Stationary bike that stores power for charging things

I found this recently and thought others might be interested. It is an article about a commercially-available exercise bike that stores the power generated that can then be used to charge things.  Link: https://www.cyclingweekly.com/products/this-exercise-bike-can-store-your-pedalling-power-and-run-your-fridge-is-this-the-future-of-indoor-cycling
[url=https://www.cyclingweekly.com/products/this-exercise-bike-can-store-your-pedalling-power-and-run-your-fridge-is-this-the-future-of-indoor-cycling]cyclingweekly.com[/url]

It's an odd review -- the writer didn't test the actual unit.

I wonder how hard it is to pedal. Turning a generator is hard work, and there's no coasting like on a regular bike. Neat idea though.

Who is the target audience for this bike power station? The price point is much higher than a do-nothing battery, yet its inspiration is war zones. In my opinion: the form, function, and especially price don't really match up. I'd like to see something more than a press release about this system, especially from a cycling magazine... No product test? Really?!?!

I've put some thought into this sort of thing myself, for when I'm granted stewardship of an acre here at Wheaton Labs. Were I to develop something like this, it would be on a recumbent frame (the bikes that "lean back" like a lounge chair) and would include a simple inverter system that takes input from both pedals and solar to charge the battery bank.

It doesn't have to be fancy to work very well. If I tried really hard, I might be able to spend US$3K on my proposed system. And I'd be able to sit on a recumbent for an hour. On a regular bike seat, pedaling hard enough to charge the system? ...I'm doubtful my ass could handle that, literally.

What's that old saying... if it sounds too good to be true, it probably isn't.  I know my husband did some calculations for someone who was wondering how they could protect their freezer during power outages. The answer was, two adults would have to pedal most of their day depending on the weather.

So the article leaves out a lot of details. The unit can *store* "2kW" (note that the writer has misused the units and probably means 2kWh) - no where does it say how long an average human would have to pedal to get the unit fully charged to the 2kWh.

It also says "the bike is capable of generating 50 to 300W/h as you pedal." That's a huge range! At the 50 W rate, it will take 40 hours of continuous pedaling to fully charge the battery.

It doesn't seem to show any form of gearing. I was always told that you bike most efficiently if you choose a gear that doesn't overly tax you. And that can change with time as you get tired. If I was designing something like this, I'd want a really good gearing system. I would have included info like that if I was advertising the unit.

I've also read that if your goal is to use pedal power to accomplish work, rather than trying to get some place, a recumbent style is more efficient for the human body. However, I've *never* seen a bike generator in a recumbent style, ( I have seen it when it was directly powering a machine, rather than a generator.)

So over all, I think the devil is in the details, and many of those aren't sufficiently nailed down to know how practical this would be for anything more than charging phones/tablets/laptops. That said, I've always thought that driving to the gym to use electricity to get exercise seemed a bit counter productive, so having something like this in your home, so you don't waste time and energy on the "driving" part, and actually charging small electronics would be very motivating for me.

Well said, Jay.

Not the greatest review, I agree, and the price is high. I posted it mostly because I found it interesting that such a product would be commercially available. A thing like this was a dream when my kids were little; a closed loop, tv/video game system. As solar pv's have gotten so cheap it is hard to justify, but I am still interested as a way to charge batteries in an off grid situation.

Have you guys seen pedal-power.com?  they have recumbent bikes that can power a bunch of different attachments. Never seen one in person, but find the concept very interesting.

https://pedal-power.com/

Tim

The Japaneses Railways have walking surfaces that generate power from the masses of people that walk on platforms.

[quote=T. Smith]Not the greatest review, I agree, and the price is high. I posted it mostly because I found it interesting that such a product would be commercially available. A thing like this was a dream when my kids were little; a closed loop, tv/video game system. As solar pv's have gotten so cheap it is hard to justify, but I am still interested as a way to charge batteries in an off grid situation.

Have you guys seen pedal-power.com?  they have recumbent bikes that can power a bunch of different attachments. Never seen one in person, but find the concept very interesting.

https://pedal-power.com/

Tim[/quote]
HI Tim,
To give you an idea based on my own research on average you can produce about 150WHr per hour of energy. Athletes more, sedentary people less. If you wanted to build one forget the several thousands model "All"  you need is a an old road bike, a stand, a permanent magnet motor (treadmills are a great source), a fan belt, some diodes, a charge controller and a battery. They do work but as you yourself mentioned not very useful with cheap solar panels available everywhere.
Cheers,  David

T. Smith wrote:Have you guys seen pedal-power.com?  they have recumbent bikes that can power a bunch of different attachments. Never seen one in person, but find the concept very interesting.

https://pedal-power.com/  

Those are some slick looking units and also not inexpensive! They don't have an integral battery either, so you have to pedal as you go.

David Baillie's comment about the cost of solar panels is justified, but are dependent on having sun when you need it and at least one place that installed them, had them stolen  barely a month later. At least bike gizmos can operate in the dark and out of sight!

T., I'm really glad that you posted it - it's good for all of us to consider what's available, and what are the pros and cons. I believe it was Prof. Suzuki who analyzed that for their weight, the bicycle was the most efficient form of transportation ever invented. However, it *was* invented for transportation. Determining/creating other uses is something that's always appealed to me, but I can remember an old exhibit at a Science Center and I was so light, and it fit me so poorly, I had no hope of generating any meaningful amount of electricity. Rather than it making me think - well that's a useless concept that will never happen, it more makes me analyze when I see the concept - could an average (or in my case below average) human use this comfortably and effectively? And if so, would it generate enough power to be worth it?

As John C Daley added, small, unexpected energy sources can add up to a useful amount if designed well and implemented in appropriate locations.

If we add up all the alternatives, we might get somewhere better than where we currently are. When Texas lost power a couple of winters back, having some pedal generators could have been pretty useful - I'd bet there weren't many solar panels producing during the storm! It's all about resilience.