The Green New Deal that Democrats unveiled last week has a grand ambition to eliminate fossil fuels in 10 years, retrofit every building in America, and guarantee high-paying jobs in the bargain. If you want to see how that works in the real world, consider the public housing projects near Rep. Alexandria Ocasio-Cortez’s New York office.

The New York City Housing Authority (Nycha) has a more modest goal of a 30% reduction in greenhouse-gas emissions by 2027. As part of its plan, Nycha is switching to LED lighting, which lasts longer than incandescent bulbs and consumes less energy. Sounds smart, until you see how many union workers it takes to screw in a light bulb.

One recent project focused on 23 housing developments, and changing the light bulbs and fixtures there cost $33.2 million. Supplies account for a fraction of that cost. Under Nycha’s Project Labor Agreement, electricians make $81 in base pay and $54 in fringe per hour, and overtime is usually time and a half. Add administrative and contracting expenses. All in, Nycha paid an average of $1,973 per apartment to install LEDs.

For Ms. Ocasio-Cortez, sky-high labor costs are part of the plan. Her Green New Deal resolution would create “high-quality union jobs that pay prevailing wages” and reinforce “the right of all workers to organize, unionize, and collectively bargain.” It also mandates upgrades for “all existing buildings in the United States” to “achieve maximal energy efficiency.” In this worker’s paradise, there’s a $1,973 LED in every socket.