Immersion heater costs.

[mrsmelly]

Hi Peeps

 

Now I am not anal about running costs as life is too short to continualy monitor such things BUT I was just having a shower and wondered............................I am at present one of the poor unfortunates stuck in a marina. There is however ONE benefit to marina dwelling that being a leccy plug in and leccy at 8.32 pence per unit. I have my immersion on 24/7 365 to ensure always loads of hot water. My question is ( I am bored ) what setting should I have the immersion on? for instance I have it on its hottest setting I think its a 5 now when wasing up showering etc I have to add cold water so as not to be far too hot so am I better to say have immersion at number 3 and need no or less cold water? does it work like that or what? At present the boss and myself have unlimited water for our use and even if having too long hot showers directly after each other the water is still red hot, we have a hot and cold fill washing machine also so what do yas think?

 

Thanks

 

Tim

[Guest]

Hi Peeps

 

Now I am not anal about running costs as life is too short to continualy monitor such things BUT I was just having a shower and wondered............................I am at present one of the poor unfortunates stuck in a marina. There is however ONE benefit to marina dwelling that being a leccy plug in and leccy at 8.32 pence per unit. I have my immersion on 24/7 365 to ensure always loads of hot water. My question is ( I am bored ) what setting should I have the immersion on? for instance I have it on its hottest setting I think its a 5 now when wasing up showering etc I have to add cold water so as not to be far too hot so am I better to say have immersion at number 3 and need no or less cold water? does it work like that or what? At present the boss and myself have unlimited water for our use and even if having too long hot showers directly after each other the water is still red hot, we have a hot and cold fill washing machine also so what do yas think?

 

Thanks

 

Tim

 

If you are heating water to a temperature higher than required then you are wasting money. If you turn the stat down to a lower setting the element will be on less and hence you will use less leccy, and the water will not need cold adding to it to get to an acceptable usable temperature.

[Dave_P]

You'll save money by reducing the setting on the immersion becasue you're heating water to cool it back down. The hotter you set the immersion the more energy is used. Also raising the water temp from 60 degrees to 70 degrees uses more energy than raising the temperature from 50 degrees to 60 degrees because it's higher above the ambient temperature. if you have a tiny calorifier, you may need to heat to high temperature and mix in cold in order to have enough hot water for a shower, but it doesn't sound like you're in that category.

[by'eck]

If you have it on 24/7, a lower thermostat setting (say 60°C or less) will give you water that doesn't scold whilst wasting less heat through whatever calorifier insulation you have. Less likely to leak through PRV as well.

[nicknorman]

The issue is the loss of heat from the system whilst the hot water is being stored. Heat lost is directly proportional to the temperature difference between ambient around the calorifier, and the hot water inside. Therefore storing water at a cooler temperature will waste less heat.

 

However in context, the amount of energy required to heat the water for a shower, vs the amount wasted in storing unnecessarily hot water, is massive. Ie the wastage is insignificant. If you want to economise, do it by spending less time with the shower running. Or be like me and just don't bother to shower at all. After a while, the dirt and smell reaches equilibrium.

[Paul C]

The issue is the loss of heat from the system whilst the hot water is being stored. Heat lost is directly proportional to the temperature difference between ambient around the calorifier, and the hot water inside. Therefore storing water at a cooler temperature will waste less heat.

 

However in context, the amount of energy required to heat the water for a shower, vs the amount wasted in storing unnecessarily hot water, is massive. Ie the wastage is insignificant. If you want to economise, do it by spending less time with the shower running. Or be like me and just don't bother to shower at all. After a while, the dirt and smell reaches equilibrium.

 

Agree with the 1st bit. The 2nd bit, however, the wastage of heat due to storing hot water will be significant.

 

How about a 'power monitor' such as this: http://www.maplin.co.uk/batteries-and-power/mains-electrical/power-and-energy-monitors

[Grace and Favour]

MrSmelly - - (that moniker seems so innappropriate somehow)

 

Just put some extra insulation around your calorifier & hot supply pipes.

 

 

Then you can continue to maximise the volume of hot water drawn from your various outlets

[nicknorman]

 

Agree with the 1st bit. The 2nd bit, however, the wastage of heat due to storing hot water will be significant.

 

Depends of course on how well insulated it is and what you mean by significant.

[twbm]

Also - if you want to enjoy endless hot showers, then hotter water requires more cold to be added so the tank contents will last longer.

[GUMPY]

I belive that in a shower mixer you just use less hot water if its above the required temepeature.

So if the hot is at the correct temp you use 100% hot

If above you may use 75% hot 25% cold, so for a given length of shower you actually use less hot water.

So you end up having to heat less hot water.

 

Other half insists on it being very hot I dont have the choice to change it.

 

ETA took so long typing I was beaten to it

Edited May 13, 2013 by Loddon

[nb Innisfree]

At that price I wouldn't worry too much about it.

[mrsmelly]

At that price I wouldn't worry too much about it.

Hi

 

Yers thats exactly my sentiment the leccy bill for the entire winter was peanuts but I was just interested and have had some interesting replies if a little conflicting re the matter. Dont know wether to turn it down a notch or two or just leave it alone know.

I know just had a good idea...............will have some beer and think about it more later.

 

Genuine thanks for all replies peeps.

 

Tim

[ditchcrawler]

Depends of course on how well insulated it is and what you mean by significant.

Unless its a vacuum the heat loss is still proportional to the temperature differential between the water in the calorifer and the ambient temperature around it. Better insulation will also give savings when you run the calorifer runs at a lower temperature.

[keble]

Unless its a vacuum the heat loss is still proportional to the temperature differential between the water in the calorifer and the ambient temperature around it. Better insulation will also give savings when you run the calorifer runs at a lower temperature.

 

This is seriously but I am reminded of the discovery some years ago that warm ice cream freezes faster than cold ice cream.

 

From the fount of knowledge:

 

The Mpemba effect, named after Tanzanian student Erasto Mpemba, is the assertion that warmer water can freeze faster than colder water. Although there is anecdotal support for the effect, there is no agreement on exactly what the effect is and under what circumstances it occurs. There have been reports of similar phenomena since ancient times, although with insufficient detail for the claims to be replicated.

The phenomenon seems contrary to thermodynamics, but a number of possible explanations for the effect have been proposed. Further investigations will need to decide on a precise definition of "freezing" and control a vast number of starting parameters in order to confirm or explain the effect.

 

There's more where that came from ...

[nicknorman]

Unless its a vacuum the heat loss is still proportional to the temperature differential between the water in the calorifer and the ambient temperature around it. Better insulation will also give savings when you run the calorifer runs at a lower temperature.

Not disputed, and even in a vacuum there is heat loss due to radiation. However when you are using lots of energy to heat water and throwing it into the canal (ie a shower!) the additional energy required to maintain the tank hot once its back up to temperature, whilst still existing, might be insignificantly low in comparison.

[KJT]

 

This is seriously:smiley_offtopic: but I am reminded of the discovery some years ago that warm ice cream freezes faster than cold ice cream.

 

From the fount of knowledge:

 

The Mpemba effect, named after Tanzanian student Erasto Mpemba, is the assertion that warmer water can freeze faster than colder water. Although there is anecdotal support for the effect, there is no agreement on exactly what the effect is and under what circumstances it occurs. There have been reports of similar phenomena since ancient times, although with insufficient detail for the claims to be replicated.

The phenomenon seems contrary to thermodynamics, but a number of possible explanations for the effect have been proposed. Further investigations will need to decide on a precise definition of "freezing" and control a vast number of starting parameters in order to confirm or explain the effect.

 

There's more where that came from ...

 

Yes, that's correct. I once did some work for a well known ice cream manufacturer and was surprised to learn their ice lolly manufacturing process involved the lolly mix using hot water and the moulds containing the mix being quick frozen in sub-zero brine baths to achieve a faster freeze time. I believe it was something to do with the rate of temperature change being commensurate with the difference in temperatures. I guess that falls in the strange but true category!

 

Ken

[junior]

How often do you get your leccy bill or can you monitor your leccy useage on say a weekly or monthy basis? As with ever on a forum you have got 20 replies with 20 different answers. Perhaps a way to find out would be to record your power useage as it is now over say 5 or 7 days. Then drop down a couple of notches (I think you said from 5 to 3) but keep your showering routine and tempreture the same. After the same period as before, check your leccy useage and see if there is a noteable difference.