Despite successes in reducing poverty globally in the last two decades, almost one billion people are still living without access to reliable and affordable electricity, which in turn negatively affects health and welfare, and impedes sustainable development.

Researchers have been using satellite images of Earth at night to study human activity for almost 30 years and it is well established that these images – commonly referred to as night-time radiance – can help map issues like economic growth, poverty, and inequality, especially in places where data are lacking.

In developing countries, areas that are unlit at night generally indicate limited development, while brightly lit areas indicate more developed areas like capital cities where infrastructure is abundant.

An obvious example can be seen in satellite imagery of both North and South Korea where the South is brightly lit up along the whole stretch of the country while the North has only small amounts...