Now Playing: 09-20-13 Marketplace Tech - Should the government push untested energy technology?

Today there are new rules from the Obama Administration on building new coal and gas plants in the U.S. Some of them could require plants to use carbon capturing technologies. Critics say the technology isn't there yet, but environmentalists say the industry is dragging its feet. So how close are we to actually putting less smog into the air -- when we're continuously putting smog into the air?