Marked preferred as the paper's ONLY reported own-price estimate (per-paper rule), with caveat: the authors disavow it as a demand response. || "Finally, the insignificance of the price coefficient may be explained by two related factors. ... as big price movements have not taken place in the observed period ..., the price variable is not a determinant of electricity demand." (p. 1030)
Dulleck, U., & Kaufmann, S. (2004): 'Do customer information programs reduce household electricity demand? The Irish program.' Energy Policy, 32, 1025-1032.