Base model (no fixed effects) is the authors' primary specification; the alternative model with plant-size dummies is an explicit robustness check. The abstract/text headline long-run own-price electricity elasticity is ~ -1.90 (base model -2.002). || 'The long-run own-price elasticity of electricity demand is estimated at about -1.90, thus indicating that a 1 % increase in the price of electricity implies a long-run reduction in electricity demand of almost 2 %.' (p.484); 'In our base model estimation, we include no fixed effects... as a robustness check we also estimate an alternative model specification' (p.483)
Henriksson, E., P. Soderholm, and L. Warell (2014): "Industrial Electricity Demand and Energy Efficiency Policy: The Case of the Swedish Mining Industry." Energy Efficiency 7(3), 477-491