On Saturday, the Burj Khalifa turned off its dazzling lights to mark Earth Hour.
Meanwhile, Pakistani friends joke that Karachi celebrates Earth Hour all the time.
Earth Hour, organised by the World Wide Fund (WWF) for Nature, is held on the last Saturday of March each year. More than 6,000 cities and towns across 150 countries join in, with homes and businesses encouraged to turn off non-essential lights.
Yet to the 1.3 billion people who lack electricity - not for an hour but always - the symbolism seems entirely misplaced. And for those struggling with blackouts in Pakistan or Iraq, or in many African countries with little prospect of ever being connected to the grid, Earth Hour may seem like self-indulgence by the wealthy.
In rural Laos or Cameroon, when night falls, it is like a return to the Middle Ages, stopping the day's labours in small workshops. Locals stumble along uneven paths in darkness, cook with firewood, study, if at all, by the uncertain light of a candle or oil lamp. Mobile phones have arrived - but people spend a fortune to charge them.
The Burj Khalifa, with some 35,000 inhabitants, is connected to 74 megawatts of power. Meanwhile, the 4 million people of the Central African Republic have to make do with just 46MW. The answer is not to make Dubai, Dublin and Dallas dimmer but to illuminate Africa.
The WWF's message to the wealthier countries is also misleading. Turning off lights suggests environmentalism has to involve suffering and denial.
Yet denial is not enough. Cities participating typically experience falls in electricity consumption of between 2 and 6 per cent during Earth Hour.
Even if sustained over an entire year, this is trivial - especially in countries such as the UAE, where electricity demand rises 7 per cent or more annually.
By comparison, to avoid catastrophic climate change, we need to reduce carbon dioxide emissions by some 80 per cent by 2050.
To do this entirely by conservation would turn the UAE into something akin to Iraq, which gets six to eight hours of electricity per day during searing Baghdad summers.
For the wealthy developed countries, where the reality of grinding poverty is forgotten, it is fashionable to yearn for a return to low-energy, low-tech, zero-growth societies. The social turmoil, xenophobia, fall in support for environmental causes, and other ugly reactions unleashed by a few years of recession should show how dangerous these fantasies are.
For countries such as Brazil, India or China, where the acquisition of a refrigerator, air conditioning and a television marks the move into the new middle class, threatening to take those boons away is exactly the way to discredit environmentalism.
Of course, improved energy efficiency is vital. The confusion is between conservation - doing less - and efficiency - doing more with less.
How many owners of buildings around the world turning off their lights for Earth Hour were taking the simple, cost-effective steps that would make a real difference: installing insulation and solar water-heating; automated shading; intelligent controls on lights, computers and appliances; overhauling air conditioning; and fitting energy-efficient bulbs, pumps and motors for escalators and lifts?
A more positive Earth Hour might involve choosing a town each year in the developing world and providing modern energy-efficient cookers for residents, along with solar lights, electricity from renewable sources and clean natural gas.
Environmentalism should not be about less - it is about more: energy that is more abundant, cleaner, cheaper, more secure; economies that grow faster with new technologies; more people escaping poverty.
Darkness spreading across the planet should not be the aim of environmental campaigns - it should be a symbol of what happens when energy and environmental policy fails.
Robin Mills is the head of consulting at Manaar Energy, and the author of The Myth of the Oil Crisis and Capturing Carbon