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Sweden didn't become an eco-superstar overnight. In 1991, the country implemented a tax on CO₂ emissions, sulfur emissions, and most non-biofuel energy production, so it's often costlier to hurt the environment in Sweden than it is to help it. The government has also been waging a cultural campaign, as Anna-Carin Gripwall, director of communications for the Swedish Waste Management's recycling association, told The Independent. "Swedish people are quite keen on being out in nature and they are aware of what we need do on nature and environmental issues. We worked on communications for a long time to make people aware not to throw things outdoors so that we can recycle and reuse."

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In 2014, Sweden imported 2.34 million tons of trash from foreign countries, who paid Sweden about 400 kronor per ton, or about $45 U.S. per ton, to take it off their hands. That's 800 million kronor, or roughly $90 million U.S., going straight into Sweden's coffers. But that's not where the story ends. 85 to 90 percent of that waste goes into incineration plants, which in turn produce heat that's distributed directly into district heating systems. The system doesn't even require the plants to transform the energy into anything else—the heat goes directly into people's homes, although the plant can also produce electricity. That's yet another revenue stream: consumers pay for the electricity and heat. It's a win-win.

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Sweden's system has its detractors. Burning trash contributes to CO₂ emissions, the argument goes, and it would be better to invest resources into properly sorting and recycling the waste instead of incinerating most of it. But according to Business Insider Nordic, the emissions created from burning other countries' garbage is actually much less than would be created if those countries dealt with their own waste. That's how efficient the Swedish system is. As a result, it's showing no signs of slowing down: Since 2005, Sweden's waste imports have quadrupled.

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