Figure 10:A two-area system with a proposed transmis- Figure 11:Construction of the line can result in a sion expansion project.System A sees low prices,system greater loss of consumer surplus than the resulting benefit B sees high prices,and a new line seems to make sense. to those consumers who benefit.The greater loss occurs in this case because there are fewer customers that benefit than those that see a price increase.This is not to say that surplus is not improved overall by the addition of the line,but that,in a market-pricing situation,there can be this unintended and important side-effect as viewed from the customers vantage point. System B Flow System B System A Low System A Low 2. LoW入 Low2 Surplus gain for +B consumers 入 入 Surplus loss by 入 A consumers Supply Supply 2016/12/222016/12/22 25