Pedal power generation

After disappointing results with my first foray into solar power, I started researching alternative ways of generating power. I was wondering what was on the market in the form of pedal powered generators. I was hoping to find a decent dynamo for a normal bike, or roller type system where a normal bike could be mounted, but looking around so far i’ve only found DIY solutions for the roller systems (modified “turbo trainers”) and very low power dynamo systems. Some of these will charge a mobile phone or other USB device, but I haven’t found anything advertising laptop or 12 volt battery charging.

I did come across these two standalone solutions:-

They both have a 7ah battery, which wouldn’t power a laptop for more than an hour or so, but also both take a full day or more of pedalling to fully charge! If I had had better results with the solar panel, I might have impulse bought one of these to try, but I can’t see them being much use for anything other than emergency/ novelty use.

As ever, i’d love to be proved wrong on this, so any suppliers who want to send me samples to try out, please get in touch!