Half a billion kilowatt hours, 414 people in a different company, and no way to put the two together

Here are the numbers, and then the reasons to handle them carefully.

Vantage Data Centers UK Limited, year to 31 December 2025, filed on 7 August. UK energy consumption of 505,866,500 kilowatt hours, against 408,199,609 the year before. That is a rise of just under a quarter in twelve months. Carbon dioxide from that electricity, 89,333 tonnes, against 84,236. Average monthly employees, excluding directors: Nil, and Nil the year before.

VDC UK Management Company Limited, same group, same year end, filed the same day. Average monthly employees including directors, 414, against 411. Operations 199, administration 215. Wages and salaries of 48,116,742 pounds, against 41,677,596. Total staff costs of 56,617,451 pounds. Turnover of 83,723,805 pounds, which is management charges rather than sales to the public, against 65,263,090. Net assets of 17,535,678 pounds.

Ark Data Centres Limited, year to 30 June 2025, filed in December 2025. Average employees 139, against 107. Total energy consumption 280,597 megawatt hours, against 239,803, of which the part running the computers was 203,608 megawatt hours, against 164,622.

For scale, Ofgem's figure for a typical household is 2,500 kilowatt hours of electricity a year. On that basis, Vantage UK's British electricity last year was roughly what 200,000 homes use. Ark's was roughly 112,000 homes.

Now the cautions, and there are four of them, because each one would let you build a headline that the documents do not support.

The first is that Ofgem's typical household figure changed on 1 July this year, falling from 2,700 kilowatt hours to 2,500 because households have been using less. The comparisons above use the current figure. Run them on the old one and Vantage becomes roughly 187,000 homes rather than 200,000. Neither is wrong. They are different years of the same measure, and anyone quoting a homes number without saying which is quoting a number they have not checked.

The second is the periods. Ark's headcount is for the year to 30 June 2025. Its energy figures are not. The company reports energy by calendar year to line up with its climate change agreement, its emissions trading obligations, its planning conditions and its environmental permits, so those figures cover calendar 2024 and 2023. Energy per employee at Ark can be calculated, but the two halves of the sum come from different twelve month periods and it should never be printed as though they did not.

The third is the one that matters most. Do not divide 505,866,500 by 414. The two numbers are in different companies. The management company's own accounts describe share schemes covering employees of the European business, so some of those 414 people support buildings that are not in Britain. Nothing in the public record says how many. A ratio built from those two figures would look precise and mean nothing.

The fourth is that the two companies are not reporting the same thing. Ark discloses the energy that runs its computers as a separate line, which the rules do not require. Vantage reports a single UK total. Putting them in the same column implies a comparison that the disclosures do not support.

What is left after all that is still worth having. One British company consumed over half a billion kilowatt hours of electricity in a year and reported no employees. Another consumed 280,597 megawatt hours and reported 139. Both figures come from audited accounts filed at Companies House, both are free to read, and neither depends on anyone's forecast.

There is one more figure worth holding, and it is the one that ages fastest. Vantage's British electricity use rose by roughly 97 million kilowatt hours in a single year. If a reader wants a number to watch, it is not the level. It is the rate.

This desk offers information and not advice, and none of the above is a view on any company as an investment.