How many kWh does 300 of gas use?

To convert gas usage to kilowatt-hours (kWh), you need to know the energy content of the gas. On average, natural gas has an energy content of about 1,000 British thermal units (BTUs) per therm. Since 1 therm is approximately equal to 29.3 kWh, 300 therms of gas would equate to about 8,790 kWh (300 therms x 29.3 kWh/therm).