Additionally, carbon price imposes a higher penalty to the utilities with higher emissions. As shown in Figure , the cost of utilities with direct emissions increases faster than the lowcarbon utilities. This explains why the utility cost at -24% GHG emissions reduction, when the percentage of heating electrification is very low (Table ), grows significantly with the increase of carbon tax (Figure ). By contrast, heating is almost fully substituted by low-carbon electricity at 42% GHG reduction, so the growing carbon tax does not notably change the utility cost.