While forests in Nepal have been shrinking for years, between 2007 and 2010 trees in the South Asian country of 27 million inhabitants began to grow again, reported Al Jazeera English.
Biogas has been credited with the shift, as roughly 250,000 Nepalese now use the fuel.
Biogas is created by combining manure and other organic waste, including toilet waste, with water, which is put underground in an airtight container where it creates methane, which travels by underground pipes into kitchens to be used to cook.
One woman explains how she no longer has to spend hours each day collecting firewood. "We had to steal the firewood from the national park, and the army guards would chase us," she said.
The technology has also allowed Nepal to collect carbon credits, which it has sold to generate $2 million so far.
Watch the video, via Al Jazeera English, below.