I’d call myself a ‘fair weather’ mountain biker, and that fair weather season for me is about 7-8 months of the year. It’s always been a challenge keeping up my fitness level in the off season. A few years back my wife bought me a spin bike, which I do ride on occasion, but it’s pretty boring and my mind would get busy wondering “wouldn’t it be cool if I could turn this mundane exercise into something useful?”. That’s where this journey starts.
I’ve always had an interest in alternative energy and have recently had a fascination with human powered energy generation. This latest fascination has driven my quest to build a general purpose spin bike pedal generator that would be efficient and practical to use. The result is a proof of concept that I fondly refer to as “Ugly Genny” or “Ugly Genny Ross” – with Ross being the brand of stationary bike I found on craigslist that became my test platform (I wasn’t quite ready to rip apart the nice spin bike my wife had bought me). Through much trial and error, and several ‘Ah ha’ moments, I’ve come up with a winning combination that will produce useful energy, provides a good workout and will serve as a great resource in the event of a power outage. I have actually used this pedal generator to charge my cell phone exclusively since getting a new phone in early December of 2017. I do this through both direct charging of the phone, and charging portable battery packs and using them to finish charging my phone. It takes a over an hour and a half to fully charge my phone, an iPhone 7 Plus, with a 2 amp charger. I will pedal charge the phone for 30-60 minutes, while simultaneously charging several battery banks (those with Quick Charge or USB C input work best), along with iPads, other family members cell phones and other devices that need some juice. I also tend to get warm while pedaling, so I’ve hooked up a fan to help keep me cool. As of this writing, I have not plugged my phone into a wall outlet to charge it, using only the pedal generator and the battery packs that I have charged to power my phone. If you find this interesting, stick around, join my YouTube channel and learn more about how I built this machine.
2 Replies to “Adventures of building a pedal generator”
Thank you so much for sharing all of this information. I found your site via a Reddit post you made, which sadly got no attention. But, fortunately for me I stumbled on it. It’s archived now, so I couldn’t comment to you on Reddit.
I fully plan to make one of these chargers. I see you have evolved from a hub motor in 2017 to an RC motor on more recent builds. Was that a result of the cost of the hub motor or the performance of the smaller (and cheaper) RC motors? I’ll read your website for the answer!
Hi Eric, glad you found my site!
You’ve hit the nail on the head – I was trying to come up with an easy to build, lower cost solution. Quite honestly, the hub motor version is my ‘go to’ generator that I use all winter long. I’ve found (unscientifically) that the bike trainer and spin bike add-on RC motor versions are not as efficient and powerful as the hub motor version. Happy to help as you plan your build!