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[sheddyian]

Also, in an ideal world (I know!  )  your hot water will be heated by solar, so the running costs are low.
Ian

Solar panels in the cloudiest place up here in the north with only 7 hours worth of gloomy daylight in winter would you still get a hot bath 

They're surprisingly effective.  There are two sorts - "flat plate" which are the plain black panels, and evacuated tubes, which are like long tubular thermos flasks with a double wall, and usually also arranged inside a panel.  I understand the evacuated tube design is more efficient (loses less heat and captures more) even on a cloudy day.

I've got 2 of the first (cheaper) sort.  There is a controller that switches the pump on when the panels are hotter than the water in the hot tank.  I wired a light to this so I could easily see when it's running.  It's running most days, sun or cloud!

I once scraped a load of snow off a panel, and the thing started running even though it was below freezing - the low winter sun was still enough to get some heat from.

Of course, you can still have your gas or electric to top it up.

I set the maximum temperature to 95C on the controller, and in the summer the hot water is regularly hot enough to be scalding 

Ian

[oldfogy]

Good point Chrysalis, I wouldn't want to be paying to replace a landlords boiler either.

Something I forgot to mention this morning,  when I installed our dishwasher that was cold fill only. So I purchased a mixing valve and set it to about 30 degrees so the dishwasher always gets warm water rather than cold. Not sure you could do this with a washing machine as they have a cold rinse program.

Although I would agree with what you have done with the mixer valve, but the main problem there is that the dishwasher requires a cold fill just for rinsing between loads whilst waiting for a full load.
But then again, grease such as fat would dissolve better in warm or hot water.
Maybe the reason when I also had a dishwasher was why I connected mine to a hot feed that also fed the washing machine.

Whilst on the subject of washing machines, I hate my energy efficient washing machine because it does not fill with very much water because they now say washing does not need to be submerged as just the tumbling action is sufficient with the new washing powders.

Although it's only been a few months now and I have all my monthly consumption figures from previous years, because recently my 10 year old combi boiler was changed for a new 'Worcester Bosch' more efficient model and in comparison of previous years meter readings so-far my gas consumption has been drastically reduced, this I can only put down to the new boiler not having a pilot light but ignites only as and when required, also part of the energy saving feature is what they call 'Eco Mode' where when in Eco Mode the boiler only fires-up after the water has been running for at least 15 seconds, thus disabling it from igniting every-time a hot tap is turned on maybe just to either quickly wash hands or just to swill a item of crockery, (which is something that has always annoyed me when the bathroom tap is used) fair-enough, if you actually want hot water then you have to forfeit the energy saving and also waste a few more pints of water until the boiler ignites and the hot water eventually comes through, also on the subject of hot water, the temperature for just hot water is separate from the central heating setting and can now be turned to minimum all the time and as the boiler is next to the sink it's then no problem just to turn up the temperature for normal washing up or when the washing machine is to be used.

[NewtronStar]

When we have the open fire lit which has a back boiler in the winter time we have to much hot water and the washing machine is a cold feed it just seems a waste of electric to heat the water when we have plenty 

[Ronski]

Good choice of boiler oldfogy, Worcester Bosch are the only boiler I will use. We have the biggest model they did at the time, the 440 iirc. Our gas bill is about £45 a month.

[sevenlayermuddle]

I've now switched to using an old HP E8400 desktop in my workshop to run DSLstats (and other stuff), ordered one of those energy meters mentioned earlier to see what it draws. 

If you can fund the time, it would be good to post the results.   Some points to check when doing so...

1 - Make sure it is set to show Watts, rather than VA.

2 - Allow a good long time for the PC to settle down as immediately after start up you will see an artificially inflated value owing to fans in self test and startup programs initialising, checking for updates, virus scanning, etc.

3 - If checking TV, DVD etc, for standby power, wait at least a half hour before drawing any conclusions.   My own six year old Sony shows about 20W initially  in standby but that seems to be a 'keep warm' mode to relieve strain on circuitry if I keep changing my mind and switching off/on.   After about 10 minutes there is a just audible click of a relay, and it magically drops to between 0 and 1Watt (the minimum it will display).   I'm happy to believe it is thus consuming the 0.1 Watt stated in the Sony spec sheets, and that I'd expect of any decent TV made in the last half decade.

[scotsmist]

I was doing some sums this evening for a 100 watt desktop PC left on for a year to moniter stats.

So thats 100 watts per hour and in 24 hours you have used 2.4 kilowatts
now multiply that by 7 (week) = 16.8 kilowatts then multiply that by 4 (month) = 67.2 kilowatts

now we multiply that by 12 (year) = 806.4 kilowatts, now we have the total kilowatts for this PC running at 100 watts over 365 days it's time to convert total into real money.

Each user will have what's called there unit price for 1 kilowatt used for me its 0.156p so if I multiply 806.4 kilowatts by the unit (0.156p) we will get the total cost of running a Desktop PC for one year.

So here it is £125.79p 

Your sums are out by 4 weeks i.e. 52 weeks in one year whereas you are multiplying 4 (weeks) by 12 which is only 48 weeks. Another 4 weeks would add another 67.2 KWh per year approx £10.50

[HPsauce]

Your sums are out by 4 weeks

And the rest  , and the units are wrong too.

Kilowatt-hours is what should be used. And a year is about 8766 hours.
So a 100-watt (seems a lot!) PC will use about 877 kWh.
Typical electricity prices are 10p per kWh, i.e. £0.1

So that's about £88 per year.

If NewtronStar meant that his/her electricity was about 15p per unit (kWh) then it would be £132pa.

[oldfogy]

I have never used the 'Attachments and other options' feature in a post before so will have to see if this works.

Providing it works I have attached a .RAR (zip) file which contains a Excel spreadsheet that you can input your own wattage's and unit costs to give you a total cost for any given period.

You need to input or change the figures in RED to account for the 'Unit Cost - Hrs - Days - Frequency
(Frequency could be daily/weekly or yearly)

The spreadsheet actually contains 3 different calculators although 2 of them are or can be linked together, no-doubt (hopefully you will be able to figure them out)
I have also left some other data that I was using which hopefully might give you a starting point.

NB, You will need to remove the last 3 letters of the file-name including the . (.zip) of the file because I have RARd the upload and not used a .zip program.

*************************

Just a further point.
When calculating things it is always better when calculating a annual figure to multiply things by 365, not by 'days x weeks x months etc' which is why other posts are getting confusing results.

[sevenlayermuddle]

Alternatively just apply the very approximate conversion that a consumption of 1W will equate to £1 over a year.   

That formula is obviously approximate (about 30% adrift by my suppliers pricing)  and getting even less accurate as time passes and prices rise, but it does allow some logical deductions to be made and priorities set, such as...

500W garden flood light bulb, that keeps coming on when it shouldn't.  About £500 a year, well worth prioritising some effort to reduce.

60W PC, about £60 a year.  Well worth thinking about, depending how much benefit it is bringing.

0.1W TV on standby, about 10 pence a year.   Probably not too critical.

... and so on.   

[NewtronStar]

Alternatively just apply the very approximate conversion that a consumption of 1W will equate to £1 over a year.   

Yes that works out close to £1 per annum if the unit is left on 24/7 * 52 weeks (1 year)
1 watt per hour * 24 * 7 * 4 * 12 = 8 kilowatts per annum.

[sevenlayermuddle]

As I say, it is inaccurate to the tune of about 30% these days, so the garden floodlight will be more like £750, and the TV more like 13 pence.

But the same comparative conclusions usually still hold good.   It also provides easy calculations to be made if, say, you're in town and see some LED light bulbs.   You might say...

Let's say this bulb saves 20W when it is on, which would be, say, £20 per year saving if lit 24/7.   Now correct for that by saying it is only on for 6 hours a day, which or a quarter of the time, so let's call it £5 a year saving.  But it used less in summer, so round it down to £3.   If you like round it up a bit to allow for the real price, say £4 to £5 year...

..Which then enables you to make a well-reasoned decision, to buy or not to buy, based on savings vs the cost of the bulb.   Without any need for calculators, and without having to take any notice of the sales pitch.

[NewtronStar]

Kilowatt-hours is what should be used. And a year is about 8766 hours.
So a 100-watt (seems a lot!) PC will use about 877 kWh.
Typical electricity prices are 10p per kWh, i.e. £0.1

10p per kWh thats like 1997 prices in 1990 are unit price was 0.7p but in 2014 my unit price is 15.6p at thats the lowest taffif I can find here in N.I

[HPsauce]

I like living in the past. 
http://www.youtube.com/watch?v=EsCyC1dZiN8

[sevenlayermuddle]

I like living in the past. 
http://www.youtube.com/watch?v=EsCyC1dZiN8

Actually HP, was it you who originally suggested the 1W = £1 a year, formula? 

Somebody did, not long after I joined Kitz's forums, and I liked it.  Fairly sure it was reasonably accurate at that point,  no need to allow for 30% inaccuracies.  And only about 4/5 years or so ago...

[NewtronStar]

I like living in the past. 
http://www.youtube.com/watch?v=EsCyC1dZiN8

I enjoyed that vid but in 1969 I was only two but someone should remixed it into a thumping dance floor mix it would work very well