If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #2941
Joined: Fri Jun 25 2010, 08:08AM
Location:
Posts: 143
I get across this link : obviously it's not a nuclear reactor and it have a limited use but I like the concept ,a power cell base on this idea could reload batteries in very improbable location:like the catacomb of Paris, or be use to power a small beacon for very long time... I try to match the color from the phosphor to an absorption pick from different type of solar cell.does any one have some idea about it?
Registered Member #27
Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058
Most solar cells are very inefficient at low power levels so you need to hunt out one that is good for this application. Some low efficiency polycrystalline cells used in garden lamps keep their efficiency at low light and are more efficient than common high efficiency cells for this sort of thing.
You should probably concentrate on getting as much light as possible on to the cell at the highest concentration you can before considering the wavelength.
Registered Member #2941
Joined: Fri Jun 25 2010, 08:08AM
Location:
Posts: 143
do you mean that the input vs output of solar cell is not linear? I know that amorphous silicon cell work great in low light situation but there efficiency is very small (10/100?) I south the difference came from the fact that outside ,when the light goes down ,the spectrum shift to the red,making low wavelength cell more efficient.
I found some tritium exit sign for 300 euro a piece on Internet ,they contain 5 vial of 25 cm long in it,my idea was to space them of 0.5 cm and to have two solar cell ,one on each side,with the tube in the middle...the efficiency will be small anyway but having a perfect match in between the light wavelength and the semiconductor gap should help...
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062
Did you try using a ceramic capacitor in parallel with the cell?
this ought to charge up slowly with even nanoamps of current.
Also, IIRC your average cheap silicon solar cell is appallingly inefficient at green wavelengths. You might be better off with a large area red LED such a Luxeon emitter, the efficiency of these can be pretty high as I have tested this with smaller diodes..
see
I did wonder if an interesting hack would be to find a large area emitter such as one from a surplus 1980's era calculator, parallel connect the diodes and install the tritium tube over it being careful not to damage the diode interconnects.
A bubble concentrator lens would increase the efficiency though, perhaps use the existing one from the calculator?
Registered Member #2941
Joined: Fri Jun 25 2010, 08:08AM
Location:
Posts: 143
no I didn't try ceramic cap ,but that's a good idea,for the rest ,some semiconductor must work better than some other (depending on the gap)using led as receiver can help to determine it . I don't like the idea to use some light concentrator with tritium light source ,because this type of light is already very diffuse ,having a direct light path should work better.
Registered Member #2893
Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242
I think a betavoltiac could be a better option...
3H emits beta paticles at an enegy of about 5keV, so if I am correct you'd need 6241000000000000000 decays in one second to make 1 ampere of current provided you capture all those beta particles. My 6" tritium lamp has an activity of only about 67gigabecquerels, so only 67,000,000,000 electons ae emitted a second: that's 10 nanoamps. Since tritium costs $50K an ounce it would cost quite a lot to make a 5kV 1A betavoltiac... so a tritium powered item isn't exactly economical.
Registered Member #2941
Joined: Fri Jun 25 2010, 08:08AM
Location:
Posts: 143
Grenadier wrote ...
I think a betavoltiac could be a better option...
3H emits beta paticles at an enegy of about 5keV, so if I am correct you'd need 6241000000000000000 decays in one second to make 1 ampere of current provided you capture all those beta particles. My 6" tritium lamp has an activity of only about 67gigabecquerels, so only 67,000,000,000 electons ae emitted a second: that's 10 nanoamps. Since tritium costs $50K an ounce it would cost quite a lot to make a 5kV 1A betavoltiac... so a tritium powered item isn't exactly economical.
Just my $0.02
I suppose a 5kw generator witch would be noise less ,caring 10 year of carburant and requiring no maintenance at all could have some interesting application but I am only interested by much smaller amount of power ,10's of a what would be very nice already,I like the idea of power-source witch would defied man time scale ,like a camera taking picture of a valley every days for 10 or 20 year(very poetics interest)also the perspective of having daily life object witch would not need battery replacement and who would stay operational no matter what .
however ,you are right ,beta-voltaic cell would be much more efficient ,I suppose it could be possible to use 2 mono-crystalline solar cell very close to each other and to let a bit of tritium in between,but I doubt the efficiency would be high ,as the cell itself would generate very low voltage.is there a set up hitch make it possible to use the 5kev as to get a 5kv output from the cell ? is it possible that in cell with low band gap like silicone cell ,the beta particle trigger the relize of more than one electron?
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
tritium fotovoltaic generator
