[Episode #273] – Solar and Batteries Can Power the World

The Energy Transition Show’s March 2026 interview with Prof. Tom Brown highlights a simple yet powerful model showing that solar photovoltaics paired with modern battery storage can meet roughly 90% of global electricity demand at competitive costs. By focusing on the sun‑belt regions—where about 80% of the world’s population lives—the analysis finds that a full solar‑battery system, including modest fuel‑based backup, can be delivered for under $80 per megawatt‑hour. This price point undercuts new natural‑gas plants and rivals coal and nuclear, reflecting rapid cost declines: solar panel prices have plummeted and long‑duration battery capex now sits around $125/kWh, translating to $65/MWh levelized storage costs.

Brown’s methodology expands on Ember’s earlier work by widening the geographic sample beyond twelve cities and fixing the target coverage at 90% of flat demand. The result is a clearer picture of regional feasibility: equatorial and mid‑latitude zones can achieve high renewable shares with minimal backup, while higher‑latitude areas—such as the UK, Germany, and Canada—face seasonal solar shortfalls. In those regions, complementary resources like offshore wind and hydro can fill the gap, turning the “last 10%” challenge into a multi‑resource solution rather than a barrier. The discussion also touches on the role of storable fuels, primarily natural gas, as a transitional bridge, but emphasizes that continued battery cost reductions could push coverage toward 95‑99% without heavy reliance on fossil backup.

The episode places these technical insights within a broader market context. U.S. renewable generation hit a record 1,162 TWh in 2025, representing 26% of total electricity, and projections show nearly three‑quarters of new capacity will be wind, solar, or storage. Meanwhile, industry giants like Google are deploying the world’s largest battery at Project Skyway, underscoring commercial confidence in large‑scale storage. Together, the data signal that the economics of a solar‑dominant grid are no longer speculative; they are rapidly becoming the baseline for future energy planning worldwide.