Southwest Renewable Energy Transmission Conference

May 21, 2010

This report contains transmission planning data that may be conceptual in nature and is subject to change. The transmission projects listed may change scope or not be constructed.

Transmission Ownership Colorado

PSCo System Statistics 20094153 Miles of Transmission251 Substations Served25 Generators Served9 Wind Generators (1258 MW)1 Solar Generator(8 MW PV)PSCo Operating Company Peak Load 6249 MW (Actual) (7/14/2009)PSCo Balancing Authority Peak Load 7457 MW (Actual) (7/14/2009)

Historical Peak Operating Company Load 6927MW (7/212005) Historical Peak Balancing Authority Load 7766MW (7/212005)

Senate Bill 07-100Upon recommendations by the 2006 Transmission Task Force on Reliable Electricity Infrastructure, the 66th General Assembly passed Senate Bill 07-100Under SB 07-100, PSCo must meet the following requirements:Designate Energy Resource Zones (ERZ)Develop plans for the construction or expansion of transmission facilities necessary to deliver electric power consistent with the timing of the development of beneficial energy resources located in or near such zonesConsider how transmission can be provided to encourage local ownership of renewable energy facilitiesSubmit proposed plans, designations, and applications for certificates of public convenience and necessity to the commission for simultaneous review

Senate Bill 100 Project Status*Project status and dates subject to change

New Lamar-Comanche 345 kV & Lamar - Missile Site 345 kV ~ISD 2016-2017New San Luis Valley-Calumet-Comanche 230 & 345 kV lines ~ ISD 2013New Midway-Waterton 345 kV ISD 2011New Pawnee-Daniels Park 345 kV -2nd circuit ~ISD 2016-2017New Missile Site 230 kV (ISD 2010) & 345 kV (ISD 2013)New Ault-Cherokee 230 kV ~ISD 2015-2016New Pawnee-Smoky Hill 345 kV, ISD 2013Current SB-100 Transmission Plan10-22-2009New Lamar Vilas 345 kV ~ISD 2016-2017

High Plains Express Initiative

Two 1,280 mile, 500kV, AC lines through WY, CO, NM and AZ3,500 4,000 MW of transmission capacityConnects Regional Projects11 parties participatingUnder second phase feasibility studies

Completion of HPX InitiativeIncreased local generationInclusion of new renewable generation plantsReduced carbon footprint in the local communityCost of energy favors export of local generationInability to utilize all local generationSell generation on the wholesale market to New Mexico and Arizona

PSCo Public Website and Contact InformationSB-100 web sitehttp://www.sb100transmission.com

High Plains Express web sitehttp://www.highplainsexpress.com