The sun doesn’t always shine when we need power the most. Solar panels can only generate electricity when the sun is out, leaving us vulnerable to blackouts and brownouts during peak demand periods or at night. This is where battery energy storage systems come in. By storing excess solar energy for later use, batteries can help bridge the gap between solar energy supply and electricity demand.

What are Battery Energy Storage Systems?

A battery energy storage system is essentially a large battery that can store electrical energy generated from solar panels or the electric grid. The system charges when solar production exceeds electricity demand or when wholesale electricity prices are low. It then discharges stored energy to the grid when demand is high or solar production drops off, like on cloudy days or overnight.

Battery energy storage systems use lithium-ion battery technology, like the batteries found in electric vehicles. But they are scaled up to warehouse size with advanced battery management software to control charging and discharging. Grid-scale systems can store megawatts of electricity to power thousands of homes when fully charged.

Smoothing Solar Energy Production  

One of the biggest benefits of pairing battery storage with solar panels is being able to smooth out the natural variability of solar electricity generation over the course of a day. Solar irradiance levels follow predictable daily and seasonal patterns, peaking at midday in the summer months. But cloud cover and weather events can cause unexpected dips in output. Batteries charge up when the sun is shining brightly and solar production is abundant. The stored energy can then be dispatched during cloudy spells to avoid power interruptions.  

Shifting Solar Power to Peak Times

Solar energy peaks at noon, but electricity demand ramps up in the early evenings as people return home from work. Battery storage systems let solar farm operators store excess daytime solar electricity and then dispatch it during the valuable early evening hours when electricity prices are highest. The batteries effectively shift lower-value midday solar power to higher-value peak demand periods.  

Avoiding Duck Curve Issues 

The mismatch between peak solar production and peak electricity demand has led to the infamous “duck curve” issue in places with high solar market penetration, like California. As more solar floods the grid during the middle of the day, net electricity demand craters, only to spike back up in the evening. This drastic ramping need leaves the grid extremely vulnerable to blackouts if generation can’t come online fast enough. 

By charging up batteries with excess midday solar power and then discharging in the evening, battery storage helps flatten out the duck curve. Grid operators can then avoid turning fossil fuel plants completely off during the day. The steady battery discharge also reduces the steepness and amount of ramping needed in the late afternoon.

Storing Excess Solar Power  

Rapid expansions in big solar farms sometimes generate more power than existing transmission lines can accommodate. Without sufficient grid infrastructure or local demand to absorb it, the excess clean power often has to be curtailed. Battery energy storage allows grid operators to capture that extra solar electricity rather than waste it. The stored power can then be dispatched when needed without overloading transmission lines.

Improving Grid Reliability and Resilience 

Severe weather can knock out transmission lines, causing disruptive power outages. Battery storage systems strengthen grid resilience by providing backup power to smooth over grid disturbances. They can also provide voltage support, frequency regulation, and other ancillary services to stabilize the grid when fluctuations occur. Having batteries distributed across the grid enables quicker responses, too, since the stored power is located close to where it’s needed.  

Combined with on-site solar panels, battery storage creates micro grids capable of operating independently if the main grid goes down. These island able solar storage micro grids can keep providing electricity to homes, hospitals, shelters, and other critical facilities during grid outages caused by storms, cyberattacks, and other events. 

Battery storage unlocks solar energy’s full potential by making it available whenever we need electricity. From smoothing solar variability to shifting solar power for peak demand to improving grid reliability, battery storage offers greater flexibility and value from solar panels. Waaree offers optimized solar storage solutions tailored for home, business, and utility needs. Visit our official website and contact us today to learn more!


This gives you a good overview of how battery energy storage systems help overcome some of the intermittency issues surrounding solar power generation. By charging during times of peak production and discharging to meet peak demand, batteries allow us to capture more value from solar panels. And by stabilizing the grid, they enable much higher clean energy penetration. Battery storage is a pivotal complementary technology that is taking solar energy mainstream. Please let me know if you would like me to modify or expand this blog post draft. I’m happy to refine it further to meet your needs.