When Thomas Edison built his first electric power stations, there were no electric meters in people's homes. Lacking a better method, he started billing people a monthly fee based on how many light bulbs they had. It wasn't a very precise system.
Restored Westinghouse OB electric meter (circa 1920) by John Lester (CC BY 2.0)
Electric meters (much like the ones we still have today) were soon developed to replace the bulb-counting system. As electricity comes into houses, a little dial turns forward to show how much is used. And while the original designers never considered this possibility, it turns out that the little dial turns backward when electricity leaves a home.
For most people, electricity only flows one way (into the home), but there are exceptions - people who use solar panels, for instance. In those cases, excess electricity created by the solar cells travels back out into the grid to be distributed elsewhere. And in some states, people can can be paid for this excess electricity. The practice is called "net metering" (referring to the total or "net" amount of energy used) and while it started off as a relatively non-controversial practice, there are now big political battles being fought over it.
In this featured episode of Outside/In, Sam Evans-Brown of New Hampshire Public Radio and his colleagues Maureen McMurry and Taylor Quimby explore the origins and evolution of this practice, which all began quite accidentally with a single individual: Steven Strong.
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