is it better to heat water in a house with electricity or gas?

armabelle

Hi there

We moved into a rented detached house a few months ago and got our first electricity bill. It was higher than I expected so would like to cut down.

We have central heating with a boiler downstairs which apparently heats the hot water while heating the house but in summer we don't use heating really so to get hot water we need to use a switch next to the upstairs bathroom to heat water via some kind of tank in the attic which then passes water into a cylinder next to the upstairs bathroom for use throughout the house.

Is it very expensive to run this tank in the attic and heat the water this way just to have water for one bath? Does anybody have any advice on the best method to having hot water in summer in a household with a system such as mine? We don't really need hot water except for one bath that my wife has with our toddler once a day. The other shower in the other bathroom is an electric shower so does not work from the hot water in the house and is heated instantely.

Any advice would be much appreciated

thank you

athtrasna

The picture you have posted is of that Irish staple, the immersion heater. This is an infamously expensive way to heat water.

In the summer I turn the radiators off but still heat the water on timer with the gas. Certainly cheaper than using the immersion.

iainBB

Gas is be better heat waterin Ireland in general. ( depends on rates etc)

armabelle

athtrasna wrote: »

The picture you have posted is of that Irish staple, the immersion heater. This is an infamously expensive way to heat water.

In the summer I turn the radiators off but still heat the water on timer with the gas. Certainly cheaper than using the immersion.

Thanks for the info

I can try the gas then for sure but if I turn the rads off or all the way down, they still heat up somewhat. Is this normal?

athtrasna

armabelle wrote: »

Thanks for the info

I can try the gas then for sure but if I turn the rads off or all the way down, they still heat up somewhat. Is this normal?

My boiler has a dial that lets me select what proportion of water I want to go to tank and what to radiators.

armabelle

athtrasna wrote: »

My boiler has a dial that lets me select what proportion of water I want to go to tank and what to radiators.

my boiler has no such dial unfortunately, I will turn down rads and try it and see what happens

thank you

_Kaiser_

It all depends on the boiler/timer

Mine has the option for heat + water or water only on a timed schedule or manual. I just use the water option for 20-25 minutes most days (in the late spring-autumn months) and that covers the shower. Total bill works out at about €30-40 a month.

Pkiernan

armabelle wrote: »

Thanks for the info

I can try the gas then for sure but if I turn the rads off or all the way down, they still heat up somewhat. Is this normal?

Turn off both valves, the one on the left and the one on the right of each radiator.

Sleeper12

The immersion is Energy rated D. If you have an electric shower this is energy rated A & is probably the cheapest way to heat water for showering.
If you are heating water for a bath or washing dishes etc then gas is cheaper than the immersion

Doolittle51

Pkiernan wrote: »

Turn off both valves, the one on the left and the one on the right of each radiator.

Do not do this.

One of the valves on each radiator is used for balancing. Adjusting it can have a major impact on the whole system and result in uneven heat distribution. To rectify it will require the services of a plumber.
If your rads are still warm after you turn off the inlet valve, then the valves are probably not closed tight enough or may be passing.
Any decent heating system installed in the last 10-15 years should have at least a hand valve for isolating the radiators during summer months, thus allowing you to heat the water only. Many newer systems will have actuated valves, and a separate channel on the time switch for hot water only.

ted1

Sleeper12 wrote: »

The immersion is Energy rated D. If you have an electric shower this is energy rated A & is probably the cheapest way to heat water for showering.
If you are heating water for a bath or washing dishes etc then gas is cheaper than the immersion

Per kWh gas is 1/3 the price of Elec. Electricity is 100% efficient do it gets an A rating.
With gas your heating water that it away from the boiler so your suffering losses between the boiler and tank.
With gas you have a annual service charge .
Immersions aren't efficient as your heating a random number miner if units , with electric showers you only hear the required amount ang don't waste energy*

* if you have a modern cylinder they I my lose something like 1 degrees per day so that's diffetent .
In summary gas is cheaper per unit but Elec may be more efficient

Sleeper12

ted1 wrote:

Per kWh gas is 1/3 the price of Elec. Electricity is 100% efficient do it gets an A rating. With gas your heating water that it away from the boiler so your suffering losses between the boiler and tank. With gas you have a annual service charge . Immersions aren't efficient as your heating a random number miner if units , with electric showers you only hear the required amount ang don't waste energy*

ted1 wrote:

* if you have a modern cylinder they I my lose something like 1 degrees per day so that's diffetent . In summary gas is cheaper per unit but Elec may be more efficient

A modern insulated cylinder with 2 side immersions actually has a D energy rated sticker attached to it. I've no idea if the energy sticker refers to the cylinder, immersion or the combination of the two but definitely D rated.

macnug

Before you turn off the rads, did you check to see if there is a valve for turning off rads, I havevone in my house, usually located in the hotpress.

Quaderno

ted1 wrote: »

Electricity is 100% efficient do it gets an A rating.

This is true, but this electricity has to be generated first, and this is anything but efficient. You would have to burn gas (or, more likely, turf) to heat water, turn it into steam, put it through a turbine to drive a generator and then transport the generated electricity over long distances. That wastes a lot of the energy contained in your original fuel and adds significant cost for all the equipment and the people involved in this complicated process.
When you transport the fuel to the place where you need it (gas, oil) and burn it right there you cut out most of the losses as well as the costs involved. I would wager a guess that heating water with gas/oil in the house would be at least twice as efficient (i.e. needing half the gas/oil) as burning the fuel for electricity and then using this electricity to do the job. We always use the oil boiler to heat the water, even in summer. With the radiators and the pumps turned off, of course.

firestarter51

my esb bills have dropped €100 bi monthly since i started using the gas and the gas has gone up bi monthly €30
an hour on the gas has sufficient water for the day

ted1

Quaderno wrote: »

This is true, but this electricity has to be generated first, and this is anything but efficient.

But that's totally irrelevant as you are only being billed on the the electricity after its converted so the losses are already accounted for . where as with gas you are paying for it in its primary form so the losses in conversion to heat is being born by the end user

armabelle

Pkiernan wrote: »

Turn off both valves, the one on the left and the one on the right of each radiator.

There are only valves on the left not right. There is a white dial that you can turn but it just goes round and round. It doesn't seem to do anything.

armabelle

firestarter51 wrote: »

my esb bills have dropped €100 bi monthly since i started using the gas and the gas has gone up bi monthly €30
an hour on the gas has sufficient water for the day

We had the boiler on today for an hour to see if it heated the water enough but the water was not sufficient for a bath. Tomorrow I will try two hours but wonder why I should have to run the boiler for two hours just for a decent bath. Is that just me or is it bit strange?

Sleeper12

This would probably be better off in the plumbing forum.

aido79

armabelle wrote: »

We had the boiler on today for an hour to see if it heated the water enough but the water was not sufficient for a bath. Tomorrow I will try two hours but wonder why I should have to run the boiler for two hours just for a decent bath. Is that just me or is it bit strange?

Sounds like you may need to get a plumber to come and have a look at it. When was the last time the boiler was serviced?
If it didn't heat enough water for a bath in an hour it's unlikely that it will heat enough in 2 hours either. What temperature have you got it set to? Probably should be set to around 60 degrees I think.

firestarter51

aido79 wrote: »

Sounds like you may need to get a plumber to come and have a look at it. When was the last time the boiler was serviced?
If it didn't heat enough water for a bath in an hour it's unlikely that it will heat enough in 2 hours either. What temperature have you got it set to? Probably should be set to around 60 degrees I think.

Yeah I agree
1 hour should be plenty for a bath, mine was on for an hour yesterday and after a bath there was still some water left for washing up etc
Service time

Quaderno

ted1 wrote: »

But that's totally irrelevant as you are only being billed on the the electricity after its converted so the losses are already accounted for . where as with gas you are paying for it in its primary form so the losses in conversion to heat is being born by the end user

No, since even if it would cost exactly the same I would still go for the most efficient option that doesn't take twice the fuel to achieve the same result.

H3llR4iser

I'll just put it there, I have nowhere near enough information, but given that it looks like you already have a gas boiler installed, I'll shoot: If you are thinking about upgrading/changing the system, you might want to inquire about installing a demand-type gas boiler. They don't have a tank and only heat the water as it is requested - e.g. you turn the tap for a shower, the boiler kicks in, you get hot water, you turn the tap off, the boiler goes back into "standby" mode.

It's a system widely used in some continental EU countries where the cost of energy is way higher than here; I've also had it in a couple of apartments I rented in Cork years ago, so it's starting to spread around Ireland too.

Then again, maybe your system isn't compatible with it, you need a professional to take a look...

dev100

armabelle wrote:

There are only valves on the left not right. There is a white dial that you can turn but it just goes round and round. It doesn't seem to do anything.

You only ever adjust one and that's the valve type the white dial as u call it isn't meant to grab on grab and adjust.

dev100

armabelle wrote:

We had the boiler on today for an hour to see if it heated the water enough but the water was not sufficient for a bath. Tomorrow I will try two hours but wonder why I should have to run the boiler for two hours just for a decent bath. Is that just me or is it bit strange?

Is the thermostat turned up high enough for higher temp ?

armabelle

dev100 wrote: »

Is the thermostat turned up high enough for higher temp ?

I had it up at around 65%, you think I should try it at hotter temp?

armabelle

dev100 wrote: »

You only ever adjust one and that's the valve type the white dial as u call it isn't meant to grab on grab and adjust.

So what is the white thing for on the other side?

aido79

armabelle wrote: »

I had it up at around 65%, you think I should try it at hotter temp?

I don't think turning up the temperature will. If anything 65 degrees is a little on the high side.
Your best bet is to call a plumber or look at getting your boiler serviced...or both.

armabelle

aido79 wrote: »

I don't think turning up the temperature will. If anything 65 degrees is a little on the high side.
Your best bet is to call a plumber or look at getting your boiler serviced...or both.

65% not 65 degrees

Peterx

If 65% isn't giving you the bath load of water in the one hour you want then yes turn it up.

Ask a friend to have a look in your hot press, as others have mentioned there may be a valve that can be closed to isolate the entire space heating part (radiators) of the system.

In Ireland with current utility prices heating water with gas is cheaper. Overall efficiency is irrelevant to the bill. €

armabelle

Peterx wrote: »

If 65% isn't giving you the bath load of water in the one hour you want then yes turn it up.

Ask a friend to have a look in your hot press, as others have mentioned there may be a valve that can be closed to isolate the entire space heating part (radiators) of the system.

In Ireland with current utility prices heating water with gas is cheaper. Overall efficiency is irrelevant to the bill. €

I think it may have been 60% not 65% actually. I am now using the boiler on 75% so will check if there is hot water after an hour.

What is a hot press?

K.Flyer

Whilst I know you are renting and its the landlords responsibility to ensure everything works correctly. I think it would be worthwhile for you to pay for an experienced plumber / heating technician to look at your heating system, to ensure its all working correctly and to fully explain the controls to you.
It is not a good idea for you to be turning random valves, especially if you do not know what they are for.
Some valves are set to certain positions for good reason and adjusting them may do more harm than good.
Pay for a professional to help you and you will benefit from his knowledge and experience.

aido79

armabelle wrote: »

I think it may have been 60% not 65% actually. I am now using the boiler on 75% so will check if there is hot water after an hour.

What is a hot press?

You are obviously not Irish

A hot press is a cupboard containing an immersion water tank.

I don't know what the percentages translate to in terms of water temperature but I don't believe that is where your problem is.

armabelle

aido79 wrote: »

You are obviously not Irish

A hot press is a cupboard containing an immersion water tank.

Upstairs next to the guest bathroom there is a cupboard with a big green cylinder. Is that an immersion water tank?

aido79 wrote: »

I don't know what the percentages translate to in terms of water temperature but I don't believe that is where your problem is.

I am not sure either but maybe with the dial up only 60% of the way it was not heating the water enough. I have set my timer up on my boiler with the dial at 75% (3/4 of the way up) to run for an hour in the morning and a half hour in the afternoon. I will see if this gives us enough hot water during the day.

aido79

armabelle wrote: »

Upstairs next to the guest bathroom there is a cupboard with a big green cylinder. Is that an immersion water tank?

Yeah that's your hotpress:)

armabelle wrote: »

I am not sure either but maybe with the dial up only 60% of the way it was not heating the water enough. I have set my timer up on my boiler with the dial at 75% (3/4 of the way up) to run for an hour in the morning and a half hour in the afternoon. I will see if this gives us enough hot water during the day.

If that doesn't work you'll need to get someone to have a look at it.

cruizer101

If you can post up some pics of the hot-press, the pipes going in and out of your immersion tank and the boiler someone might be able to help. But it is strange that and hour of boiler didn't heat up enough water, it points to there being an issue that may require a plumber.

armabelle

cruizer101 wrote: »

If you can post up some pics of the hot-press, the pipes going in and out of your immersion tank and the boiler someone might be able to help. But it is strange that and hour of boiler didn't heat up enough water, it points to there being an issue that may require a plumber.

ok but first, which is the immersion tank? is that the green cylinder?

aido79

armabelle wrote: »

ok but first, which is the immersion tank? is that the green cylinder?

Yes.

armabelle

aido79 wrote: »

Yes.

ok and is the hot press the thing in the attic? it is dark up there so cant see what it looks like but can hear it working

K.Flyer

armabelle wrote: »

ok and is the hot press the thing in the attic? it is dark up there so cant see what it looks like but can hear it working

No,
The cupboard with the green hot water cylinder is the hotpress.
In the attic you will (usually) find the cold water storage tank.

aido79

armabelle wrote: »

ok and is the hot press the thing in the attic? it is dark up there so cant see what it looks like but can hear it working

As I have already said...the hot press is the cupboard containing the green immersion tank. In Ireland 'press' is another name for cupboard. 'Cupboard' is actually rarely used. (I live abroad so I don't use the word press to describe cupboards as it causes too much confusion)

What you can hear in the attic is a separate cold water tank.

armabelle

have hot water now so turning up the temp solved the issue. I am going to reduce the heating time until I can get away with having hot water for the day so I use least amount of gas possible

Peterx

That's good. A cold bath is no fun.

You are still wasting heat into your radiators though as the individual radiator valves are passing.
If someone who knows about it calls around ask them to look in the immersion tank area so see if there is an isolation valve for the radiator system.

aido79

armabelle wrote: »

have hot water now so turning up the temp solved the issue. I am going to reduce the heating time until I can get away with having hot water for the day so I use least amount of gas possible

Just remember you are the person paying the heating bill and turning the boiler up to 75% will cost you more over the billing period so I would still advise getting someone in to look at it.

armabelle

aido79 wrote: »

Just remember you are the person paying the heating bill and turning the boiler up to 75% will cost you more over the billing period so I would still advise getting someone in to look at it.

Yes I know. I am going to do tests once I have figured out how much gas / cost is necessary to give us hot water per day then will compare with electricity method. Once I have those figures will see if too much or not and which is better. If not reaosnable will discuss with the owner of the house.

aido79

armabelle wrote: »

Yes I know. I am going to do tests once I have figured out how much gas / cost is necessary to give us hot water per day then will compare with electricity method. Once I have those figures will see if too much or not and which is better. If not reaosnable will discuss with the owner of the house.

I'm not sure I understand your logic but I'll leave it up to you.
An efficient gas boiler is hands down a cheaper way to heat water than with electricity. An inefficient gas boiler may be a more expensive way to heat water than electricity.

armabelle

aido79 wrote: »

I'm not sure I understand your logic but I'll leave it up to you.
An efficient gas boiler is hands down a cheaper way to heat water than with electricity. An inefficient gas boiler may be a more expensive way to heat water than electricity.

I sometimes do tests to see how much things cost in the house to see which things use up a lot of energy that we trying to live economically by reducing the amount of time the expensive things get used. I need to know how much hot water costs in the house but first I need to try to get hot water in the most efficient manner. Yesterday I had hot water by using my boiler at 75% for about 80 minutes. I am going to reduce it to 60 minutes today to see if it is still giving us hot water and keep reducing it until I can get away with still having hot water. Then I will do a reading for one day and see how much it costs.

armabelle

Peterx wrote: »

That's good. A cold bath is no fun.

You are still wasting heat into your radiators though as the individual radiator valves are passing.
If someone who knows about it calls around ask them to look in the immersion tank area so see if there is an isolation valve for the radiator system.

The only thing I see by the immersion tank is this red valve. Please see photos I took, can you anything that could help me so I don't have to use my rads at all?

gctest50

armabelle wrote: »

I am going to reduce it to 60 minutes today to see if it is still giving us hot water and keep reducing it until I can get away with still having hot water....

You need to be careful doing that craic - can turn the tank into a breeding ground for all sorts of things

aido79

armabelle wrote: »

I sometimes do tests to see how much things cost in the house to see which things use up a lot of energy that we trying to live economically by reducing the amount of time the expensive things get used. I need to know how much hot water costs in the house but first I need to try to get hot water in the most efficient manner. Yesterday I had hot water by using my boiler at 75% for about 80 minutes. I am going to reduce it to 60 minutes today to see if it is still giving us hot water and keep reducing it until I can get away with still having hot water. Then I will do a reading for one day and see how much it costs.

I understand why you may want to do these tests but an inefficient boiler will skew any results you may get and probably work out more expensive in the longrun than getting a plumber to have a look at it or to get the boiler serviced. I really don't think running the boiler at 75% is the right thing to do... but it's your money at the end of the day.

armabelle

aido79 wrote: »

I understand why you may want to do these tests but an inefficient boiler will skew any results you may get and probably work out more expensive in the longrun than getting a plumber to have a look at it or to get the boiler serviced. I really don't think running the boiler at 75% is the right thing to do... but it's your money at the end of the day.

I don't know if my boiler is inneficient yet, that is why I am doing tests