McCarthy, who was responsible for the assurance body which advised the Mayor of London and the Olympics minister, said that bringing in energy conservation experts earlier could have shaved £1m off the total £6m cost of providing power to the Games.
"Much more could have been done with regards to energy conservation. Earlier planning could have really benefited the efficiency," he added.
McCarthy also revealed that he received death threats relating to Dow Chemicals involvement in the Games. "It´s not my responsibility to judge Dow[´s links to the tragic Bhopal gas incident in 1984], but there is a case to be made for engaging partners about their past ethical records," he added.
However, McCarthy praised the overall planning efforts that went into creating the ´most sustainable Games ever´, singling out the innovations made by architects to save power in venues and the successful efforts to prevent any waste going to landfill - aided by Coca-Cola.
He also applauded TfL´s transport organisation, BMW´s co-operation and UPS´ logistical efforts.