How About 16 Horsepower?


| 11/4/2011 3:44:23 PM


Tags: self sufficiency, Living on daily incoming solar energy, converting sun to steam to electricity, Vetter Fuel Economy Challenge, Craig Vetter,

12 title 

Living Better on Less Energy  

Western civilization is totally dependent upon cheap and abundant energy. Three quarters of the petroleum we burn in our engines is imported. Could it be cut off suddenly? Without cheap and abundant energy, our way of life would collapse. 

If we value our freedom and independence, we should not be relying on foreign petroleum. We should be making our own energy. 

First… how much power do we need?  

There seems to be something special about 16 horsepower. 

FRANK LEE
12/30/2011 11:04:18 AM

T Brandt is completely right re: unrelenting demand. I fear that any efficiency breakthroughs will be taken as a sign by egomaniacal breeders that the newly "freed up" resources are a green light to go go gonads. Jack: everything I've seen indicates more heavily loaded engines are more efficient- loads on the order of 75-80% of rated continuous output is where peak brake specific fuel consumption occurs (as in, best fuel efficiency, not worst). Look at examples where engines really are run in a steady state (not automotive- too much transient loadings): ships, aircraft, tractors, etc. I think you will find none of them being operated at the low loads and rpms you describe.


Craig Vetter
12/25/2011 2:38:36 PM

I am sorry that my browser Firefox - does not see comments. Gotta use Safari. It has been a month since you posted this. You and I have met and discussed things person to person. All I hope to do in life is: "Get the Big pieces right" Whether it is actual horsepower, peak horsepower, KWh, torque or who knows what, we are homing in what we really need to live better. It is a lot less that most people have been told, isn't it?Merry Christmas


JACK MCCORNACK
11/29/2011 2:18:40 AM

Interesting observations, Craig. I'm with you re the adequacy of a 16 hp vehicle (I think you and I both cruise on about 8 horsepower) but when discussing an engine's horsepower we need to differentiate between peak horsepower available and horsepower actually used. ICEs typically run most efficiently at 1/4 to 1/3 of peak horsepower (at 1/3 to 1/2 of peak horsepower RPM) and if you want a full day's work out of a horse you need to run it at around 1/10 of peak horsepower...but fortunately a horse peaks out at 5 to 10 horsepower so Watt's calculations work pretty well. Point is, replacing a given hp engine with actual horses (or vice versa) depends on how much steady state hp you need and how long you need to use it. Horses burn fuel very efficiently (and burn biofuel at that) but you have to let horses idle 24 hours a day, even on days you don't need horsepower. If you stop an engine it stops consuming fuel. If you stop a horse, well, it stops consuming fuel too, but you can't get it started again.





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