Big Battery Backup to Prevent Blackouts
Solar Power & Energy Storage for Power Grid Protection
Images of a shivering toddler clutching a teddy bear and flashlight come to mind when you think of the electricity crisis that left at least 4.5 million Texans without heat in frigid temperatures for hours to several days back in February 2021. Because record-low temperatures caused an unexpected demand for power that far surpassed what the state had planned for as a worst-case scenario, the power grid failed. To make matters worse, the historic freeze also brought a substantial amount of power production to a screeching halt. Although the Texas blackouts of 2021 were an unparalleled anomaly of circumstances, utility companies across the nation, and the world, are beginning to think twice about power grid protections.
Built during the early 1900s, the power grid in the United States is aging and struggling to meet current demand. Part of the problem is that power plants, whether coal, nuclear, or steam, take a fair amount of time to turn on and run at full capacity. According to the U.S. Energy Information Administration, Annual Electric Generator Inventory, natural gas combined-cycle systems, which account for more capacity than any other generating technology in the United States, take between 1 hour and 12 hours to reach full operations.
Anthony Evelina, an electrical design engineer at CoolSys Energy Design, said, “The way our current power grid is set up can make it difficult to meet fluctuating energy demands.”
Solar energy production is one of the most environmentally friendly ways to supplement the electrical needs of our 332+ million population, but because the sun isn’t always shining, storage is essential. Enter the latest in Battery Energy Storage Systems (BESS).
Battery storage stockpiles excess energy when solar panels are producing electricity and can feed it into the power grid whenever it’s needed, whether the sun is shining or it is the darkest hour of the night. If and when the power grid needs supplemental electricity, these batteries can quickly dispatch their stored energy much faster than power plants can turn on their generators and create power.
Another key point is that BESSs are not limited to working with solar. They can be charged from the grid itself or via any other source of electrical power. This theoretically means that any excess generation, whether it’s from steam turbines, wind turbines, or generators, can be stored rather than wasted.
“It’s a very flexible resource to have when needed,” Evelina said.
CoolSys Energy Design developed the electrical infrastructure and distribution design on an over 350,000 square foot solar photovoltaic and BESS project owned and operated by Convergent Energy + Power for Choptank Electric Cooperative, a Maryland utility.
Convergent has over a decade of expertise developing energy storage and solar-plus-storage solutions and for the utility and business sectors. The company is committed to accelerating the clean energy transition. Electrical engineers from CoolSys Energy Design worked with their team to connect all the components.
The concept is always the same, take power from the solar field and direct it onto the electric grid or into the battery storage system, but there are different inverters, arrays of panels, wiring, power lines, meters, charge-controllers, and transmission lines. All of this technology is relatively new in this application and there are few standards governing the market as of yet.
“Our job is to bring all those building blocks together. We need to make sure that all the specific pieces fit and actually work together with the rest of the grid,” Evelina explained.
Completed in 2022, the energy storage system consists of 19 rows of solar panels. Each row has an inverter and a mini-inverter to convert the direct current (DC) power into usable alternating current (AC) power. Because batteries can only hold DC power, part of CoolSys Energy Design’s responsibility was to design the infrastructure to take the excess AC power, change it back to DC, and store it in those local batteries. The goal of this storage system in Maryland is to provide green energy, help the power grid be more resilient, and hopefully lower electricity prices for local consumers.
Overall, the aging infrastructure of our power grid is already struggling to meet current demands and needs major updating to face the growing population that is increasingly leaning toward electric vehicles and homes.
PV systems paired with BESSs are one way to help make the overall energy system more fluid and reliable. They collect excess power that would otherwise go to waste and store it in a way that can be delivered when needed at a moment’s notice with a lower carbon footprint and overall greenhouse gas emission level than traditional power plants. This means that utilities will have battery power available and not need to kick on their reserve generators as often. It also gives the utility more lead time for when they need to start running additional generators, which means more reliable power for everyone.
Because the cost of big batteries has dropped significantly in the past decade and the latest technologies now allow them to store larger amounts of energy than ever, grid-scale energy storage systems are now seeing record growth. Experts say that widespread energy storage is key to expanding the reach of renewables and speeding the transition to a carbon-free power grid. CoolSys Energy Design is proud to be on the ground floor of this major transition.