No 10 Downing Street, long notorious for lavishly wasting energy, last week rebuffed requests from the Independent on Sunday for information on its present performance. The Prime Minister's staff declined to disclose a simple measure of waste on the grounds that it was too "complex" to be "readily available" and refused "for security reasons" to say whether its loft was insulated.
The state of No 10 is just part of a thorough-going government failure to meet conservation targets it has itself set for its buildings, while exhorting the public to save energy. The last published figures showed that the Cabinet Office, which includes Downing Street, had achieved only a third of its objective.
By contrast, the United States is in the fourth year of a pioneering programme of "greening the White House" which is already saving nearly $200,000 (pounds 120,000) in energy costs a year - and publishes regular and detailed progress reports.
Launching the programme, in April 1993, President Bill Clinton told the public: "Before I ask you to do the best you can in your house, I ought to make sure I'm doing the best I can in my house."
The exercise by MPs - a publicity stunt organised by a charity, Neighbourhood Energy Action, which is hoping that the Budget will increase its grants for insulating homes - suggests that in Britain it is the poorest, rather than the grandest, houses that are setting the example.
The charity says that the MPs - who include the Home Secretary, Michael Howard, the National Heritage Secretary, Virginia Bottomley, the junior environment ministers Robert Jones and James Clappison,Labour 's environment spokesmen, Frank Dobson and Michael Meacher, and the Deputy Leader of the Liberal Democrats, Alan Beith - are "visiting low-income households in their constituencies to learn how improving energy efficiency in the homes of elderly and disabled people, one-parent families and other vulnerable households can provide them with greater comfort and reduced fuel bills".
No 10 Downing Street has an appalling reputation for squandering energy. Some years ago, a prominent adviser on the greening of the White House, Amory Lovins, said: "I have been in quite a number of government buildings around the world. No. 10 is the least efficient that I can recall, with the possible exception of one head of state's office in Asia." Where was that? "It would not be tactful to say."
Andrew Warren, director of the Association for the Conservation of Energy, recalls investigating the building at around the same time and finding a host of failings including draughty windows, dripping hot- water taps, radiators without individual heat controls and an absence of energy-efficient light bulbs.
Andrea Cook, director of Neighbourhood Energy Action, said last week that she had recently visited No 10, but declined to give details of its present energy efficiency. But the Prime Minister's staff says that all windows have now been draught-proofed and radiators now have their own controls. Some energy-efficient light bulbs were screwed in for the benefit of Blue Peter's cameras in 1993, and they are now used "where appropriate".
But Downing Street will not say whether there is double- glazing, or give any information on the extent or thickness of the loft insulation "for security reasons." And it will not provide a crucial figure for measuring energy efficiency - the heating cost per square metre - saying: "This figure is not readily available because there is both a gas and an electric element which make computation complex."
Andrew Dismore, opposition leader of Westminster City Council, which covers Downing Street, says: "It is remarkable that they are being so cagey about such a relatively straightforward issue, and makes one wonder just how much they have done to save energy.
"If Mr Major had set an example, as President Clinton has done, he of all people would be banging the drum about it."
In a special White Paper on the Environment, published in 1990, ministers undertook to save 15 per cent of the energy bill of their buildings within five years.
The White Paper said: "The Government is alive to its responsibility for saving energy in its own buildings as well as encouraging others to save energy in theirs."
By 1994 the civil government departments had saved only 0.3 per cent of their bills, measured in energy costs per square metre. The Ministry of Defence - which measured its performance in a different, and obscure, way - seemed to have done much better, partly as a result of the peace dividend, saving 9 per cent of its bills. This brought up the Government average of 6 per cent, still less than half of its target. The Cabinet Office had saved 5 per cent.
Several government departments - including the Treasury, the Home Office, Health, National Heritage, and Trade and Industry - had not invested a single penny in energy saving.
Since this embarrassing disclosure, ministers have not published any further figures on their progress towards their targets, though some are now 18 months overdue. The Department of the Environment says it hopes to publish more figures early next month, but cannot explain the delay.
Tim Yeo MP, a former junior environment minister, says: "It is very disappointing that we do not have up-to-date figures to see what progress has been made on energy efficiency within the Government's own buildings. It certainly indicates that the Government does not attach as great a priority to the issue as it should."
And a senior official added: "Most of the Government is just not interested."
In the US, however, President Clinton has set out to make the White House "a model of efficiency and waste reduction for other federal agencies, for state and local governments, for business and for families in their homes".
Mr Clinton added, perhaps unfortunately in the light of subsequent scandals: "For as long as I live in the White House, I want Americans to see it as a symbol of clean government, but also a clean environment."
The White House has now been almost completely fitted with the latest energy-saving lighting, while the amount of energy used in floodlighting it has been cut by more than half. Ninety-eight per cent of the windows in the Old Executive Office Building next door, part of the White House complex, have now been double-glazed and its skylights have been renovated to let in as much daylight as possible.
The White House has just completed fitting a new low-energy air-conditioning system, and replaced 99.5 per cent of its computers with energy-efficient models, while the Clintons installed the country's first "Golden Carrot" fridge which uses only half as much energy as conventional ones.
As well as saving some $200,000 a year, the measures are cutting emissions of the greenhouse gases that cause global warming.
Other government buildings, including the Pentagon, are now following suit.Reuse content