Water has a specific heat capacity of about 4.2 Kilojoules per kilogram per degree Kelvin, so it would take about 6 Kilowatt Hours of electricity to heat 100 Litres of water from 15 degrees centigrade to 65 degrees centigrade. As a standard immersion heater is 3KW, so it would take 2 hours to heat 100 Litres of water.
Drinking a large amount of carbonated drinks at bedtime can also cause hiccups, as the air in these drinks can distend the stomach. Consuming a large amount of alcohol before going to bed is another possible cause of hiccups during sleep. The excessive amount of alcohol can cause the stomach to distend.
Some causes of hiccups include: 1  Eating too quickly and swallowing air along with foods. 2  Eating too much (fatty or spicy foods, in particular) or drinking too much (carbonated beverages or alcohol) can distend the stomach and irritate the diaphragm, which can cause hiccups.