IEA reported 108 GW of new battery storage in 2025 (+40% YoY). For Vietnamese homes with high evening load, the key is not only installing PV but improving time-matched self-consumption.
The IEA’s Global Energy Review 2026 states that battery storage is currently the fastest-growing power technology: 108 GW of new capacity was added globally in 2025, up 40% year on year. This matters because energy economics is no longer only about how many kWh are generated, but also when electricity can be used.
For many Vietnamese households, the strongest demand is in the evening. With PV alone, daytime generation does not always align with peak home usage. Therefore, practical bill reduction depends on time-matched self-consumption. PV remains the foundation, while storage can shift part of daytime surplus to evening use and reduce grid purchases during high-use periods.
IEA highlights that installed storage capacity is now eleven times higher than in 2021, around 80% of new 2025 additions were utility-scale, and project durations are gradually extending toward 4+ hours in more cases. For homeowners, this does not mean everyone must install ESS immediately; it means households with high evening load should evaluate PV+ESS with their own consumption profile instead of assuming PV-only is always optimal.
A practical checklist is simple: evening load share, monthly kWh usage, roof suitability, financial objective, and backup-power needs. Decisions should be based on 12-month bill data and real load curves. Source: IEA Battery Storage chapter.
