Mumbai: The city’s peak power demand once again crossed the 3,400MW-mark on Monday. Sources said peak demand rose to 3,434 MW. It had breached the 3,400 MW-mark earlier on August 18, due to hot and humid weather in the city amid less rains. Power consumption in island city, where BEST supplies electricity to 10.8 lakh consumers and Tata Power to another sizeable section, was close to 800MW on Monday, said sources.