ABSTRACT
This work presents a generic optimization framework (ANNEX model), including three alternative algorithms for the electricity market-clearing process in order to optimally determine the annual energy mix of a power system. The effectiveness of the ANNEX model has been tested on an illustrative case study of the Bulgarian power system to investigate the impacts of each market design on the system’s technical and economic aspects. The results highlight the influences of each market-clearing algorithm on the technology selection in the resulting electricity mix, as well as the effects on the system’s marginal price, capturing both the annual dynamics and the short-term challenges of critical days. The developed methodological framework can provide useful insights on the determination of the optimal electricity mixes, highlighting the system’s requirements to address the future market operating challenges of modern energy markets, subject to several technical, economic, and regulatory constraints.
Nomenclature
Sets | = | |
= | Set of fossil fuel-fired and nuclear power generating units | |
= | Set of demand bids | |
= | Set of dates | |
= | Set of hydroelectric power generating units | |
= | Set of capacity blocks of power units and interconnections (traders) | |
= | Set of external interconnections (imports) of the studied power system | |
= | Set of renewable energy sources | |
= | Set of hourly time periods | |
= | Set of dispatchable power units including fossil fuel-fired, biomass-fired, hydroelectric and nuclear power generating units | |
= | Set of external interconnections (exports) of the studied power system | |
Parameters | = | |
= | Availability factor of each power generating unit | |
= | Available capacity of each power unit | |
= | Available capacity of each external interconnection | |
= | Available capacity of each demand bid | |
= | Available capacity of each external interconnection | |
= | Energy supply cost of each unit | |
= | Energy supply cost of the block order submitted by each unit | |
= | Energy supply cost of each unit | |
= | Energy supply cost of each external interconnection | |
= | Energy supply cost of each unit | |
= | Primary-up reserve supply cost of each power generating unit | |
= | Secondary-down reserve supply cost of each power generating unit | |
= | Secondary-up reserve supply cost of each power generating unit | |
= | Shut-down cost of each power generating unit | |
= | Energy demand bid cost | |
= | Energy exports bid cost to each external interconnection | |
= | Primary-up reserve requirements in each time period | |
= | Secondary-down reserve requirements in each time period | |
= | Secondary-up reserve requirements in each time period | |
= | Tertiary reserve requirements in each time period | |
= | Daily hydroelectric power generation in each date | |
= | Available capacity of each external interconnection | |
= | Installed capacity of each power generating unit | |
= | Available capacity of each external interconnection | |
= | Technical maximum of each power unit | |
= | Technical minimum of each power unit | |
= | Ramp-down limit of each power generating unit | |
= | Ramp-up limit of each power generating unit | |
= | Minimum downtime of each power generating unit | |
= | Minimum uptime of each power generating unit | |
= | Primary-up reserve capability of each power generating unit | |
= | Secondary-down reserve capability of each power generating unit | |
= | Secondary-up reserve capability of each power generating unit | |
= | Tertiary non-spinning reserve capability of each power generating unit | |
= | Tertiary spinning reserve capability of each power generating unit | |
Positive variables | = | |
= | Cleared energy supply of each power generating unit | |
= | Cleared energy supply of each external interconnection | |
= | Cleared energy consumption of each external interconnection | |
= | Cleared primary-up reserve provision of each power generating unit | |
= | Cleared secondary-down reserve provision of each power generating unit | |
= | Cleared secondary-up reserve provision of each power generating unit | |
= | Tertiary non-spinning reserve provision of each power generating unit | |
= | Tertiary spinning reserve provision of each power generating unit | |
= | Cleared acceptance ratio of the submitted block order of each power generating unit | |
= | Cleared energy supply of each power generating unit | |
= | Cleared energy supply of each power generating unit | |
= | Cleared energy supply of each external interconnection | |
= | Cleared energy supply of each power generating unit | |
= | Cleared energy consumption of each demand bid | |
= | Cleared energy consumption of each external interconnection | |
Binary variables | = | |
= | 1, if block order submitted by each power generating unit 0, otherwise | |
= | 1, if each power generating unit 0, otherwise | |
= | 1, if each power generating unit 0, otherwise | |
= | 1, if each power generating unit 0, otherwise |