# Utilizing Energy Storage for Operational Adequacy of Wind-Integrated Bulk Power Systems
## 5 Conclusions  
Operational planning of electric power systems is routinely carried out to ensure the availability of adequate resources. Growing uncertainties brought about by rapidly growing penetration of intermittent renewable generation is causing challenges to operation planning. ESS are being introduced to mitigate the adverse impacts of variability and uncertainty in power generation. The advent of these new resources in power systems requires new approaches and methods to evaluate operational adequacy in operational planning. This paper proposed a new framework for operational adequacy evaluation and illustrated its application on a test system.  
The presented study showed that the operational adequacy risks are substantially increased when a conventional generating unit is replaced by wind resources. The presented example showed that the operational adequacy measured in LOLP is increased by over a factor of 6 when a 20 MW conventional unit is replaced by 80 MW of wind power in the test system. The paper also demonstrated how a  
Figure 12: Alternative operational adequacy planning of wind and ESS integrated power system.  
benchmark criterion selected based on past acceptable performance can be used to determine the need to take preparatory actions to ensure acceptable performance during system operation. The example study showed that the utilization of ESS can reduce the LOLP below 10% of the specified criterion. The evaluation results obtained from the studies quantitatively show that the system operational adequacy risk varies substantially with different operating strategies that are dictated by the ownership of the ESS and the market objectives. Among the two operating strategies illustrated in the presented study, the grid-supported ESS operation resulted in an operational adequacy risk that was about 5 times lower than the wind-coordinated strategy without grid support. The paper illustrated how comparative analyses of different operating strategies of ESS facilities can be conducted to derive a solution to maintain acceptable operational adequacy. The paper illustrated examples of two remedial measures in the form of incorporating different percentages of expected wind generation capacity in the unit commitment process and utilizing additional resources like mobile ESS to mitigate the operational adequacy risk to an acceptable level. It should be noted that these studies were carried out in advance at a certain planning horizon, and therefore, provide opportunities to make alternate resource management plans and take preventive actions before the actual operation. Thus, the proposed operational adequacy assessment framework is expected to assist system operators and policymakers to plan and facilitate the operation of system resources, including renewables and ESS facilities, to operate within acceptable risks.  
[PERSON] developed the methodology, analytic tool and performed the evaluations; [PERSON] supervised the research work. All authors have read and agreed to the published version of the manuscript.  
This research was jointly funded by the University of Saskatchewan and the Natural Science and Engineering Research Council of Canada under the Energy Storage Technology Network Grant.  
The authors declare no conflict of interest.