Question

coal has about 30E6 J of energy per kg, but a power plant can only use 30% of this energy to make electricity. How many kilograms of coal have to be burned to light a 100 W light bulb for one day​

Answer 1

A standard 500 megawatt coal power plant produces 3.5 billion kWh per year, which is enough energy to power 4 million light bulbs all year. To power most of a household's electrical appliances for a year it would take around 4,750 pounds of coal