I live alone in a house. I want to know which is more energy efficient

(1) Switch on hot water in the evening and do all laundry, bathing, cleaning, then switch heater off

(2) Leave hot water on all the time.

I asked this question at work and it almost started WWIII.

(I posted this in the Household Tips section, too.)

Hi there Faber,

if you keep the heater switched on throughout, you are ofcourse avoiding the large amount of (fuel/power)energy needed to ignite the heating system;

however,
supposing your entire consumption of the hot water is , say of two and a half hours, then
I am of the opinion that you are saving Energy.
Look at the daily 20+hour consumption you are being saved from
along with the energy losses apart from the Thermal Energy.

Pin~Jinx / anarchist

Yes, 'tis better to shut it off at night, and turn it on again the next. And especially if you're going on vacation for a few days. You save a lot of energy by not having the heater losses during the day that repeatedly requires the unit to be turned on. However, it certainly would be inconvenient to not have hot water when you wanted it or if you needed it, so it would require perhaps a lifestyle adjustment.

Thanks, both answers sound logical to me. I wouldn't need to adjust much. I leave at 7:00 A.M. and return about 6:00 p.m.
Weekends is different.