Ready, Aye, Ready

Link: http://www.preservationnation.org/magazine/2008/january-february/cautionary-tale.html

Link is to an interesting article on the difference between sunk energy values versus sunk economic ones when it comes to buildings. One of the major discussions over environmentally-friendly changes is whether or not the net result is better. In any building there is a fundamental value: it's built. A new one would need to be significantly more energy efficient in order to offset the destruction and replacement costs. Yes, there are externalities. If a building is too costly to maintain and labour and material are cheap, it makes economic sense to replace it. If the building is inappropriate to the wanted use, but is in a required location, it makes business sense to replace it.

As always, replace versus reuse is not a simple or easy argument. Take older cars for example: is it better to continue using an inefficient old vehicle versus a new one which has a far superior MPG rating? On the surface and using an economical sunk-cost approach, it's an easy decision: go with the one which uses less fuel. However, that analysis excludes the cost of building the new vehicle and disposing of the old one; all it cares about is whether the new vehicle will be cheaper to operate, mile by mile. If the goal is emissions control, again, the argument seems simple as the older vehicle is less likely to run as clean. Combine occasional use of the old vehicle with alternate methods of transportation (bicycling, public transit for where it's appropriate) and the relative costs change. Does it make sense to replace a vehicle that's appropriate for its periodic use but runs only 2500 miles a year by something that costs a lot to produce but will run those 2500 miles better? What may seem like a minor disparity between the two options for one person may end up being dramatic when spread over thousands. To me this has always been one of the ironies of hybrid vehicles: the vehicles that need the efficiency the least -- the small, already efficient ones -- were those that became the hybrids while the gas guzzling SUVs did not. A car which goes from 32 MPG to 38 MPG definitely saves gas, but wouldn't it make sense to try to get a 12 MPG vehicle to 18 MPG? It may be the same 6 MPG improvement, but the latter vehicle is going to get through the same difference a lot more often.

Nearby where I live there's a house that has been built to strict environmental-usage codes. It's supposedly very energy-efficient. It's also taken three years worth of construction so far and it's not yet complete. Will the vaunted efficiency pay for itself over the lifetime of the house? I remain unconvinced on that one. Would it have been better to upgrade the existing house or would that have been so expensive in terms of labour and material as to be impractical? Did the owner feel the design of the original house was inappropriate to his or her needs? I honestly don't know the answers to those questions even after pondering them for a while.

My instinctive feeling has always been that it's better to repair and reuse than rebuild or replace. Cheap energy has made the latter the more economical option in recent history. It'll be interesting to see whether that continues to hold true.

(Via Kottke)

(WalkItOut Link)