February 2006 Market Clearing in the Energy Industry 51 © Copyright 2006, CCRO. All rights reserved. ISO/ RTO/ Pool Credit topic CAISO ERCOT MISO ISO-NE NYISO PJM SPP Generic Trans- mission Owner WSPP Credit Limit Criteria Unlimited credit if short-term ratings are A-1/P1 or better for GMC and Market activity. Unlimited credit if long-term rating are A-2 A- / P2 A3 or better for Market activity All others post collateral. No internal scoring model No maximum credit limit or concentrati on level Threshold Matrix, limited by rating Equity or TNW42 and or internal score. $125,000, 000 maximum credit line Threshold Matrix maximum limited by credit score factor times ($50,000,0 00 maximum credit line for any one participant ) Threshold Matrix maximum limited by rating, TNW and or internal score. 20% credit exposure concentrati on maximum Threshold Matrix maximum limited by rating, TNW and or internal score. 20% credit exposure concentrati on maximum Threshold Matrix maximum limited by rating, TNW and or internal score. $100,000, 000 maximum credit line for any one participant Threshold Matrix maximum limited by rating, TNW and or internal score $25,000,0 00 maximum credit line Bilateral model Bilateral model 42 Tangible Net Worth