5V solar power supply to power USb fridge

 Hi there,

I've seen a number of projects where a group of small PV cells are
connected together to allow charging of 5V USB devices. I would
like to build a 5V solar USB power supply, with the intention being
to run a 5V USB can fridge to keep some diabetes meds cool on the
road while my girl and I bicycle around the UK in a few months time.

I'm waiting for a reply from the fridge manufacturer, to see just
how much the USB fridge consumes (I suspect it drains more than the
"official" max of 500mA for a USB device). Once they let me know I
can figure out how many PV cells I'll need to provide

Has anyone on this group managed to create such a power supply, or
have any advice to give me? I'm a solar noob... :-)

--
Kind regards,

Chris Wilkinson, Brisbane, Australia.
"Maybe politicians should ask the people whether
or not they wanted all these wars"...

 

I am an Expert of Power Supply(.....heehee......pls allow me to show off
heehe.......), do you need help?  Beware of the Cold weather, it can take
away your charged power.

Usually USB host supplied power for external device, I have no clue on
your system, please post a diagram so I can help you better.

Jack.

 

Do not use 7805 regulator, it drains too much power from 12V solar power,
I recommend using a Register and a Zener diode instead, if you provide
the load, I can compute the resistance for you to go with a 5.2V Zener
diode.

Jack.

 

Sorry misspelt, Resistor (Register=wrong).

 

Are you kidding me? A shunt regulator is even more wastefull than a
7805.  Better idea is to get one of the switchmode regulators from
Dallas, Linear, or Micropower.