We compare the total resource cost and willingness to pay accounting m
ethods of calculating demand-side management benefits and costs. After
a review of Massachusetts Electric Company's process evaluation data,
we conclude that the total resource cost method more accurately repre
sents actual program results. However, even the total resource cost me
thod may be incomplete, since it fails to account for savings associat
ed with efficient equipment purchased independent of the utility progr
am, but as a direct result of participants' positive, educational expe
riences in the program.