Pricing
Electricity supply in the United Kingdom is deregulated and the several providers offer different tariffs, much as telephone or internet service providers do. Economy 7 can offer some consumers savings, but a careful analysis should be done. For example, if the price is double the normal tariff during the 'day' period, and half the normal during the 'night' period, then to break even the consumer would need to use over 2/3 of their energy during the 'night' period. (Typically this makes sense when heating/water is electric rather than gas.) An Economy 7 tariff can end up costing significantly more than a standard tariff without restructuring current energy usage.
Read more about this topic: Economy 7