Changing from prepay energy meters to normal meters. Be leery of being overcharged!

I'm getting both my electricity and gas meters changed today from prepaid to the normal type of meter. Since moving into this new flat (apartment) 2 years ago, I have had to keep going to local shops to buy electricity and gas on keys/cards every month or so. It was a confounded nuisance! But this flat came with these prepaid meters, and it was going to cost me £60 to change each meter, so £120 altogether. However, recently I heard they will now do it for free. So decided to get them changed.

I'm not sure though that the company that supplies my power -- npower (I'm in the UK) -- won't try and pull a fast one and overcharge me, utilising the confusion over changing meters.

My old meter yesterday afternoon read 20579. I assume this refers to kilowatt hours. Just had my new meter installed 2 hours ago. Immediately after being installed the new meter read 21347. An increase of 21347-20579 = 768 kwhs.


Accessing my npower account, my consumption per day of electricity averaged over 2 years is 9.33kwh's. So essentially this new meter reading is around 760kwh's more than it should be, representing around 11.5 weeks of electricity usage. This represents roughly £100.

Best to see it in graphical form on excel. There's a sudden sharp rise at the end.

So, presumably these readings can't be related. I regard it highly unlikely that npower are trying to nick a £100 off me! But, I thought I'd better contact them, just in case. I was informed via webchat that these figures are not related and that their database needs to be updated, and this will take around 45 days. 

OK, that's great! But, I've just been thinking over the past 30 mins or so. I'm going from paying in advance, to paying in arrears. Let's say on the prepay meter I pay upfront for one month, say November's, but at the end of November I switch meters to a normal meter. If I still pay every month I won't pay December's electricity until the beginning of January. Then it'll be just as before, paying every month. I'll be better off of course since I skipped one month's payment. That's the advantage of going from paying in advance to paying in arrears!

Of course, in reality, one won't actually skip a month (I wouldn't imagine?). Rather over a specified number of months, let's say the next 12 months, one's monthly bill will be 11/12ths of what it was previously (assuming comparable tariffs). So I should either skip paying for a month, or more likely, be paying less over some specified number of months in the future (if 12 months, then I'll only be paying 11/12th each month for these 12 months of what I paid previously. Then it'll go back to its normal price).


However! Conceivably the opportunity is there for them to pull a fast one. They could simply screw me out of this 768kwhs, and the amount I'll pay in future months might be comparable to what I've always paid, so that I'll never notice.

That's a very cunning way to screw people out of their money! Who the heck would notice??

UPDATE Same day around 4 hours later.

A guy has just been round and changed my gas meter. I was thinking "it looks like the same guy who changed my electricity meter earlier, surely?".

After he finished he said:

"I don't know why I couldn't have done that this morning".

Yep, the same guy! When I rang up 3 weeks ago to book appointments to get these meters changed, the lady said the same guy wouldn't be able to do both, so 2 different people would need to come. Sigh...


The reading on this new gas meter is vastly higher than on my old one, so I strongly suspect what I was told in the webchat was correct.