Solar panels offer many advantages over other forms of energy. Burning coal and oil causes air pollution and contributes to global warming, as does their transportation, while nuclear power is not only expensive, but faces strong public opposition following the Chernobyl disaster. Several developing countries, especially Mexico and India, are investing in solar panels, finding that it already makes economic sense to install them in remote villages, thus avoiding the need to build expensive power station and power transmission lines. Nearly two-thirds of all the solar panels made in the US are exported to developing countries.