Amerada are now part of Powergen.
In 2003 Amerada and TXU Energi were both incorporated and re-branded Powergen.
Amerada customers had benefited from static prices for two years prior to being incorporated with Powergen. Price increases seemed quite large because of this but an increase in price was necessary to bring them up to date with the rest of the energy companies in the market.
Please see the Powergen page for more information about the company and the services they offer.