Take it further to make it really useful
Instead of letting another power company spam me with offers, why don't we add a little more logic.
The database sorts through all the offers from the various companies, finds the cheapest, then bills me directly. It does this every 6 months. I only deal with Ofgem, I get the best deal, I don't have to spend days poring over my energy bills to figure out how much I use then calculate the best rate. The energy companies have to be competitive to ensure Ofgem selects their deals. We all win.