solar bike

[John in CR]

OK - I hate to throw some inspiration at ya - First after reading the messages I agree that it aint easy BUT - I disagree that a bike is the most efficient means of transportation - I think that would be Ice Skates

A sail boat is far more efficient than a bike. I routinely travel hundreds of miles on 0 gal/hr (so that would be 200/0 = infinity miles per gallon )

So we could either freeze all bike paths or we could dig them out and replace them with canals.

Sailboats are horribly inefficient for a given energy input. The friction of water is great, and sails are quite inefficient.

Skates are out too, because the human body only runs at about 30% efficiency.

 

[KTP]

OK - I hate to throw some inspiration at ya - First after reading the messages I agree that it aint easy BUT - I disagree that a bike is the most efficient means of transportation - I think that would be Ice Skates

A sail boat is far more efficient than a bike. I routinely travel hundreds of miles on 0 gal/hr (so that would be 200/0 = infinity miles per gallon )

So we could either freeze all bike paths or we could dig them out and replace them with canals.

Sailboats are horribly inefficient for a given energy input. The friction of water is great, and sails are quite inefficient.

Skates are out too, because the human body only runs at about 30% efficiency.

Evidently you have not seen some of the recent advances in sailboats. The BMW Oracle doesn't seem to have a problem with the friction of water, and it's wing type sail is pretty efficient.

" BOR90 is very light for her size being constructed almost entirely out of carbon fiber and epoxy resin, and exhibits very high performance being able to sail at 2.0 to 2.5 times the true wind speed (though some rumors have claimed 4× TWS).[5] She can apparently sail at 20 degrees off the apparent wind.[6] The boat sails so fast downwind that the apparent wind she generates is only 5-6 degrees different to that when she is racing upwind; that is, the boat is always sailing upwind with respect to the apparent wind...
The wing is more efficient than a traditional soft-sail rig setup. On November 10, BMW reported that they hit 32 miles per hour (28 kn) boat speed in a 10 knot reported wind speed" (from http://en.wikipedia.org/wiki/BMW_Oracle_Racing_90)

 

[John in CR]

I'm quite familiar with wing sails. I've even come up with a design for a reefable wingsail with a camber that is variable and the camber can be switched from one side to the other for best efficiency in any direction of travel. I want to include a small removable pair of wingsails on my big cat for wind assist, but for simplicity will probably just opt for a pair of large windsurfer sails that are just somewhere between traditional sails and wingsails.

We're just arguing semantics regarding the definition of efficiency, and I'm really only talking about practical transportation. All the forms using renewable energy are great, so we're firmly on the same side. I'm not real keen on some of the alternatives that burn anything other than hydrogen, but they're better than what we got, and all the different types will probably be required to get the world through this transitional period, but electrics will rule in the end until something yet to be discovered comes along, or atomic power can be made small and safe enough to be in the hands of the public..

John

 

[sk8norcal]

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