Friday, July 14, 2017

Efficiency Meditation

We use that word without often considering its meaning... and most ot the time it leads to no confusion. "Conrad's Prius is sooooo efficient!" will not elicit too many arguments, but will lead to statements about how many miles per gallon he has been getting.

Thirty years ago, I provoked some warm discussion by asserting levelly that my sweetly tuned 36 horesepower 1200cc 1960 Beetle was not nearly as efficient as my friend Scott's 3500 lb. 4 door 1963 Mercury, with its 390 cubic inch V-8 which preferred to guzzle the higher grade swill.

If you can correctly assume that the efficiency implied is 'miles (traveled) per gallon (of fuel consumed)' you will be wehre most advertising copy writers and the general public start out, and seem to stay. But 'fuel efficiency' can also mean 'ton-mile per unit fule consumed.' While I may have enjoyed the argument, I was also able to use Scott's car to make a point that is getting more germane as more and more people become awere of their 'carbon footprint' and want to minimize harm personally, while pressing to realign practices and technologies globally.

Scott's beast, which never managed to exceed 19 miles pre gallon, even on the highway, was getting 2.5 times as much 'stuff' from point A to point B but only consuming 19/32 the fuel of my 1600 lb Beetle in the process. And if you put three big frat brothers in his car, the change in performance and ...'efficiency,' was very hard to detect, while stuffing three passengers into my beloved old Wolfbang meant that one could not hold 62 mph on a 3% incline, mileage per gallon would drop to the mid 20s, and the high gears were seen less frequently.

You all need this concept and this vocabulary to think about our transport needs. The very compelling argument for the MTA transit bus is not the 5 mpg it gets, lumbering around Queens... it is the 20 cars it keeps off the road while doing it.

We need to ponder whether the over-the-road Peterbilt tractor, pulling a trailer with a 10 ton load should not be replaced, wherever practicable, by a 2 engine, 100 car freight train using 1/8 the same diesel, for every payload ton-mile.

the term 'efficiency,' by itself, lacks the specification of 'something-per-unit-of-something else.' Even the seeimgly specific 'fuel efficiency'

No comments: