With prices going up, millions of the big 6's customers certainly feel the firms are making too much cash.
Politicians are only too happy to accuse them of making excessive profits.
But the numbers just out from Ofgem give some clarity to exactly what is going on.
In fact, the total profits made by the big energy companies actually fell last year by 3.4 per cent.
That's right across supply and generation - the two sides of the business that produce and then sell power.
But there are contrasts within those results.
The margins on the generation business fell, although was still at 20 per cent.
But five of the big six made money, and rather a lot of it from supplying electricity and gas to homes and businesses.
Ofgem calculates that profits in the domestic supply business in fact went up by a whopping 75 per cent.
The average margin crept up from 2.8 per cent to 4.3 per cent in 2012, with Centrica the owner of British Gas making a margin of over 6 per cent.
Ofgem says the companies made more because they'd put prices up, and we used much more energy in the cold winter with companies making on average 53 pounds per customer each year.
And it's not uniform, EDF actually lost money on selling to us.
The figures won't exactly endear the companies to consumers any further.
But as the Government prepares to act on energy bills, possibly removing green charges in the Chancellor's autumn statement next week, it is important to understand where the companies are making money, and where they are not.