Lights Out, Data On: Mapping the Global Divide in Electrification
Using NASA’s Black Marble nighttime lights data, scientists reveal a pixel-by-pixel look at where electricity still doesn’t reach.
Breaking the Ice:
A new study offers one of the most detailed global assessments of electricity access to date—right down to the neighborhood level. The team used NASA’s Black Marble satellite product to produce global maps of electrification at a stunning 1-kilometer resolution. The dataset spans a decade of daily nighttime light observations from 2012 through 2022, allowing scientists to estimate where people have reliable electricity access and, more critically, where they don’t.
Artificial light is a reliable proxy for electricity access, and the Black Marble dataset, which adjusts for moonlight, cloud cover, and atmospheric interference, is currently the most advanced and publicly accessible way to measure it consistently across space and time. The researchers’ goal was to identify “electrification gaps”—areas with built-up infrastructure but persistent darkness—to inform energy planning, global development goals, and climate models.
While electrification is increasing globally, significant spatial gaps remain, especially in sub-Saharan Africa and parts of South and Southeast Asia. The team has released their results as an open-access dataset, designed to support everything from infrastructure planning to climate adaptation strategies.
Quick Melt:
The world is far from achieving equitable, universal electricity access. Current tracking methods often miss the mark. Global surveys from agencies like the World Bank or the International Energy Agency typically report electrification at the national level. These top-down estimates can obscure the local realities: informal settlements with patchy service, off-grid solar systems invisible to surveyors, and fast-changing urban edges where people gain or lose access rapidly.
By contrast, this study captures trends with a neighborhood-level precision that national statistics can’t match. Using a 30-day moving window, the researchers determined whether a pixel consistently showed signs of light (and therefore electricity) at night. If at least 20% of nights showed detectable radiance above a validated threshold, the pixel was considered electrified.
The implications are far-reaching. First, the model identifies where access is lacking—and thus where the most urgent infrastructure investments are needed. Second, it can detect when and where electrification occurs, a critical input for forecasting electricity demand. And third, because the model uses standardized data over time, it can flag how resilient electrification is—whether it holds steady or flickers during conflict, climate shocks, or economic downturns.
The team also explored mismatches between satellite-derived electrification rates and self-reported survey data. Unsurprisingly, discrepancies were highest in low-resource settings, where illegal connections, low-radiance solar kits, or informal settlements complicate detection. These findings underscore the importance of combining on-the-ground knowledge with remote-sensing tools—and show why policy decisions based solely on survey averages might miss key areas of need.
The Thaw:
How Can This Satellite Data Reflect Climate Change? AccumulationZone Explains.
Climate change is not only increasing energy demand, especially for cooling, but also exacerbating the fragility of existing energy systems. Extreme heat can overload aging grids. Floods and fires knock out transmission lines. Droughts reduce hydropower capacity. And millions still live in regions where no grid exists at all. This is where satellite-based electrification mapping becomes more than just a technical breakthrough—it becomes a tool for climate foresight.
By tracking where electricity is present, stable, or absent, the Black Marble dataset can help governments, NGOs, and researchers identify communities most in need of resilient energy infrastructure. It also enables more accurate modeling of future electricity demand, which is projected to rise sharply as billions of people gain access—and as climate conditions drive the need for fans, air conditioners, and cold storage to protect health and food systems.
Just as crucially, understanding where and how electricity is spreading informs climate mitigation. Electrification is central to decarbonization. Clean cookstoves, electric vehicles, induction stoves, and heat pumps all depend on access to power. But if new electricity demand is met with fossil fuels—as it often is in emerging economies—it could lock in decades of additional emissions. Without localized data on where electrification is occurring, planners risk designing climate policy that misjudges the scale and timing of these emissions.
Moreover, these maps help pinpoint the intersection between development and vulnerability. In areas like West Africa or northern India, electricity demand is rising amid intense heat and rapid population growth. These are the frontlines of both energy transition and climate adaptation. Knowing where the lights are (and aren’t) helps ensure that the solutions—solar mini-grids, resilient infrastructure, climate-smart planning—actually reach the communities that need them most.
Final Thoughts
In a world increasingly dependent on electrification for everything from healthcare to education to climate resilience, understanding the geography of light and dark is more than academic. It’s a roadmap for a more just and sustainable energy future.