Install modular electrical backup system with capacity for providing 70 amps of emergency power in two 240-volt circuits and six 120-volt circuits. Assume existing propane gas supply. Include generator mounted on 2-by-4-four-foot concrete or composite pad, automatic transfer switch, load center, exterior disconnect, and grounding rod. Include 30 feet of conduit and electrical cable for generator connections; grounded cable for circuits; 5 feet of flexible fuel line for connection to existing rigid gas supply line; and automotive-type storage battery.