Lake Tahoe residents could be in the dark Sunday. NV Energy and Liberty Utilities may shut off electricity Sunday to prevent a wildfire. As many as 50,000 NV Energy customers could be affected-some are in communities that had to evacuate due to the Caldor Fire. The 219,000-acre wildfire is 71% contained at last check. The fire’s progress has slowed in recent days, but a Fire Weather Watch in effect this weekend with high winds could hamper progress.