Immersion or oil boiler

Cardew

bobmedley wrote: »

OK, here is the appliance of science to see if E7 could work for me.

However, I use 10,000kw for the rest of my usage so I am penalised 1.83p per kw for the day rate giving a total of £183 ergo moving to E7 would cost me £80 p.a. extra. In fact, if I used full price electricity for the the HW it would still only be around £50 more than using the E7 tariff - it's hard to see how I could ever gain significant savings using E7.

..:p

You will only be saving money if your boiler is c63% efficient or lower

It might not work for you, but this is based on your huge consumption of 10,000kWh a year for the rest of your usage.

That 10,000kWh alone is over 3 times the UK average for electricity.

You have also ignored the fact that some of that 10.000kWh would be used at E7 rates any way. I have an E7 meter and although I am not on E7 some 15% - 20% of my electricity is used in the 7 hours(fridges/freezers late nights and early mornings)

Using your figures if you were an average user of electricity(3,300kWh) then E7 would save you money - even with an 85% efficient boiler,

However my point is you simply cannot say if Codo will save or not based a 63% efficiency

It depends on how much 'other' electricity he uses and the differential between E7 and normal rates as well as the rate for E7 itself.

As I said earlier - there is no 'one size fits all' answer.

paceinternet

bobmedley, there are some refinements needed to the calcs.
Things like fridges and freezers and standby items which are on 24/7 will use some of their kwh on E7 so you have to try and assess that in your calcs.
Then if you deliberately move some activities like washing mc and dishwasher into the E7 zone, the outcome is much closer.
The E7 rate from Atlantic is on the high side compared with some parts of the country which are nearer 4p. Oil will vary geographically a bit as well.

So, as has been said, it is difficult and probably not much in it for some people. Armed with these numbers, I shall look again at my own situation.

Edit: apologies the above has mostly been said whilst I was typing this.
But it also serves to remind us that for example, if you brought heat pumps into consideration and were running them mostly outside of E7 hours, then E7 may not be the answer.

Interesting though, do you think running the oil boiler for 6 months on and 6 months off could extend its life and half maintenance costs?

bobmedley

From the top;

I said the calculation was for me to discover if E7 is viable - using my own figures it's not

10,000kw is my average yearly usage - I work from home & my wife does not work, we have PC's, laptops, TV's (she won't miss Jeremy Kyle:rolleyes: ) air conditioners (sorry, heat pumps - sounds 'greener') and enough halogen downlighters to be seen from space running all day

Atlantic is expensive - I'm in the process of switching to Click5 with BG:D

Codo says that he (she?) pays 10p for a kw, so they are not on E7, so if the boiler is at least 63% efficient then they are not saving anything. If the true efficiency is found then they can make a better informed decision

My oil boiler service must be done to keep the warranty valid. This has to be annual, so using the boiler less has no impact - regarding longevity from it being used a little less I'm not sure, it's lasted 9 years already with no issues at all

Moving a dishwasher & washing machine cycle into the night would only push around a couple of kw into E7, so about 730kw totalling another £17 saving - hardly worth the effort and still an overall loss for me.

Fridges (and other constantly running appliances) running at E7 during the night will have any savings off-set by the fact you are paying a higher rate for them during the rest of the non E7 period, so money saving there is minimal to non-existant

Finally

"As I said earlier - there is no 'one size fits all' answer."

I know;)

Mazio_2

paceinternet wrote: »

Interesting though, do you think running the oil boiler for 6 months on and 6 months off could extend its life and half maintenance costs?

I would not recommend leaving it switched off for too long the best thing is to run it for 1/2 an hour or so every few weeks pumps and other components can sieze.
Like everything that has moving parts that wear it should have a benificial effect if it is not running as much but you can buy a new car and it can breakdown every 5 minutes there are as always other factors but iam assuming that it will save me on my gas boiler maintenance.

I also left E7 because it would cost me more but when I said that to EON they said use more items at night to which I replied we are "not nocturnal" and I have 4 children that eat electricity.

Cardew

bobmedley wrote: »

From the top;

I said the calculation was for me to discover if E7 is viable - using my own figures it's not

10,000kw is my average yearly usage - I work from home & my wife does not work, we have PC's, laptops, TV's (she won't miss Jeremy Kyle:rolleyes: ) air conditioners (sorry, heat pumps - sounds 'greener') and enough halogen downlighters to be seen from space running all day

Atlantic is expensive - I'm in the process of switching to Click5 with BG:D

Codo says that he (she?) pays 10p for a kw, so they are not on E7, so if the boiler is at least 63% efficient then they are not saving anything. If the true efficiency is found then they can make a better informed decision

My oil boiler service must be done to keep the warranty valid. This has to be annual, so using the boiler less has no impact - regarding longevity from it being used a little less I'm not sure, it's lasted 9 years already with no issues at all

Moving a dishwasher & washing machine cycle into the night would only push around a couple of kw into E7, so about 730kw totalling another £17 saving - hardly worth the effort and still an overall loss for me.

Fridges (and other constantly running appliances) running at E7 during the night will have any savings off-set by the fact you are paying a higher rate for them during the rest of the non E7 period, so money saving there is minimal to non-existant

Finally

"As I said earlier - there is no 'one size fits all' answer."

I know;)

Bobmedley,
It was agreed that the E7 might not work for you, that wasn't in dispute - the only point was that you ignore any of your 10,000kWh that would be used during the E7 period in the normal course of matters i.e. not increasing the electrical load during that period. Even using a modest 10% at night would cause you to break even.

Incidentally your 'double accounting' logic won't wash either. You took into account the extra price of daytime electricity in the calculations you gave(the £183) so you can't now claim that "Fridges (and other constantly running appliances) running at E7 during the night will have any savings off-set by the fact you are paying a higher rate for them during the rest of the non E7 period, so money saving there is minimal to non-existant"

Anything running in the 7 hours will save you 7.13p per kWh to offset against that £183 you used.


However you clearly don't need advice on this matter, so the above is merely a comment.

The point being made is that your assertion that Codo will not find E7 viable with a boiler having an efficiency of 63% or more is simply not sustainable.

There are 3 major points that you have totally ignored in reaching that conclusion.

Firstly you have no idea how much 'other' electricity he uses. Basing your assessment of Codo's position, using your consumption of over 3 times the UK average is pointless.

Secondly you have ignored the inescapable fact that all houses will use a percentage of their electricity during the 7 hours at night. As said above, I use between 15% and 20% during E7 hours - obviously with no attempt to move any consumption to those hours.

Thirdly you don't know the prices Codo would pay for E7 electricity.

P.S.

Moving a dishwasher & washing machine cycle into the night would only push around a couple of kw into E7, so about 730kw totalling another £17 saving

Don't understand that caculation. (I assume you have incorrectly used your oil cost of 7.38p?)
730kW moved to E7 even at the high rate of 5.06 would save you £39 if you compared it with your normal daytime rate of 10.36p and £52 if you used the E7 daytime rate of 12.19p.