What do day primary, day secondary, and night units mean?

samsky

Hi,

Just received my first electricity bill today. This sounds like a very basic question, but I could not find the answer anywhere on my bill, supplier website or in the forum. Was wondering what are the timing for day and night usage, and what is the difference between primary and seconday during the day?

Thanks!

crossleydd42

Often quarterly bills have a flat standing charge, then day units, then cheap night units. In your case, I suspect that there is no standing charge and that this charge is being clawed back in the form of so many expensive, primary units. Then, the next ones are the 'normal' day units, and finally the night units, which usually cover the 7 hours between midnight and 7am GMT (1am to 8pm Summertime). Hope this is useful.

flossy_splodge

Are you on economy 7? That works differently. If you are not then the answer is quite simple.
The electricity companies have thought up this new scheme to maximise their profits, pure and simple. The first 'x' number of units will be charged at the highest rate to ensure that no matter how little you use you will still get stung. Thereafter the remainder of the units are charged at a slightly lower rate so they can kid you they are being generous. The only benefit to knowing these figures is so you can go to a price comparison site, enter YOUR data and check if there is a cheaper provider out there. You can't tell that if you dont know how much you are using and what you are being charged!
So worry not, you're screwed by the utility companies whether you understand their bills or not. :eek:

samsky

Great that's reassuring!

Yup, there's a line in my bill that says "No Standing Charge - Economy 7".

For the 2 month period, I've got 138 primary and 367 secondary units. What is the typical number of first units that the companies charge the highest rate on? Is 138 reasonable?

jaxxy00

Ive just been and checked my bill online at Powergens site so i could answer your question and have found my primary unit amounts variable. My last bill was 195 units, before that was 180, and before that was 206.

Ive just had a thought though, yours was for just 2 months and most bills are quarterly so if you work it out your 2 months at 138 it would be about 207 units for the quarter, which would be about right. Thats probably why mine has varied slightly as if i looked back i doubt if the meter was read exactly every 91 days (yes i know theres a odd one 91x4=365 days!) which allows for the slight variance.

So your primary units amount seem about right. I wonder if all companies have to stick to the same amounts?

TimBuckTeeth

The two rate, no standing charge tariffs make things confusing, the one rate standing charge tariff is easier to understand.

With a standing charge you pay a certain amount (eg. 16 pence) per day for the cost of supply of electricity to your house (similar to BT line rental), whether any units are used or not. Giving roughly a £15 charge per quarter.
Then the price per unit (kWh) is charged at one rate (around 10 pence) however much used.

The two rate, no standing charge tariffs usually have the first 225kWh units each quarter (91 days) charged at a higher rate, which covers the supply cost (equivalent to standing charge).

If you use more than the threshold of 225kWh a quarter then a simple calculation can be used to find out the equivalent standing charge :

( t x (r1 - r2) ) / p

where :
r1 is rate 1 charge per unit (primary units, higher rate) (eg. 15p)
r2 is rate 2 charge per unit (secondary units, lower rate) (eg. 10p)
t is threshold between rate 1 and 2 charges (eg. 225 kWh) for each billing period
p is billing period (eg. 91 days for a quarter)

eg. ( 225 x (15 - 10) ) / 91 = 12.36p per day equivalent standing charge
with all units used charged at rate 2 price.


Some supply companies only use the 2 rate tariff, maybe because it appears to be better value with no standing charge or because it is harder to compare with 1 rate tariffs.
You could save a little money if you use very little electricity, eg. the house is empty, on the 2 rate tariff.
For example, Scottish Power have both a 1 rate (standing charge) and a 2 rate tariff. They work out to be almost identical cost for normal use.

Cardew

flossy_splodge wrote:

Are you on economy 7? That works differently. If you are not then the answer is quite simple.
The electricity companies have thought up this new scheme to maximise their profits, pure and simple. The first 'x' number of units will be charged at the highest rate to ensure that no matter how little you use you will still get stung. Thereafter the remainder of the units are charged at a slightly lower rate so they can kid you they are being generous. The only benefit to knowing these figures is so you can go to a price comparison site, enter YOUR data and check if there is a cheaper provider out there. You can't tell that if you dont know how much you are using and what you are being charged!
So worry not, you're screwed by the utility companies whether you understand their bills or not. :eek:

I am no fan of utility companies but that is simply not true.

The increased charges for the first units used each quarter are in lieu of the standing charge that previously applied to both gas and electricity accounts. If you use all the tier 1 units, the increased charges equate to the standing charge.

Therefore if you use less than the tier 1 amount of units you actually save money. A case in point is a little used annex with a separate gas and electricity supply that I have. I used to pay the full standing charge for both gas and electricity each quarter(plus whatever I used), now the running costs have been reduced considerably.

So contrary to the statement that the scheme is thought up by the utility companies to maximise profits, it actually saves some customers money. Other customers – the majority – simply break even.

It is also pertinent to point out that prices charged by the utility companies are controlled by the regulators and all price changes have to be approved.

Ken68

Can you wonder why EBICO is so popular.