechanical flywheel with fluid clutch, but
> at much lower weight. The R*I^2 losses are analogous to slip in a fluid
> clutch.
Very interesting, what do you calculate the total efficiency to be.
Even Toyota can manage
only about 40% efficiency in regeneration in their Prius. I'll be
working on an electric assist recumbent tandem, and I am intriqued
about getting rid of the awfully long chain drive of the
typical bent Tandem. Seems like a small 200W generator would be a lot
lighter. Then switch it over to a rowing motion, for whole body
workouts.
>
> My current setup is the Wilderness EV electric front hub and eight
> Maxwell Technologies PC2500 caps rated 2.5 V, 2700 F each. The rig can
> store over 50 kilojoules of energy.
That would be about 14whr, or about 12mph for 30min? 20mph for 12min.
Not bad actually. How much are the Caps?
I will extend the pack to twelve,
> and possibly sixteen caps some day soon. It's got More Power!
>
> I've been writing about it in news:sci.physics.research.
I'll have to check your posts there, thanks.
>
> Any Washington, DC are bent riders are welcome to take a spin on any
> dry day.
>
> Doug Goncz
> Replikon Research
> Seven Corners, VA 22044-0394
Ron
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