California is incredible, but making it livable, what with its droughts, floods, fault-lines and wildfires, has never been cheap.

Climate change only adds to the cost, as anyone paying spiraling utility bills there knows. Those same bills will thwart California’s green, progressive aspirations. Making them digestible means going back to the basics of what a bill pays for.

Meredith Fowlie, a professor at University of California, Berkeley, just published an important cost-benefit analysis of PG&E Corp.’s massive project to bury 16,000 kilometers (10,000 miles) of power lines in Northern California. You may recall the utility went bankrupt in 2019, swamped by liabilities arising from several deadly wildfires attributed to its overhead wires. The wildfires aren’t letting up and PG&E’s undergrounding project has contributed to a roughly $380, or 16.5%, increase in average bills this year. Fowlie finds diminishing returns for each incremental mile of wire buried, in the form of rising implied costs per avoided ignition, suggesting other strategies may be more cost effective.