When Denmark's new government ministers presented themselves to Queen Margrethe II last month, the incoming development minister established his green credentials by rolling up to the palace in a tiny, three-wheeled, electric-powered vehicle.
The photo opportunity made a powerful statement about the minister's commitment to the environment - but probably not the one he intended.
Christian Friis Bach's electric-powered vehicle was incapable of covering the 30km from his house to the palace without running out of power. So he put the electric mini-car inside a horse trailer and dragged it behind his petrol-powered Citroen for three-quarters of the trip, switching back to the mini-car when he neared the television cameras.
The stunt produced more carbon emissions than if he had driven his car the entire distance. Unfortunately, the story is not a one-off.
In 2006, the UK's Conservative party leader, David Cameron, then in opposition, attracted attention for trying to "green" his credentials by cycling to work, but the tactic went awry when it emerged that a car trailed him carrying his briefcase.
But environmental hypocrisy in politics runs deeper than photo opportunities.
In Denmark, as across the developed world, politicians are promising to fix the globe's financial mess by overseeing a transition to a greener economy.
In the US, Barack Obama, the president, touts "green jobs". Australia's prime minister, Julia Gillard, has introduced a carbon tax to "enable economic growth without increases in carbon pollution". And Mr Cameron became prime minister promising to lead the UK's "greenest government ever".
Denmark is a useful test of whether these leaders' preferred policies yield the environmental and economic benefits that they promise.
In tune with international enthusiasm for green-energy investment, the Danish government intends to expand wind power dramatically by 2020. That is a significant gesture, but, since the country is part of the EU's emissions-trading scheme, it will mean absolutely nothing for global carbon dioxide emissions. It will simply make coal power cheaper in other EU countries.
Indeed, costly emission cuts in Denmark and elsewhere are likely to lead to a partial relocation of CO2 emissions to more lenient countries, such as China, where production is less climate-efficient, and thus to an overall increase in global CO2 emissions. The EU has reduced its emissions since 1990, but, at the same time, it has increased imports from China, which alone has produced enough emissions to offset those cuts.
Few expect a deal to emerge from next month's climate-change summit in Durban, and with good reason: even with Democrats in the White House and controlling the Senate, the US could not implement an agreement on climate change, while emerging economies, led by China and India, are unwilling to implement measures that would impede growth.
Danish politicians - like politicians elsewhere - claim that a green economy will cost nothing, or may even be a source of new growth. Unfortunately, this is not true.
Globally, there is a clear correlation between higher growth rates and higher CO2 emissions. Furthermore, nearly every green energy source is still more expensive than fossil fuels, even when calculating pollution costs.
We do not burn fossil fuels simply to annoy environmentalists. We burn them because fossil fuels have facilitated virtually all of the material advances that civilisation has achieved over the past few hundred years.
Politicians in Denmark and elsewhere argue as if this were no longer true: a transition to a green economy would create millions of new "green jobs". But, while green-energy subsidies generate more jobs in green-energy sectors, they also displace jobs elsewhere.
This is not surprising: either customers or taxpayers must finance subsidies. Electricity prices will rise, implying a drag on private-sector job creation. If the goal is to create jobs, public investment in other areas - such as health care - generates faster employment growth.
To bring the point home, for years, Danish politicians have insisted on subsidising the world's largest, Danish-based, wind-turbine producer, Vestas, arguing that Denmark wins when other countries spend subsidies on Danish wind-farm technology. But an official study has shown that the country has lost money overall from expenditures on subsidies.
More serious is that in today's tough financial times, the solar and wind industries are downsizing production in expensive countries and shifting employment to cheaper economies.
Many politicians are drawn to photo opportunities and lofty rhetoric about "building a green economy". Unfortunately, the green-energy policies currently being pursued are not helping the environment or the economy. More likely, they will lead to greater emissions in China, more outsourcing to India, and lower growth rates for the well-intentioned "green" countries.
Bjørn Lomborg is the author of The Skeptical Environmentalist and Cool It, and head of the Copenhagen Consensus Center
* Project Syndicate
Michael Karam is away