Well, it might be feasible, but it could be costly for the panel.

I'm going to bed now so don't expect a reply until noon BST.

 

ok thanks for your help. whenever you get back on or if someone else finds this what would it take for one panel to cover everything?

 

Sorry, posted an old IC number from memory. The newer "Simple Switcher" VReg ICs are far more efficient and can boost better than the one I referenced.

Oh, and here's a link to the cells they currently show as in stock:
http://www.goldmine-elec-products.com/products.asp?dept=1174

 

thanks marshalf3. If I used the new IC how would that change the layout of the circuit?

 

You would need to wire it up in the configuration mentioned in the datasheet.

 

ok well I found this datasheet for the simple switcher:http://www.national.com/ds/LM/LM2596.pdf

This is just a guess but I would say Pin 1 goes to V+, pin 2 goes between the resistors and pin 3 goes to both resistors and you leave 4 and 5 out?

Is that even close?

Also I found two different simple switchers, one is 3.3 v and the other is 5 v. Is 5 better in this case?

 

Sorry, that's not correct. This is a switching mode power converter. It uses inductors and diodes to step down voltage very efficiently. I recommend you stick with the LM317T for now as it will be much easier to use. Find a 7V or so solar array rated at 1A to use it with.

 

ok do I want open circuit at 7v or max power at 7?

 

Max power at 7v.

Open circuit means not connected to anything. Once a load is added, that 7v will drop to possibly below 4v.

 

If you hit up their website they've got that built in program you can type some numbers in and it recommends a circuit.