Sewage—refuse liquids or waste matter usually carried off by sewers—is at the front lines of a global movement for clean energy. Innovative U.S. cities are digging into their dirtiest depths to create new sources of power that optimize economic benefits, generate clean energy, and control pollution. This wastewater-to-power movement is just beginning to catch on in China. But with some of the largest and most densely populated cities in the world, the country could be poised to lead a sludge-to-energy revolution.

In the war-torn Jordan River Valley, we can meet the “strategic objective of reducing conflict by promoting cooperation on shared waters,” said former defense official Sherri Goodman at a recent Wilson Center event on environmental peacebuilding. Even in the midst of political disputes, Jordanians, Israelis, and Palestinians must work together to manage the scarce supplies of clean water to protect their health, their economies, and their security.

Russia is “playing politics with energy supplies,” said U.S. Secretary of State Rex Tillerson at a major policy speech at the Wilson Center this week. He accused Russia of wielding natural gas “as a political weapon” and said that ensuring European energy security was “fundamental” to U.S. national security objectives. In Europe, the debate is raging over how best to achieve energy security in the face of the twin challenges of Russian dominance and the need to decarbonize the economy. The ongoing securitization of Russian natural gas could not only complicate the road to a low carbon future in Europe, it could also undermine a European integration project that has mostly been a success.

$1 billion sales in two minutes. More than 250,000 purchases every second. Singles’ Day, China’s annual retailing extravaganza, absolutely crushes Black Friday: E-commerce giant Alibaba raked in $17.8 billion in gross sales during last year’s event, more than double the combined total of $6.8 billion in sales during the United States’ 2016 holiday shopping kick-off. The shopping spree lasts only 24 hours, but its environmental impacts will extend for decades.

Climate change can undermine stability in the Middle East and North Africa, where both the United States and Europe have critical foreign policy and security interests. The Middle East and North Africa (MENA) region “is impacted by climate and resource scarcity risks now, in the medium, and in the long term,” said Nick Mabey, director and chief executive of the environmental think tank E3G, during a recent Wilson Center event on building climate resilience in MENA countries. “It’s a region that is highly vulnerable to climate change,” said Mabey, and “also incredibly vulnerable to global systems.” 

To meet the climate challenge, city leaders are committing to ambitious emissions targets, designing decentralized action plans, and sharing lessons in transnational networks. Since growing cities are a large source of global emissions, their efforts could contribute substantially to global climate objectives. As the world’s climate experts gather next week in Bonn, Germany, for the 23rd Conference of the Parties (COP-23), urban initiatives will be a key focal point of the agenda-setting conversation.

With air pollution causing more than one million deaths in 2015 and reducing the lifespan of citizens in northern China by three years, clean energy has become a top priority for China’s leaders. China tops the world in wind and solar power installations and the government plans to invest more than $360 billion through 2020 on renewable energy. But the green energy transition needs more than renewable power generation: Long-distance electricity transmission could play a key role in cleaning up China’s brown skies. Our recent study estimated that transmitting a hybrid of renewable and coal power through 12 new high-voltage transmission lines could prevent 16,000 deaths from air pollution exposure, and avoid 340 million tons of CO₂ emissions in China.