Battery energy storage (BESS)

How BESS works

Battery energy storage systems consist of many individual cells linked together to form modules, racks, and finally a full‑scale plant. When excess electricity—often from solar panels—flows into the system, a chemical reaction stores that energy inside the cells. When the grid needs power, the reaction runs in reverse and the stored electricity is discharged back to the network.

Why BESS matters

• Grid stability – Batteries can respond in milliseconds, smoothing out sudden spikes or drops in generation.
• Renewable integration – They store surplus solar energy produced during the day and make it available at night or on cloudy days.
• Peak‑shaving – By delivering power during high‑price periods, BESS reduces the need for expensive peaker plants.
• Backup power – Critical facilities (hospitals, data centers) can rely on batteries when the grid fails.

Typical size example

A residential BESS might be rated at 10 kW/13.5 kWh, enough to run essential appliances for several hours after sunset. Utility‑scale installations are measured in megawatts (MW) and megawatt‑hours (MWh); for instance, a 50 MW/200 MWh plant can supply the average daily electricity use of about 30,000 homes.

BESS and solar power in Israel

Israel’s sunny climate leads to rapid solar growth, but the country also faces steep evening demand peaks. By the end of 2023, roughly 1 GW of battery capacity had been commissioned, most of it paired with solar farms in the Negev and the central district. These hybrid sites store midday solar output and discharge it after dark, reducing reliance on imported natural‑gas generators and helping the grid meet the national target of 30 % renewable electricity by 2030.

Bottom line: BESS turns intermittent solar energy into a reliable, dispatchable resource, making clean power usable whenever it’s needed.