Looking for a simple circuit for power regulation and led indicator light

Power intake will be from solar and testing it yesterday showed power fluctuations from 5 volts dc .85 amps to 3.5 volts .4 amps. due to clouds or more important its a non tracking system. The charging circuit I am using uses a chip that is only good until 5.5 volts. Can someone suggest or post a simple circuit that limits voltage (with little waste) to 5.5 volts maximum and controls two leds (one red and one green) - the green led will stay lit if the voltage stays above 3 to 3.5 volts and switches red if the voltage drops below 3 or 3.5 volts (haven't decided on a ceiling or floor voltage). Thanks!! Looking for a low voltage circuit option as the solar panels and charging unit will basically be powering the circuit.

 

Thanks. I just ordered a cheap buck convertor from ebay. I guess what I am looking for now is a simple circuit that turns on a green led for input voltages lets say above 9 volts and if the source voltage drops below 9 volts the green led switches off and a red led switches on... any ideas?

 

Actually yes. My original plan was to run buck/boost convertors directly from teg units run in series but after calculating loss from a small charging unit I figure now that I will run the units in series, reduce the voltage since I have more to work with and use the buck convertor to run the charging chip for super caps.

Any thought on the led lights? Thanks again!

 

I found this circuit. How would I change it so that green led was on for voltages above 12 volts, red for voltages under 9, and nothing for voltages inbetween? Thanks! Oh, also how would I calculate the resistor values in case I need to modify it? What does VR1 do?

http://electroschematics.com/5397/three-state-voltage-indicator/

 

I know but it is sort of necessary for my project..