When it comes to power, Texas is on an island. The state is not connected to either the East or West Coast grids, making it vulnerable in times of crisis. San Antonio Congressman Greg Casar has filed a bill to end that energy isolation. It would require the Electric Reliability Council to finally interconnect. That means Texas could pull in more power in times of need. It could also sell excess electricity. Critics, though, say it would open Texas to federal regulation and oversight.