Pedal-Electric: Power from the People

The (admittedly awesome) ability to power your whole home with a pedal-powered generator isn’t feasible…yet. But with a surge of interest related to climate change, and recent investments in battery and energy recapture technologies, we’re entering an exciting phase in the advancement of pedal electric transportation, more commonly known as human-powered vehicles (HPVs). 

For those of us who are newer to this converging point between high-performance, sustainable engineering, and carbon-neutrality, here’s a little primer on how pedal-electric power came to be, and why it matters.

Pedal Power – An Oldie But Goodie

Like many smart, simple ideas, the idea of generating power through human-assisted rotary motion has been around for a long time. Low Tech Magazine’s Kris De Decker provides a comprehensive overview of pedal electric innovations, which really hit their stride late in the 19th century. 

Yes, folks around the globe were harnessing the benefits of rotary motion long before pedal power had its first true moment in the spotlight. But the introduction of chains and sprockets of different sizes allowed a much greater mechanical advantage than pedals and cranks alone could provide. 

This greater mechanical advantage, in turn, introduced pedal power to a more diverse array of applications, including lathes and saws, tool sharpeners, and drilling machines (including at least one dental drill in the late 19th century, though the lack of any further attempts in dentistry is, perhaps, telling).

Pictured: Yikes…

While the variety of applications for pedal power was important, so was its net-positive impact on the toll of human-powered labor.

In the Low Tech piece, De Decker notes:

“The historical importance of pedal powered machines can be easily overlooked by people who grew accustomed to fossil fuels and ubiquitous electricity. Therefore, it cannot be stressed enough how much of an improvement pedal power was in the light of thousands of years of human drudgery. Pedals and cranks make use of human power in a near-optimum way.”

But despite chains and sprockets (in addition to our legs) helping us realize a near-optimum way to power small machines, pedal power’s next obvious application would hit a significant snag.

Home of the Future?

As stated in our intro, the idea of powering an entire home by pedaling is, well, appealing (ESPECIALLY if you have kids). And, at roughly the same time pedal power was enjoying its surge in popularity, the Edison Electric Illumination company was changing the way families looked to power their homes. While progress was slow, by 1925 roughly half of American homes were powered by electricity.

So, why didn’t powering homes by pedal naturally come along for the ride?

Because pedal power gets more complicated when electricity enters the equation. Despite all the technological leaps and bounds we’ve made since some poor someone visited the world’s first and last pedal-powered dentist, generating electrical energy is far less efficient than generating mechanical energy, pedal-powered or not.

Not available for comment. (Source: Dentalcorp.com)

At a basic level (one at which I am forced to operate daily, forgive me), pedaling a bike to create energy is no different than spinning the giant turbine generators that provided 47.7 percent of power in the United States in 2019.

Despite the fact these generators are typically driven by steam due to their sheer size, they’re no better than their human-powered ancestors when it comes to the losses inherent in transforming motion into electricity. For instance, in the typical power plant using coal to produce its steam, only about ⅓ of energy produced actually makes it into the grid.

The rest, according to the laws of thermodynamics, is lost during this transformative process as heat. To be fair, newer/more innovative power plants do a better job of capturing this heat and putting it to use. But the fact remains, transforming mechanical energy into electricity requires you to put a lot more in than what you can get out. Still, power is produced. How much pedaling could we actually need to power a home? 

Again, in 2019, the average American home used an average of 30 kilowatts per day. By comparison, a professional cyclist can produce 400 watts per hour during the average race.

This means that even if we hooked said cyclist up to a generator capable of running at 100% efficiency, they would still need to maintain that 400 watts per hour pace for 75 hours to provide one house with one day’s worth of energy. 

Original source: CyclingUtah.com

Now, hold up gang. While the realities of the math here are more sobering than sitting in the chair at a pedal-powered dentist, they’re no reason to give up on pedal electric power. What if we’re simply looking at this backward? Is pedal electric power far too limited? Or, might we be consuming far too much power?

Sustainable Thinking Is a Two-Way Street

Here’s where we make the tiny turn back to why this is all relevant to the Racer and Kronfeld Motor Company.

Because the little thought experiment above is a good reminder that there are as many ideas of what “home” means as there are people living in them. And if we’re really going to make substantial strides towards truly sustainable living, we need to challenge ourselves to innovate in all directions. 

Pedal-electric power can get better at producing power, and we’re excited to be playing a part in making this so. But buildings (and vehicles) can get better at using less of it. Lasting change is going to take innovation and improvement holistically. There will be no silver bullets. But what’s inspiring here is that more opportunity to make improvements means more room for us all to dive in and help out.

Food for thought.

Till next time folks, let’s keep thinking #netzero.

Ben Schmidt

Author Ben Schmidt

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