Energy myth-busting: Is it cheaper to have heating on all day?

A question about : Energy myth-busting: Is it cheaper to have heating on all day?

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Energy myth-busting: Is it cheaper to have heating on all day?

Best answers:

• This all just seems commonsense. I'm surprised the article was necessary.
• My FIL worked for British Gas as a heating engineer for 42 years and swears blind that it should just be left switched on with a thermostat at the temperature you want. He's a (very) tight northerner so I'd be surprised if this weren't the most cost effective option.
  I've always hated my OH turning the heating way down/off when we go away for weekends, only to come back to a freezing cold house and no hot water. Now that we have a toddler there's no way I'm letting him do that, so ours is on with a thermostat set to 20. Lovely.
• Ye canna change the laws of physics!
  If you want to change water from its liquid state to its gas state in order to get it out of the washing, you will have to use energy. Whether you do that by using a dryer or by making the heating work harder, you will use the same amount of energy. The heating might be cheaper per kWh but its less directed so you may end up heating the whole house for longer rather than a small drum. Vented dryers are wasteful of energy as the heat all goes outside whereas at least with a condensor dryer the heat stays in the house and offsets that from a well controlled heating system.
  Which brings me to the first comment - there is such a thing (widely available) as a programmable thermostat which combines timer and stat - which is better than either option listed. The problem with timers is that if you are going to run the heating flat out on a timer you end up heating the house too hot in order that as it cools when the heating is off, it still stays warm enough. A programmable stat still allows it to be off when you are out (or cooler at night etc) but avoids the wasteful overheating.
• 1. Well firstly please make this thread a sticky as the 'Cheaper all day v timed' question comes up a dozen times each year.
  The normal variation of that question is:
  'Which is cheaper - on 24/7 at, say 15C or in timed bursts to 20C'
  A question nobody can answer!
  2. The EST have a fixation about standby consumption. The manufacturers got to grip with that problem many years ago and standby consumption for, say, TVs is tiny - fractions of a watt. You can leave a modern(up to 10 years old) TV on standby 24/7 for a year and the cost is pence. Even the worst of my TV's - an old 32" CRT has a standby consumption of 0.6 watts. so left on 24/7 it will cost 63p a year with electricity at 12p/kWh.
  Obviously any saving by switching off at wall is welcome, but the emphasis on standby consumption leads many people to think it is the major cause of high electricity bills - and it aint! We get countless posts complaining about high electricity bills and nearly all are at pains to point out that they switch off TV at wall.
  3. This is misleading IMO:
  Quote:
• Physics is not a strong subject on M S E ?
• Q.
  Should I use a tumble dryer, or place washing on an airer with heating on?
  a. An airer is better because tumble dryers use a lot of energy.
  Try timing it so you put your washing out on a clothes horse during the hours your heating comes on. Normally, that way you wouldn't use any more energy.
  To anyone who's property either has, or is close to having, high humidity and/or damp problems, this is without doubt extremely bad advice, and the the last sentence is simply incorrect.
• Oh god, here we go again
  Opened up another can of worms
  Trying to figure out what is cheaper is actually quite difficult. So many things to consider, like the outside temperature, the inside temperature, the starting temperature, whether it's a sunny day, a windy day or a rainy day. Which orientation your house is, what level of insulation you have, drafts, windows. The list is practically endless.
  One thing is for sure, leaving it on all day at a similar temperature to timed is going to use more gas. It might only be Ј15 a month extra, that all depends on running tests in your house and reading the meter.
  The most balanced advice possible which would apply to most people is to have it on timed and put the temperature as low as you feel comfortable.
  Temperature wise, the hall in my house is large and cold, so 16c on the thermostat equals 21c in the living room / sitting room and 19c in the bedrooms. For us thats nice a warm without it feeling to stuffy.
  The advice about drying clothes in doors isn't great, try to time your wash days with sunny days, and the times where this is impossible then tumble dryer it is.
  Also some things do need to be turned off standby. Believe it or not, a microwave consumes more electricity per year maintaining the clock timer than it does in average use.
  You can save a quarter on your TV energy bill by turning down the back lighting on LED / Plasma sets to levels that are still natural and comfortable to watch.
  Half the cost of broadband router use by turning it off overnight when it isn't used. My set top box uses 11watts in standby so that is off overnight. Granted these things are tiny compared to electric heating, kettles, fridges, washing machines, tumble driers and dishwashers. But it's habit now.
• I can't imagine why MSE Guy is perpetuating this stupid myth by starting a 'debate' that has been done to death on here every time the weather turns chilly!
  Might as well start a thread on whether Neil Armstrong really walked on the moon...