Chile’s energy transition is well underway, with a strong penetration of wind and photovoltaic renewables and a consistent reduction in energy prices.
An increase in photovoltaic and wind penetration of the Chilean hydrothermal system creates new demands for the operation of thermal power plants such as (i) ramps of increase and reduction of generation; and (ii) generation at the lowest technical minimum values to optimize the availability of cheaper renewable energy. In certain cases, as it cannot compensate the variations of solar (and wind) energy with the speed and the quantities required, electrical systems operators are forced to limit the renewable generation according to the dynamic limitations of thermal plants in order to safeguard the continuity of the system’s energy supply. Similarly, some conventional power plants are used to provide ancillary services for frequency and voltage regulation, sometimes over their technical minimum values, occupying an additional fraction of the offer at a higher dispatch cost. Therefore, determining how to include a larger fraction of dispatch from renewable plants in the provision of energy and ancillary services is significant to achieve optimal economic dispatch and the ultimate goal: a 100% renewable mix.
That is why First Solar, Engie Laborelec and the Chilean Electric Coordinator planned and conducted the first test of ancillary services from a photovoltaic power plant in Latin America. The tests carried out were:
- Primary Frequency Control (PFC)
- Secondary Frequency Control (SFC)
- Voltage Control (VC)
- Combination of PFC and SFC
- Combination of PFC and VC