Washer:
-- 450 watts = 450 joules/second
-- 1 hour = 3600 seconds
-- (450 joules/sec) x (3600 seconds) = 1,620,000 joules of energy for washing
Dryer:
-- 3,000 watts = 3,000 joules/second
-- 1.5 hours = 5400 seconds
-- (3,000 joules/second) x (5400 seconds) = 16,200,000 joules for drying
Addum up:
(1,620,000 joules) + (16,200,000 joules) = 17,820,000 joules
That's 1.78 x 10⁷ joules (C)
The dryer only ran 1.5 times as long as the washer, but it used 91% of the total energy. Why is that ?
The washer only has to run some motors to pump water in and out, shake the agitator back and forth, and spin the tub to spin the water out of the clothes. If you use hot water for the load, it comes from the water heater. The washer doesn't have to heat the water, just pump it in.
The dryer has to run the motor to turn the tumbler, but it also has to make all the heat to blow hot air through the clothes to dry them.
Things that make heat suck up a LOT of energy ... electric furnace, electric stove, clothes dryer, even the toaster, blow dryer, and electric frying pan. They're high-energy appliances.