The sun after sunset: storage unlocks solar's potential
Solar PV has become the leader in global renewable capacity growth, thanks to fast deployment, modularity (from rooftops to utility-scale), and cost declines. In 2025 alone, the world added 510 GW of solar PV, representing almost three quarters of all renewable power additions. [+]
However, solar generation is time-dependent, as output is concentrated during daylight hours, while electricity demand in many power systems often rises later in the day. This increasingly drives curtailment, price volatility, and the need for flexibility. [+] This is why storage becomes a complimentary technology to solar. Short-duration batteries can shift solar generation into evening peak hours and provide fast grid services. At larger scale, storage helps grids integrate higher shares of variable renewables more securely. [+] Battery storage is one of the fastest-growing clean energy technologies in the power sector and plays a key role across utility-scale projects, households, businesses, and decentralized electricity systems. [+]
Geopolitical instability and the growth in electricity demand are reshaping the role of renewables. In the past, the energy transition has been driven primarily by emission targets and falling technology costs but following the geopolitical events and cost-of-living crisis, affordability and security are also becoming key priorities. [+] In this context, solar PV and wind can strengthen energy independence by using domestic resources, limiting exposure to fuel price volatility and to external supply shocks. Additionally, global electricity demand is expected to grow by more than 3.5% per year on average to 2030, increasingly influenced by data centers and AI power needs. [+] This also increases the strategic importance of enabling technologies, including storage and grid optimization tools. [+] [+] [+]
Key Facts
- Solar’s role in power generation keeps expanding1
It is becoming a mainstream power source thanks to low costs and scalability. But its daylight profile increases the need for storage and flexibility. - Battery economics are improving quickly2
Storage options are evolving quickly. Amongst the storage technologies currently available, short duration batteries dominate the market. Storage costs are experiencing the greatest improvement among transition supporting technologies. - Solar + storage is a good combination3
Combined systems are turning “cost effective solar” to “cost effective reliable energy on demand” combining solar with storage. - Capital is moving toward solar and storage4
Electrification and the need for low carbon energy sources coupled with energy security risks due to geopolitical instability boost investments in these technologies, that are also part of a suitable solution for data centers + AI increasing power demand. - Solar + storage still face challenges
Solar + storage growth depends not only on technology costs, but also on grid capacity5, policy stability6, battery regulation7, critical mineral supply chains8, and biodiversity impacts9. - Real projects show solar becoming evening power
Solar + storage projects are already being deployed across different geographies and use cases, with examples including agrivoltaics in Colorado10, project Nexus11 in California; Gannawarra12 and Lakeland Solar & Storage13 in Australia; and the Trujillo, Extremadura hybrid solar-plus-storage Spain14.
1. IEA [+], 2. BloombergNEF [+], 3. BloombergNEF [+], 4. IEA [+], 5. IEA [+], 6. IRS [+], 7. European Parliament [+], 8. IEA [+], 9. WWF [+], 10. Jack´s solar garden [+], 11. ESS [+],12. ARENA [+], 13. MPower [+],14. Zelestra [+]
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