“Benjamin Franklin was really lucky his kite wasn’t struck by lightning,” says James Kirtley, MIT professor of electrical engineering and a specialist in electric machinery and power systems. The average lightning strike contains about 1 million joules, enough energy to fry the founding father in his boots. “The typical house in the U.S. has 100 amp service or about 28 horsepower,” says Kirtley. Unfortunately, relying on lightning bolts to power our hair dryers, TVs, and refrigerators would be far from cost effective. The problem is that the energy in lightning is contained in a very short period of time, only a few microseconds. Further, to obtain that 1 million joules, one would have to handle a voltage of several million volts.
Absorbing lightning and converting it to useful energy would be an extraordinary challenge, Kirtley explains. It would require complex capture and storage facilities and distribution systems that in the end would unlikely yield enough energy to justify their expense. To start with, attracting a lightning bolt would take much more sophisticated equipment than an iron key at the end of a silk string. Tall metallic rods extending high above the ground would do the trick, drawing any electrical charges in the atmosphere and directing them into a facility. But robust and dependable safety mechanisms would also need to be built to immediately contain the huge burst of energy and prevent the entire facility from being blown to bits.