Battery capacity growth to shift 34% of solar energy to non-sunny hours

According to a report by the energy think tank Ember, increasing battery capacity is playing a critical role in shifting solar energy production to non-sunny hours. Global new battery capacity is expected to reach 459 gigawatt-hours this year, representing a 50 percent increase over the 307 gigawatt-hours added in 2025.

Ember estimates that new batteries installed this year could theoretically shift up to 34 percent of daily solar energy production to evening hours. This marks a significant rise from 18 percent in 2025 and 4 percent in 2021. However, the report notes that 34 percent is a theoretical upper limit, as not all systems are currently optimized or used exclusively for solar shifting.

The report highlights that solar energy's share of global electricity production reached a record high of over 10 percent in the first half of the year. As solar production is projected to grow from 769 terawatt-hours in early 2023 to 1564 terawatt-hours by early 2026, the need for storage becomes more vital to meet demand during nighttime hours when direct solar production drops to near zero.