The scheme kicked off this month (April) but will only gradually come into force with the full bill for carbon emissions not being applied until the same time next year.
However, PriceWaterhouseCoopers has urged companies to look at their energy now as research suggests that poor performers could add nearly 20 per cent on to their energy bill by 2015.
David Walters, partner, for sustainability and climate change at the firm, commented: 'Registration is the easy part of the scheme, 2011 is when the impact on cash flow will really be felt.
'Businesses need to get on top of the long term energy, cash flow and reporting requirements. Underestimating the impact will hit companies' bottom line at a time when they can least afford it.'
The research also found that companies which do plan ahead could end up cutting their costs.
For a business with annual energy costs of £1 million, falling into line with the new regulations could save as much as £85,000 a year by 2015.