1. THE POWER OF POSSIBILITY AESO current limits for Alberta-BC transfers Jeff Palermo – KEMA/AESO

2. THE POWER OF POSSIBILITY Overview Regional planning and operating criteria AESO criteria What limits Alberta-BC exports

3. THE POWER OF POSSIBILITY Planning and operating criteria Criteria balance reliability and cost Criteria include Starting conditions Test to be made (contingency) Conditions defining success system performance Where criteria come from NERC – North America WECC – western states and provinces AESO – Alberta system

4. THE POWER OF POSSIBILITY AESO criteria The system is planned and operated so Under normal conditions (n-0) voltages and loadings are normal [NERC] No singe contingency (n-1) causes loss of load [NERC] All facilities below applicable rating [NERC] Following any single contingency – prepare system for next contingency (n-1-1) [NERC] Within 20 minutes [WECC] Multiple contingencies (n-2) may cause load loss but no cascading [NERC] All facilities below applicable rating [NERC] Even extremely severe contingencies must not cause cascading from one system into another [NERC]

5. THE POWER OF POSSIBILITY Consider Base case TTC OPP 304, Table 4 n-2n-1-2 This is TTC, but ATC will be 0 since 65 MW is needed for TRM To the extent southern generation reduces SOK loading, exports can be increased

6. THE POWER OF POSSIBILITY The limiting facility Benalto – Red Deer 240 kV (900L) Current limit Thermal limit ( MVA ) Component SummerWinter 1,400A584Conductor thermal rating 1,700A705Conductor thermal rating 1,120A466conductor element in substation 1,200A499current transformer & air break switch

7. THE POWER OF POSSIBILITY Reference documents Transmission Reliability Criteria (http://www.aeso.ca/rulesprocedures/8677.html)http://www.aeso.ca/rulesprocedures/8677.html Export Capability ( http://www.aeso.ca/gridoperations/8904.html )

8. THE POWER OF POSSIBILITY ¿¿Questions??