Every summer brings heat waves, but recent summers have also brought waves of criticisms about air conditioning. We are told that it is unnecessary, unhealthy and most of all that it contributes to climate change. It is even derided as sexist.

These views are badly unbalanced — not to mention hypocritical since many were written in air-conditioned comfort — but they are gaining some traction. And they could not be coming at a worse time. The world is on the cusp of an air conditioning revolution, as it is finally becoming available to billions of people who have thus far been deprived of its benefits. But it won’t happen unless the anti-air conditioning agenda is stopped.

If air conditioning were a medical advance, its creators would have won Nobel Prizes for the thousands of lives saved and millions improved. Before air conditioning, much of the continental U.S. would experience a measurable rise in mortality once spring turned to summer, and serious heat waves would fill morgues to capacity. That has been largely reversed by 90 percent market penetration of air conditioning over the last half century. One U.S. study estimates that air conditioning has prevented approximately 18,000 heat-related premature deaths annually.

Now extrapolate the benefits achieved in the United States to tropical developing countries like India and Nigeria and Indonesia. These nations have a nearly 10-fold higher cumulative population as well as hotter temperatures than America, but air conditioning is currently found in fewer than 10 percent of residences.

Not only would many lives be prolonged, but factors critical to development, like labor productivity, would also improve if air conditioning becomes widely available. Some believe that development in the tropics is not possible without it.

Lack of access to electricity or inability to afford an air conditioner (usually a window unit) has prevented the spread of air conditioning to those who need it most, but that is finally changing. A study conducted for the Organisation of Economic Co-operation and Development (OECD) estimates that nearly 3 billion more air conditioners will be in use worldwide by 2050.

What’s worrisome is that this OECD study reflects the fashionable disdain for air conditioning and treats these projections as anything but good news. “Rigorous action by governments will be critical to curb the potentially huge growth in demand for cooling,” it warns. The public health benefits of air conditioning only get passing mention while the emphasis is on the greenhouse gas emissions attributable to the extra electricity needed to run so many more units.

The study makes a strained vicious circle argument — air conditioners contribute to global warming, creating even greater demand for air conditioning — as if normal temperatures in New Delhi or Cairo or Bangkok aren’t hot enough to necessitate air conditioning, and that an additional fraction of a degree would make much difference.

The OECD’s solution is energy efficiency standards for air conditioners that are stringent enough to stem the growth in electricity demand. But the experience in the U.S. and other nations with such mandates is that they boost the purchase price of an air conditioner, likely enough to keep it out of reach for many millions of first time purchasers in the developing world. The United Nations has similarly prioritized environmentally correct air conditioners over affordable ones.

Other environmental policies will also jack up air conditioner costs, such as the United Nations’ Kigali Amendment that would restrict the most commonly used refrigerants in favor of more expensive alternatives. It also doesn’t help that expanded availability and affordability of electricity is hampered by growing opposition to the use of coal, most recently in Kenya.

At best, there is a dangerous indifference to the potential benefits of air conditioning in the developing world. At worst, there is a conscious effort to drive up costs and reduce its spread in the name of fighting climate change. To the extent the United Nations and national governments pursue these policies, the tremendous promise of an air-conditioned world won’t be realized.