President Biden wants to spend tens of billions of dollars on transmission lines to transport renewable electricity across states, which he says will improve grid reliability. His climate model of California is showing the limits and risks of this strategy. California’s Independent System Operator (Caiso) on Friday and Saturday issued emergency alerts urging residents to conserve power during the evenings to avoid rolling blackouts. A wildfire in Oregon threatened transmission lines that import thousands of megawatts of hydropower that are needed when the sun starts to go down. Progressives blamed Texas’s power outage in February on its limited ability to...