Home » technology

Category Archives: technology


Thermoacoustic Cooling

Although this blog was begun to publicise my own fiction, there are so many interesting things to write about that the fiction element has been displaced by other kinds of stories; stories about geopolitics, concerns about global change (of which not least, climate change), and new developments in science and technology.

Principle of a thermoacoustic engine. Image courtesy Wikipedia.org

It currently seems to me, as an informed layperson, that the answer to the planet’s global warming crisis lies primarily not so much in technological advances as in social engineering for change. For example, livestock farming produces 18% of global greenhouse gas emissions. Halving the consumption of meat, to take only one measure, would have enormous health benefits for individuals and at a stroke, reduce greenhouse gas emissions. That’s the equivalent of removing the 2015 contributions of the two most populous countries, India and China!¬† According to a 2006 FAO report, Livestock’s Long Shadow (416 pp.), cattle alone are responsible for more global warming than all forms of transportation put together.

Another quick fix would be to reduce national defence budgets and invest the money in women’s health and education, easier said than done, considering the political madness that one sees in countries around the world. This too can be changed if enough people around the world set their minds to it and realise that we, the people, are the drivers of political change. Politicians are servants. They are merely people responding to our collective angsts and biases.

As global temperatures rise, people try to cope by installing air-conditioning units. This compounds the problem, since electricity consumption multiplies and heat dissipates to the outside world, creating urban heat islands and causing yet more global warming. It’s like polluting an ocean. Imperceptible when only one person does it, but massive when done by millions. Here’s an exciting technological fix in the works that might help to solve the air-conditioning problem: thermoacoustic cooling.

Working example of a thermoacoustic engine: Image courtesy YouTube

The principle was apparently observed by glassblowers more than two centuries ago. They noticed a sound was created when blowing a hot glass bubble at the end of a cold, long tube. 19th century scientists figured the sound was produced by the thermal gradient, and resonance was giving extra energy to the air in the tube. Apparently the first modern application to capture this energy for cooling was used in NASA’s Space Shuttle Discovery in 1992. Today, there seem to be two companies, in the Netherlands and in France, who offer solutions based on this principle for pollution free cooling. Here’s a link to the websites of Dutch company, SoundEnergy and France-based Equium. The sooner such companies are commercially¬† successful, the better for the planet. Here’s a simple demonstration of the principle showing the working of a thermoacoustic engine.