« Floating / mixed links and updates (5) | Main | Bike powered electricity generators are not sustainable »


Feed You can follow this conversation by subscribing to the comment feed for this post.

Jim Baerg


Regarding the ancient rowers "They didn't have the sliding seat of today's competitive rowers". I recall reading a few years ago (unfortunately I don't recall where) that they might have had something equivalent. Depictions of galley rowers show them with a cushion tied to their buttocks & it is thought the bottom of the cushion was greased to allow it to slide & let the rower use their legs to do most of the work. It might have been a contributing factor to the Greek victory at Salamis.

Jim Baerg


"It is important to realise that pedal powered machines (and bicycles) require fossil fuels."

I don't think that pessimistic statement is justified. (I say pessimistic because in the long run even the most frugal use of fossil fuels will use them up faster than they are created, so if the statement was true there would eventually be no steel for pedals.) However, charcoal from biomass was used to reduce iron ore to metalic iron for millenia, though on a smaller scale than we have been doing with coke made from coal. If necessary we can use the steel in the petroleum fueled vehicles to make a few billion pedal powered machines & since you say they last for a century, the steel production needed to replace 1% of those machines per year would likely be small enough to be done with charcoal from wood.

Also is there any reason iron ore or rust couldn't be reduced to metal using electricity or hydrogen split from water using non-fossil energy? (Aside from coal being cheaper for now.) Steel production would be done near large hydroelectric plants in sparsely populated areas the way aluminum is done now.



I do wonder, if certain hardwoods are strong enough to take up to a certain threshold of human mechanical pedal power, such that you don't need steel or other such things at all in the end?

Ok, it may take plantations, and time, but that could be done sustainably.

Where there's a will, I think there's always a way!

christina brine


I thought you might enjoy this weblink... 507 Mechanical Movements... some of the illustrations are animated. http://507movements.com/



While the axles have to be thicker and the roller bearings far larger there is no reason to think you can not build peddle powered equipment out of hardwood. A carefully knotted rope could work in place of a chain for power transfer without the efficiency loss of belt drives.



If necessary we can use the steel in the petroleum fueled vehicles to make a few billion pedal powered machines

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been saved. Comments are moderated and will not appear until approved by the author. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment

Comments are moderated, and will not appear until the author has approved them.

Your Information

(Name is required. Email address will not be displayed with the comment.)

Let's build our own internet

News & Links


Fruit Walls

  • Fruit walls
  • Urban Farming in the 1600s
    From the 16th to the 20th century, urban farmers grew Mediterranean fruits and vegetables as far north as England and the Netherlands, using only renewable energy.

The Chinese Wheelbarrow

  • Chinese wheelbarrow
  • How to downsize a transport network: the Chinese wheelbarrow
    For being such a seemingly ordinary vehicle, the wheelbarrow has a surprisingly exciting history. This is especially true in the East, where it became a universal means of transportation for both passengers and goods, even over long distances.

Wood Gas Vehicles

  • Wood gas cars 2
  • Firewood in the Fuel Tank: Wood Gas Vehicles
    Wood gas cars are a not-so-elegant but surprisingly efficient and ecological alternative to their petrol (gasoline) cousins, whilst their range is comparable to that of electric cars.

Open Modular Hardware

  • Open modular hardware2
  • How to make everything ourselves: open modular hardware
    Consumer products based on an open modular system can foster rapid innovation, without the drawback of wasting energy and materials. The parts of an obsolete generation of products can be used to design the next generation, or something completely different.

Power from the Tap

  • Water motors
  • Power from the Tap: Water Motors
    Just before the arrival of electricity at the end of the 19th century, miniature water turbines were connected to the tap and could power any machine that is now driven by electricity.

Aerial Ropeways

Other Languages

  • Some articles have been translated into French, German, Spanish, Italian and Dutch. Find them here.