Why are there no energy services companies (ESCOs) supplying individual UK households?

Question

In theory, energy suppliers could bill domestic customers for energy and energy savings. Ofgem say on their site they'll encourage this. But no one seems to do it. Why? Are there in other countries?

Answer 1

Answering from the US, the reason that ESCOs typically can not support the individual residential customer is the structure of the electricity and gas markets.

The markets require that energy be acquired in significant blocks - much bigger than an individual household would use.  Therefore the ESCO can't really buy for a single user.  Theoretically, the ESCO could manage a large number of individuals, but the overhead to do so is likely cost prohibitive.

One thing that has become common in the US is groups of consumers working with utilities or ESCOs to buy energy in bulk.  Often this is a city or town, but can even be a single a neighborhood.  By grouping together, the demand is high enough for the market and the ESCO simply negotiates a "group rate" for all the members.