Predicting energy bills...

GotToChange

I have had the dubious "pleasure" of moving three times since the start of November.

In the process, I have moved properties as follows:
1. Left my home of just under 13 years, where I had a total understanding of my heating system and energy usage (with S/Power on DD payment. Due (and finally received) about £100 refund when leaving.
2. Next property (didn't actually stay there but in a Travelodge for 10 days). I inherited a PP meter for electricity - with E.On - and credit meter with Br Gas. Even though I had left S/Power on good terms, they wanted a hefty deposit to change the PP meter to credit.
3. To a small bungalow supplied by S/Pwr with credit meters for both - tracked usage (combi boiler in loft, 5 rads) which was higher than my original home.
4. Moved to where I am now and again inherited PP meters with both supplied by E.On again. Took a couple of weeks but now both meters are credit. The usage of gas particularly has seemed higher than in my initial home...
...which brings me to my question to anyone who has read this far and is interested.
I am quite fond of tracking numbers and carrying out calculations, even when it is somewhat depressing - but I do believe that knowledge is power (see what I did there?). I am also trying to asses the efficiency of my system and consequent costs.
Most especially with the PP gas meters, I find that it is very difficult to look at units (which themselves can be imperial or cubic metres) and understand how the £££ used is achieved. The energy suppliers seem to think that all we want to know if what we are paying, which muddies the waters even more than they are by so many different tariffs, two-tier systems, postcode differences etc etc.
Personally (and it may be my inner geek), I think it is very helpful to be able to predict what the power we use will cost us. I have not found any software that can do this - and even when I called E.On to ask them to go through it with me (for example, finding out that the two-tier payments apply daily, not annually, as I had thought....), they did not seem to have a process for being able to.
Does anyone know of a device or some such that is around for doing this?
i.e.
input your dates (no. of days in calculated)
input your meter reading (the previous reading is deducted)
[gas only] all conversions are done for you, allowing also for metric/imperial
input tariff
input st. charge
the predicted bill is given.

I have already got a spreadsheet that can do this - but I wonder if a small calculator-like device would work better for some people.

Anybody know of anything?

HappyMJ

Your spreadsheet sounds quite good. There is imeasure that will do something similar but it won't take into account the daily first tier tariff...it will calculate it on a weekly basis assuming you were to use at least the minimum primary units on each day in the period. If one day you were to use none and the next day double then the resulting figures will be different. http://ebico.imeasure.org.uk/

Naf

I have an i-Device app that works extremely well. Calls itself 'meter readings' - logo is a blue square with kWh printed across he lower portion.
There's a free version, and you can pay a small amount to get a few more options unlocked.