An automobile that runs on air is being touted as "clean." At first when you read the Los Angeles Times article you get the impression that this car is some kind of perpetual motion machine. Then, the power source is revealed: compressed air shoved into high-pressure storage tanks using, what else, an electricity-driven compressor. The air-propelled car may have some advantages. But, using renewable fuel is not one of them. Unless the electricity used comes from a renewable source, owners of such cars will simply be generating pollution and global warming gases from the smokestacks of their local power plants instead from the tailpipes of their cars. The moral of the story? Always trace back "clean" energy devices to their energy source and ask, "Is the actual source of the energy clean and renewable?"
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