“…Utility planning studies also vary in their treatment of off-system sales or purchases for energy or capacity. Some utilities included the option to buy or sell power from neighboring utilities or third party generators explicitly or indirectly within the CEM and/or PCM (Seattle City Light 2012;Avista 2011;Portland General Electric 2009;Idaho Power 2011, Xcel Energy 2011; Arizona Public Service 2012), while others did not include such market interactions in order to ensure that their system would not rely on other parties' investments (PNM 2011;Tri-State Generation & Transmission 2010). 9 Some others do not report the method used to determine future price levels for purchased or sold power (e.g., LADWP 2011).…”