I go to fill my car with petrol and choose a supplier offering the cheapest price of petrol per litre. To do this I don't need details of annual usage or how many miles I drive annually, all I need is the price per litre to see which provider is going to save me money. Why do utility companies need to know what my annual usage is? why cant we just compare using the price per kWh?
Best answer by Transparent
You can get more detail on OVO's Tariffs from their website.
Go to the main OVO home-page
Scroll down to the section with the green background. At the foot of this green section, click the text which says "See tariff information (TIL) with just your postcode". A Dialogue Window will open with three questions to answer. Then click on "View Tariff Information Label" The reason that Energy Comparison Sites need to know your approximate annual consumption is that almost all tariffs have an element of standing charge in addition to the cost per kWh.
This is very significant and can easily make a difference of 10%+ when comparing alternative options. There are Energy Companies which offer tariffs with no standing charge. I used one when renovating an unoccupied house. However the cost-per-unit was very high! I would never choose such a tariff if I had to live there.