Selfsufficientish.com

One of the most difficult things to explain to people is exactly what a renewable energy system can produce - it gets terribly complicated, so I wanted a way to demonstrate what a couple of small solar panels can do.
"Martin's Solar Sound System" was conceived.....
Using easily available secondhand bits and pieces, which have so far cost me £27 (for the sound machine itself - panels, controller and battery are about £200), I now have my first prototype running - it only consumes about 2 amps (at 12v - about 24 watts), and will comfortably run off a couple of 20w solar panels - on a sunny day, the panels will produce sufficient to play it for several hours while the sun is out, and using a battery in circuit means it'll do a few hours in the evenings too! I can't claim disco "weight" to the sound produced, but it's very listenable, and has a respectable amount of bass - I'm no electronics wizard, so reckon this performance could be much improved upon by those able to design/build their own circuits.
It's all very well generating your own power, but using it wisely is just as important - if you ain't using it, you don't need to generate it - hence a challenge to any electro geeks - can you do better? (less power consumption, more listenable sound!)

can't claim to be more efficient, but then again, I do not have to be efficient.

I produce music in my little studio with 8 panels on the roof, and 6 batteries AND a lot of Caribbean sunshine. I actually LOOSE energy if I do not use a certain amount.

Once the batteries are full, my system automatically shuts off the solar panels from the batteries to avoid overcharging. The batteries can be full at around 10:00 in the morning. If I do NOT use any electricity from then on, I will loose quite a lot of daylight hours of producing energy.

(Even if I DO use energy by operating my music production studio before 10:00h, at around 14:00 the batteries will often be full)