TTC and RRC Study for the Ethiopia-Kenya-Tanzania (EKT) Transactions

Ethiopian Electric Power (EEP) and Tanzania Electric Supply Company Ltd (TANESCO) have entered into a Power Purchase Agreement (PPA). The PPA provides for a firm long term sale from EEP to TANESCO in two phases. The wheeling transaction will occur through Kenyan power system.

KETRACO (Kenya) is in the process of developing a tariff for the first phase transaction and has determined that it is necessary to undertake a study to develop some transmission related capacities for use in the tariff development process.

The main goal of the study is to evaluate the value of Total Transfer Capacity (TTC) and Reliability Reserved Capacity (RRC) for each of three groups of facilities:

• DC interconnection facilities between Ethiopia (EEP) and Kenya (KENTRACO)
• Internal lines in Kenyan transmission system
• AC interconnection facilities between Kenya (KENTRACO) and Tanzania (TANESCO).

Total Transfer Capacity (TTC), obtained from the network security assessment, is cross checked with calculated PV curves for both, N-0 and N-1 situations.

The Reliability Reserve Capacity (RRC) is determined for each segment of the transmission corridor between Ethiopia and Tanzania, consist of three components:

• RRCA - Deviations of active power flow due to primary response of generators to frequency changes.
• RRCB - Emergency exchanges between control areas and or external systems
• RRCC - Inaccuracies in data collection and measurements.

Type of services provided:

• Load flow analyses
• Network security assessment (n-1)
• TTC/NTC calculation
• Inertial/governor load flow (INLF)
• Voltage stability analyses (PV)