A small miracle: Yesterday Georgia Power announced that the second new nuclear unit at Plant Vogtle entered commercial service, “the first new commercial reactors built from scratch in the U.S. in more than three decades.”

With the second unit now online, known as Unit 4, the two reactors combined will produce enough electricity to power 1 million homes, without adding heat-trapping carbon pollution to the atmosphere. The first new unit, Unit 3, has been in service since last July, joining the original two Vogtle reactors, which have been producing electricity since the late 1980s.

The addition of the two new units makes Plant Vogtle the country’s largest generator of carbon-free electricity, Georgia Power says.

However, the news is not all good; as the Wall Street Journal reports, “adding two new reactors cost more than $30 billion, more than twice the initial estimates, and are a major reason no other large nuclear-power facilities are under development in the U.S. and the industry focus has shifted to smaller designs.”

Over the past two decades, the U.S. has done a lot more proposing and then canceling plans to build nuclear plants than building them, despite the desire for energy sources that do not involve fossil fuels. “South Carolina Electric & Gas Co. and state-owned utility Santee Cooper spent more than $9 billion before abandoning construction on the reactors at the V.C. Summer Nuclear Station” in 2017.

Late last year, “NuScale Power Corp., the first company with US approval for a small nuclear reactor design, canceled plans to build a power plant for a Utah provider as costs surge.”