Post by thread:[EE:] Source for small Solar pannels

Hello i am looking for a while, for a source for small solar panels. For small, i mean low power and credit card size +-. Something around 6V peak @ 50mA would be great! Stacking of low voltage very small pannels would be great either. I would like to hear your thought, ideas and hints! Thanks very much Antonio Sergio Sena --------------------------------------------- Antsnio Sirgio Sena (Field Applications Engineer) Primetec - Engenharia de Sistemas, Lda. Rua Porto Alegre, 9 - 1: Esq. 2780-031 Oeiras PORTUGAL e-mail: spam_OUTasenaTakeThisOuTprimetec.pt WEB: http://www.primetec.pt . -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

?i am looking for a while, for a source for small solar panels. > >For small, i mean low power and credit card size +-. Hmm, I take it from your email address (.pt) that you are in Portugal. I would suggest you try RS Components and check catalogue numbers 194-098, 194-127, 194-133 and 194-149. See rshttp://www.com or try Farnell or Conrad for similar items. A couple of these numbers I have quoted are supplied to RS by BP Solar, so it may be worth while contacting them. I know that RS was one of the recommended suppliers for the Robot Challenge that the BBC ran late last year, but have no experience with the product itself. Another option may be just to butcher a solar powered calculator, depending how many you want. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

> i am looking for a while, for a source for small solar panels. > > For small, i mean low power and credit card size +-. > > Something around 6V peak @ 50mA would be great! > Stacking of low voltage very small pannels would be great either. That's a very modest requirement - 300 mW peak. If this is fro one off or small volume jobs then calculator or hobbyist panels would probably be suitable. These are liable to be amorphous silicon which have significantly lower efficiencies and lower lifetimes so the application may affect what you do. You get about 500 mV peak per cell so you are going to need 12 cells. You can stack individual cells yourself but it becomes very cost ineffective to do so. You could consider using a smaller voltage unit (say 2 volts) with a stepup converter. Using fewer larger cells may make it appropriate to series connect 4 cells that are better suited to your application. A converter IC intended to run on a single alkaline cell would work with this. Russell McMahon -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

In fact the 194-098 model, is +- what im looking for. The cells it self. But less voltage, around the same voltage. Having work with RS before, i know that they have higher prices than other distributers. Yep i know BP Solar, i have some panels made by them. They work great so far. Big ones, around 50W. Enough juice to power my radios at the shack! Alan, thanks for the hint! Antonio Sergio Sena > ?i am looking for a while, for a source for small solar panels. > > > >For small, i mean low power and credit card size +-. > > Hmm, I take it from your email address (.pt) that you are in Portugal. I > would suggest you try RS Components and check catalogue numbers 194-098, > 194-127, 194-133 and 194-149. See rshttp://www.com or try Farnell or Conrad > for similar items. A couple of these numbers I have quoted are supplied to > RS by BP Solar, so it may be worth while contacting them. I know that RS was > one of the recommended suppliers for the Robot Challenge that the BBC ran > late last year, but have no experience with the product itself. > > Another option may be just to butcher a solar powered calculator, depending > how many you want. > > -- -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

> > i am looking for a while, for a source for small solar panels. > > > > For small, i mean low power and credit card size +-. > > > > Something around 6V peak @ 50mA would be great! > > Stacking of low voltage very small pannels would be great either. > > That's a very modest requirement - 300 mW peak. > If this is fro one off or small volume jobs then calculator or hobbyist > panels would probably be suitable. These are liable to be amorphous silicon > which have significantly lower efficiencies and lower lifetimes so the > application may affect what you do. You get about 500 mV peak per cell so > you are going to need 12 cells. You can stack individual cells yourself but > it becomes very cost ineffective to do so. > > You could consider using a smaller voltage unit (say 2 volts) with a stepup > converter. Using fewer larger cells may make it appropriate to series > connect 4 cells that are better suited to your application. A converter IC > intended to run on a single alkaline cell would work with this. > > > Russell McMahon > > -- Im going to use the cells to give enough power to compensate for leakage currents of the battery, and to power the circuits during day time. While doing very low charging. Yes, im using a very low power stepup converter. The average power i spend per day is never higher than 15mA, maybe 20mA. Sometimes less than 10mA. Depends on the need the user has of the circuit. Antonio Sergio Sena -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Hello David, ill be looking to have that power at peak day light, on a good summer day :) As i said on a previous email, the pannels are almost to do some energy Scavenging from the environment. This case, sun light. Need to compensate for battery self discharge, and to low low charge the batteries i have. Using a low power setup also. Whats your idea ? Antonio Sergio Sena > Antonio, > Under what light source/intensity are you looking for 6V peak at 50mA? > > Dave > > Something around 6V peak @ 50mA would be great! > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

I didn't know what your application was, I just knew that rated output is usually in full sunlit conditions. If you were planning on using panels indoors, you'd be sorely disappointed with their output. I'd buy whatever you can from the surplus market and make a 'charge controller' do the battery charging/maintenance for you. FWIW, I ran 8 Siemens 55W panels through a Trace C40 charge controller to 880AH 12V golf cart battery array to an Exeltech XP1200 inverter for a few years. Dave -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

>I didn't know what your application was, I just knew >that rated output is usually in full sunlit conditions. >If you were planning on using panels indoors, you'd be >sorely disappointed with their output. Heh, yeah, the BBC robots contest I mentioned, for the solar section, they had the cars sitting on the start line, and then to start them turned on a huge bank of floodlights along the length of the track. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Indeed what you say is true. I had the opportunity to try that a few years back, when i "dinscovered" solar pannels :) These modules will work onsite, under full weather, in a windowed box. So, i think that to maintain the average energy in the batteries, itll be ok. These is going to be a prototype test, though. Thus ill make any necessary changes later in time, if needed. Antonio Sergio Sena {Quote hidden}> I didn't know what your application was, I just knew that rated output is > usually in full sunlit conditions. > If you were planning on using panels indoors, you'd be sorely disappointed > with their output. > > I'd buy whatever you can from the surplus market and make a 'charge > controller' do the battery charging/maintenance for you. > > FWIW, I ran 8 Siemens 55W panels through a Trace C40 charge controller to > 880AH 12V golf cart battery array to an > Exeltech XP1200 inverter for a few years. > > Dave > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.