Batteries are emerging as a key component in keeping the lights on in the world’s fifth-largest economy.
From humble power banks for everyday gadgets to gigawatt-scale storage systems, a new mindset is transforming how the world thinks about batteries.
Massive energy storage banks have become silent, fast-acting workhorses, appearing wherever scalable energy storage is needed.
Grid operators, utilities, and policymakers worldwide are investing billions, while many others are planning to leverage a cleaner, more flexible power system for millions of electricity users.
A new battery-based ecosystem
With the rise of batteries, a new energy “ecosystem” is taking shape.
And it’s growing rapidly.
Solar generating capacity has surged from 228 GW in 2015—just 1% of global electricity—to 2,919 GW in 2025, accounting for 10% of the world’s energy, surpassing nuclear at 9%. According to an industry report, batteries are helping solve the intermittency challenge of renewable energy.
While wind and solar generate clean electricity, grid-scale batteries store surplus energy to cover supply gaps.
Electric vehicles (EVs) are also playing a role as mobile storage through vehicle-to-grid (V2G) technology, helping stabilize the grid and speed up the transition to renewable energy.
A compelling emerging trend: in regions using a combination of wind, solar, and batteries, power costs have declined, according to the latest industry data.
One example is the Hazelwood Battery Energy Storage System (HBESS), a 150 MW/150 MWh utility-scale lithium-ion battery in Victoria, Australia.
Commissioned in June 2023 at a former coal-fired power station, HBESS stores electricity from solar and wind, enhancing grid stability, easing peak demand pressures, and supporting the state’s shift to clean energy.
And this trend isn’t limited to Australia.
California has just set a major new record for battery storage on the grid, highlighting a path forward for the energy transition.
On March 29, 2026, California’s power grid, operated by CAISO, reached a remarkable milestone: battery storage supplied 12.3 GW of electricity at 7 PM PDT, meeting 42.8% of the state’s total electricity demand at that moment.
This wasn’t just a brief spike—batteries provided more than 20% of the grid’s total supply for nearly four hours (from 5:50 PM to 9:35 PM), helping smooth the evening “ramp” when solar generation drops but electricity use remains high for cooking, EV charging, lighting, and air conditioning.
What the data shows (sourced from GridStatus.io):
- Batteries (purple): 12.29 GW → 42.8% of demand
- Natural gas (blue): 5.97 GW → 20.8%
- Large hydro (dark teal): 3.93 GW → 13.7%
- Wind (green): 2.45 GW → 8.5%
- Nuclear (light green): 2.27 GW → 7.9%
- Other sources (geothermal, solar after sunset, biomass, etc.): ~6%
While solar dominates midday generation, after sunset the grid requires resources that can respond instantly—where batteries now play a critical role.
Batteries delivered—and at record scale.
By evening, solar (yellow) had dropped to nearly zero, highlighting precisely why batteries are so essential for keeping the grid stable.
How we got here so fast
Utilities and developers have rapidly deployed large-scale lithium-ion battery systems—like Tesla Megapacks and Australia’s Hazelwood BESS—that charge during abundant, low-cost solar and wind production and discharge electricity when demand peaks.
Today, over 90% of California’s battery storage capacity has been installed in just the past five years.
This isn’t gradual infrastructure improvement—it’s a rapid expansion fueled by the state’s ambitious renewable targets and the infamous “duck curve” problem, where midday solar oversupply is followed by a sharp evening demand spike.
The surge in utility-scale batteries is also enabled by economies of scale already proven in transportation electrification, driven in large part by a 99% drop in battery costs over the last 30 years.
Putting 12.3 GW in perspective
A solution that was nearly non-existent a decade ago is now available at scale:
- Roughly the output of 15–20 large combined-cycle natural gas plants running at full capacity.
- Equivalent to the generation of six Hoover Dams.
- More electricity than the all-time peak demand of entire countries like Portugal or Greece.
In other words, a technology that barely existed at scale just ten years ago now functions like a fleet of power plants—without burning fuel or emitting carbon during operation.
Why this matters
Batteries are addressing one of the biggest criticisms of solar and wind power: intermittency.
Batteries don’t produce electricity themselves—they store it when it’s plentiful (sunny afternoons) and release it when demand peaks (evenings and busy hours).
This milestone shows they’re no longer a niche experiment—they’re becoming a central part of keeping the lights on in the world’s fifth-largest economy.
California still relies on natural gas, hydro, nuclear, and imports to cover remaining gaps, but this isn’t an isolated event. It’s the latest in a growing series of battery records being set worldwide.
