Performance during Evacuation

At low speeds, the Prius travels in electric-only mode - until the battery needs charging. Then the computer turns on the gasoline engine.

Chris,

I think all the present hybrids will run about 1 mile a 30 MPH before they start the engine to recharge the battery. The battery is supposed to be good for about 20 miles but they don't allow it to discharge very much under normal operating conditions. After about a mile, my Ford will run the engine about 30 seconds to recharge the battery. That is the most fuel efficient mode of operation and the Escape will easily get over 40 MPG driving at low speed mostly of battery. The Escape only has AC with the engine running so it would be hot in the slow traffic unless the AC switch is set to the position that forces the engine to run continuously. Of course that mode will cut the gas milage to about 25 MPG. Except for AC part, the hybrid is ideal for the kind of driving you had during the evacuation. Hybrids do best in slow, stop and go driving.

The ICE will come back on to recharge the battery, but also (and more likely in this case) to bring everything - especially the catalytic converter - back up to operating temperature.

Also remember that ALL of the energy in a hybrid vehicle comes from gasoline. The hybrid systems just recover/recycle energy that is usually just lost and reuse it in more efficient ways.