In 2007, Congress passed the Energy Independence and Security Act, which mandated higher energy efficiency standards in the US. The law included new standards for light bulbs that were written to spur the lighting industry out of the incandescent age and towards new technologies like LEDs that use significantly less energy.

It worked. As manufacturers adapted to the incoming standards, hardware store lighting aisles began to fill with new LED options, and consumers started buying them in order to reap the energy savings. The national energy use attributable to lighting plummeted -- in 2018, both the residential and commercial sectors used less than half as much energy to power their lights as they did in 2001.

But last month, the Department of Energy under President Donald Trump reined those standards in by limiting the types of light bulbs to which they can apply. Those revised exemptions, which kick in Oct. 7, will protect the sale of certain kinds of incandescent light bulbs that might otherwise have come off the market in the coming months due to poor energy efficiency.

"This action will ensure that the choice of how to light homes and businesses is left to the American people, not the federal government," said a DOE spokesperson in a statement. The move would eliminate a "cost burden on American consumers and businesses."