There are solar charge controllers commercially available that do an excellent job of regulating the output of the solar modules. They are in effect regulators with some additional, nice to have, functions already incorporated. The less expensive versions use pulse width modulation (PWM) to regulate voltage while the more efficient versions use a maximum power point tracking (MPPT) which should ensure that you collect all the electrons available. As Colin indicated, "you cant get something for nothing". You start with a solar module that provides only 8 amp and expect to get 10 amps constantly out of it, not gonna happen. The simple answer here is add another solar module and then you have the potential of 16 amps which can be regulated to 10 amps. The PWM controllers can be had for less than $100, while the MPPT can run as high as $850. The MPPT tend to be designed to handle 10 to 14 modules while the PWM can be had in sizes from 1 module up to 6. These are not hard and fast rules as there is so much variation in size of solar modules. Schnieder, Outback and Midnite Solar all make the MPPT controllers. For a PWM controller I would suggest Morningstar. Even the best controller wont give you a constant amperage because at some point the sun....................sets.
