Flexible Combined Cycle

Combined Cycle Gas Turbine Based Thermal Energy Storage


Over the last decade, there has been a dramatic change in the power production paradigm. The energy generated by centralized power plants has been progressively integrated with, and even replaced by, power generation from variable renewable sources. This change presents a new challenge for owners of combined cycle plants which are accustomed to baseload operation with regular maintenance intervals.


Today, Combined Cycle Gas Turbine (CCGT) plants require to operate in a flexible manner: they follow a double peak demand curve, resulting in increased number of ramp ups and daytime stops, as opposed to the traditional method of continuous operation, with stoppages mainly on weekends. As a result, these CCGT plants are experiencing up to 250 start/stops per year, much more than the 50 start/stops per year they were typically designed for as baseload plants.


In light of the foregoing, it has become vital for conventional power plants to change their operation mode and technical performance in order to increase their flexibility, yet at the same time ensure the reliability. The improved flexibility level offered to the ancillary service market is the main way to guarantee the competitiveness of thermal power plants. Reduction of the minimum load, increase of the maximum power, reduction of the shutdown and start-up time, optimization of the ramp-up and ramp-down phases, are all capabilities that are increasingly being demanded and whose value continues to increase.


Energy storage will play a pivotal role in providing the required flexibility and will offer balancing options to these thermal power plants. This is particularly true for Brenmiller Energy’s thermal energy storage solution, which has unique features and can manage the variations in supply and demand at different scales, such as CCGT.


Brenmiller Energy’s thermal storage system, called bGen™, allows CCGT to become more flexible and optimize market participation.


bGen™ allows CCGT power plants to offer better performance in the ancillary service market with respect to power capacity, spinning reserve, frequency regulation, voltage regulation, reactive power compensation and minimization of imbalance penalties.