battery.mom · The state of the energy transition
Where battery power stands.
Solar and wind became the cheapest electricity humanity has ever built. The question stopped being whether we can generate clean power — and became whether we can store it. This is where that race stands today.
For a century, electricity meant burning something — coal, gas, oil. The last decade quietly broke that rule.
What follows is the story in numbers: how clean generation overtook the growth of fossil power, why batteries became the keystone of the whole system, and how fast they are now being built. Every figure here comes from public IEA, IRENA, and BloombergNEF data — sourced at the bottom.
01 — Generation
The grid tipped toward clean power.
In 2015, the world's solar farms generated 245 TWh of electricity. In 2025 they generated 2,653 — a 10.8× rise in a decade. Wind more than tripled. Add nuclear, and 42.5% of the planet's electricity is now low-carbon.
The line that matters most: in 2025, the growth in clean generation outpaced the growth in fossil generation for the first time — coal and oil output actually fell.
Source: IEA Global Energy Review 2026.
“A solar panel is useless at night. A turbine is useless when the air is still. Batteries are what turn an intermittent supply into power you can count on — and until recently, we barely had any.”
Source: IEA Global Energy Review 2026.
02 — Storage
Then storage went vertical.
Cheap clean power created a new problem: it arrives when the weather cooperates, not when you flip a switch. The fix is storage — and the build-out just went exponential. Annual utility-scale battery additions climbed from 3.8 GW in 2020 to 86.8 GW in 2025, a 23× jump.
In 2025 alone the world added 107.7 GW of battery power and 247 GWh of capacity — 90% of it lithium iron phosphate (LFP), the cheaper, longer-lived chemistry that finally made grid storage pencil out.
03 — Geography
One country is building most of it.
The boom is not evenly shared. China alone added 55.1 GW of utility-scale storage in 2025 — about 63% of the global total — pairing it with the world's largest solar build-out. The United States is a distant second.
The technology is global. The deployment, for now, is concentrated — which is exactly why where your region stands is worth watching closely.
Source: IEA Global Energy Review 2026.
04 — The snapshot
Where the energy transition stands, end of 2025.
05 — The road ahead
The backbone is still being built.
BloombergNEF projects cumulative grid storage will reach 7,300 GWh by 2035 — roughly 8× today's 885. If that holds, the 2020s will be remembered as the decade batteries stopped being an accessory to the grid and became part of its backbone.
And this is only the first act. The harder questions come next — how fast it should scale, who it leaves behind, and what comes after lithium. That's where this story goes from here.
Source: BloombergNEF 2H 2025 Energy Storage Outlook; historical via IEA.
Sources & method
battery.mom takes no ads, no sponsors, and no affiliate money. Every figure on this page is traceable to a public source:
- IEA Global Energy Review 2026 - battery storage — Power-capacity additions by year and region; 2025 values based on Benchmark data.
- IEA Global Energy Review 2026 - electricity supply — Global generation by source, regional electricity mix, and 2025 generation changes.
- IEA Global Energy Review 2026 - solar PV and wind — Renewable capacity additions and selected market solar/wind additions.
- IRENA Renewable Capacity Statistics 2026 press release — Global renewable capacity expansion and share of total power expansion.
- IEA Global EV Outlook 2026 — Global electric car sales exceeded 20 million in 2025 (a quarter of new cars); China supplied about 60% of global sales.
- IEA Global EV Outlook 2025 — Historical sales milestones: ~3M (2020), 6.6M (2021), >10M (2022), ~14M (2023), 17M+ (2024); China ~11M in 2024.
- BloombergNEF 2024 Lithium-Ion Battery Price Survey — Volume-weighted average pack price of $115/kWh in 2024; average EV packs reached $97/kWh.
- BloombergNEF 2025 Lithium-Ion Battery Price Survey — Latest survey: volume-weighted average pack price fell to a record $108/kWh in 2025.
- BloombergNEF 2H 2025 Energy Storage Market Outlook — Long-run cumulative energy storage projection of 2 TW / 7.3 TWh by 2035.
- Carbon Brief summary of Ember Global Electricity Review 2026 — Public GWh storage-addition context and battery capacity relative to daily solar generation.
Part of The Long Sunrise — the whole argument, from the first fire →
Now explore the numbers yourself.
The story above runs on the same open data behind every tool on battery.mom.