Shutting down all the nuclear reactors caused a fourth problem by putting a financial squeeze on power companies. Thermal power stations filled the hole left by the shutdown of nuclear plants, which had accounted for some 30 percent of the electric power mix. As a result, thermal power production approached 90 percent of the power supply, costs for fossil fuels rose sharply, and electric power companies posted tremendous losses. That led to rate increases and consumer complaints not only about nuclear power plants, but also about the monopolistic structure of the electric power industry itself. In the meantime, nuclear power was largely replaced by fossil power, mainly gas powered Plants and oil-powered plants. The shift has had a dramatic impact on greenhouse gas emissions, which rose 4 percent in 2012 and 1.3 percent in 2013, raising Japan’s emissions 10.6 percent above the 1990 rate