Human-Powered Everything
 

http://www.thehumanpoweredhome.com/w...readle_saw.JPG

This past Wednesday (EARTHDAY, 2009) I was at the University in Whitewater, Wisconsin.

After attending the keynote speech on Electric Vehicles, I headed out to the parking lot to show off my Electro-Metro, along with Insight, Prius, and NEV owners.

One of the break-out sessions on the program that caught my eye, but I could not attend, as I was busy at the car show, was about human power.

The speaker would be talking about using human power to run household appliances, creating electricity, and more.

One of the people later in the day looking at my car was a woman carrying a large box of books. On the side, it said "Human Power".

Sure enough, she was the author speaking at the breakout session. I didn't have enough money on me right then to buy a book right off her, but I did get to page through a copy. It looked really good.

I just browsed through the web site for the book. I thought it was very interesting. You might too.

The Human Powered Home - Choosing Muscles Over Motors

Cool!

I love human power :) But one must take care in understanding human efficiency.... For you efficiency aficionados, a human in a cycling situation is at most ~25% efficient - that's an extremely fit, trained human... That's before mechanical losses :(

Human power for the developed market, I feel is most suitable in local transport and potentially niche market applications. That is, a human powered home appliances could be costly from a power stand point. Arguably, you would be more fit, but quality of life would likely suffer (I hate stationary cycling, for example - I really enjoy moving through my world :p).

Human Power in emerging markets - especially where in areas without a reliable (if any) source of electrical power are amazing. I strongly support enablers. Money isn't really an enabler (ask a sub Saharan country in turmoil) when compared to tools that can power devices like machinery, pumps, small electrical generators, medical devices etc. etc. I saw a human powered rice thresher at Stanford's extreme affordability presentation day - that's exactly the sort of thing I'm thinking of :)

So that went a bit off topic, but that's me :p

bennelson -

Sounds like a corollary-solution to self-ecomodding?

For a given household gizmo, I'd like to see a breakdown of how much pedaling I'd need to do. For instance, to make some toast, how much pedaling at what effort?

CarloSW2

Wow, that's great. I once used a human-powered lathe :)

Do you have a KillaWatt? If not, next time I make toast I'll measure how much power is consumed ;)

50-75Watts is a fairly sustainable (human fatigue wise) pace on a bike.... But, you're very inefficient at that particular moment as toast is typically a breakfast item, indicating you probably don't have much in the way of readily accessible energy. So you're even less efficient as your body needs to take more steps to convert chemical energy stores into usable energy :p

(better add a second slice :p)

trebuchet03 -

I have a KillaWatt. In the never-ending quest to explore the frontiers of scientific knowledge, I just toasted an English Muffin using a DeLonghi "Alfredo" toaster oven. It consumed 0.09 KWH. The muffin was delicious.

CarloSW2

Yeah, I'm not saying that human power is the most efficient thing out there. But wherever you go, there you are, so human power is great for camping, remote locations, rural areas without grid power etc.

Also, if you are just "wasting" energy, such as riding an exercise bike at the gym, why not generate energy while you are at it.

I also believe that doing something yourself makes you appreciate things much more. If you have ever ran a light bulb off an exercise bike, you know what it takes to power, and are more likely to turn off the lights when you leave a room.

Ever hand-crank your own ice-cream? It's the best tasting ice-cream EVER because of the work you put into it.

One of the exerpts of the book on the web page was an essay on forced human power, including the old treadmills in England they used to make prisons run. It was interesting.

At the other extreme, there are quite a number of electric appliances that actually do a worse job than their human-powered replacements: can-openers and pencil sharpeners, for instance. Or electric guitars :-)

We posed this question in Aircraft design class, would making every passenger on a 737 contribute some pedal power make the jet more efficient.

turns out we would have to carry even more weight to carry water to keep everyone hydrated... this lowers efficiency :(

the human power didn't even make up for the added weight of water/food

You need to apply a bit of creative thinking. The passengers exhale water into the air, no? And it's really cold outside at cruising altitude, so you pass the cabin air through an external condenser, which dehumidifies the air & recycles drinking water...

Now as for food, given that on average a sizeable fraction of the passengers could stand to lose some weight, extra feeding's not really needed. Indeed, you need to factor in the increased aircraft efficiency because of the passengers' weight loss during the flight :-)

The thing about the human body. . .virtually all of your calories go into heating you. It takes 4 BTUs just to heat my body 1 degree. Measuring how much heat you bleed off times 1 btu for every degree pound mass tells you how many degrees.

In that sense if you ever want to lose weight the fastest way is A. consume slightly less or B. wear less because its much easier to let your body heat itself than to try and work off the stored energy.

So if you are trying to lose weight human powered is awesome, or if power is not available, but if it is available and you can't stand to lose any weight its not adviseable(food is way more expensive than gas even if you are just eating straight rice).

Not really that much difference, if you buy in bulk. My local el Cheapo supermarket has about 20 kinds of flour in bulk (I didn't even know there WERE that many kinds, until I started shopping there), with the less-expensive kinds going for around 30-50 cents/lb. Sugar & rice run about the same. Figure 6 lbs of food has the energy of 1 gallon of gas, that's around $2-$3 per gallon-equivalent, so in a comparable cost range.

except for the small factor that 90% of your calories are consumed as heat production. So the human bodies idle would be equivalent to like 3500 rpm. . .

Exertion Instruments
Those are some interesting self-powered electrical instruments. I wonder if they can be improved with TI's hybrid amplifier technology...