During many late nights, Adams would stare at the map and ask himself, "What if that substation went down - how would I compensate?" And what if a particular transformer blew? And on and on. "About 3 a.m. you start to get a little squirrely," he says with a smile. These days, engineers keep a treadmill in the room as a late-night diversion.
Managing a power grid is a supreme balancing act. It's a bit like controlling a small wave pool with hundreds of wave machines around its edge. If all the machines are operating at about the same level, there's a basic equilibrium in the water.
But if some machines are churning faster or harder than others, rogue waves can form - and start swamping the entire system. The wilder the waves, the more power plants start disconnecting themselves from the system - to avoid damaging their equipment. But that only complicates the problem. Some wave-making power is needed to tame big waves and bring the pool back into equilibrium.
Last Thursday, as Adams was sitting in his office, the nearby power grids started to be swamped. To stabilize themselves, they apparently tried to suck power in from outside sources, including Vermont.
To switch metaphors, it's as if the other systems became black holes, pulling all available energy toward them. Since electricity travels at virtually the speed of light, no human could have reacted quickly enough. But Vermont's sensors instantly rebelled, walling off the state.
The sensors' action was a godsend. But it also left no outside power flowing into the state. That sent voltage levels - a key measurement of the system's stability - falling fast. Like an airplane losing speed, Vermont's grid risked stalling and crashing. Now the humans had to stabilize things.
Adams and the other engineers knew they had to get in quick contact with Vermont's other utilities. Fortunately, the control room has several "bat phones," including a red instant hotline to the Vermont Electric Power Company, which runs the state's big transmission lines.