As we introduce more renewable generation, such as wind and solar power into our energy mix, the need to invest in energy storage grows. Energy storage helps us maintain a constant flow of power when intermittent resources such as wind and solar are not available.
Storage technology supports local reliability and demand response for our customers and is integrated into our distribution and resource planning processes. For example, batteries are a relatively flexible solution that can be mobilized and relocated to meet changing demand in the system. Today, we are also exploring new ways of combining energy storage with renewable generation to support the grid.
The system provides one of the first energy storage systems in the PJM transmission region to support frequency regulation.
The concept of energy storage is not new, but the need for reliable, cost-effective solutions has never been more critical. We are exploring new ways of using different types of energy storage to manage demand and support a more agile grid. Today, as the energy landscape transitions to more distributed and intermittent energy resources, we need to expand our ability to store energy to maintain grid reliability.
Another type of storage – pumped storage – has been serving customers of Appalachian Power since the mid-1960s. APCo’s Smith Mountain Pumped Storage Project can generate 585 MW of electricity for up to 11 hours or can be used for short periods of time to meet peak energy needs.
Applications of Distributed Energy Storage
- Reliability improvements - AEP has more than a decade of experience with battery storage, which can provide back-up power in case of an outage. During that time we installed three 2-MW NaS (sodium sulfur) batteries in Appalachian Power, Ohio Power and Indiana Michigan Power. Each battery is capable of providing back-up power for more than seven hours when loss of power from the substation occurs.
- Frequency regulation - Batteries have the ability to rapidly respond to balance load and generation in real time on the grid. Regional transmission organizations (RTOs) are recognizing the need for greater amounts of frequency regulation to maintain system stability with the increased integration of variable generation resources.
- Firming of renewables - Wind and solar often do not generate energy when and where it is needed most. Deploying batteries to combine with wind and/or solar energy can allow for better use and management of variable renewable energy sources.
- Peak shaving - Batteries can provide power during peak demand times to meet customer demand while alleviating strain on the power grid.
- Power quality - Batteries are capable of conditioning the flow of power so it can be used to protect sensitive electronic equipment.
New energy storage projects will allow solar power to extend operation past sunset and into evening peak demand periods. We continue to explore new opportunities to leverage the unique aspects of energy storage resources for expanded use in transmission, distribution and wholesale applications. Policymaking on these issues is extremely important to our ability to enable new technology and deploy it on the transmission and distribution grid.