Negatives of Air Scrubbers

An air scrubber is a device that houses a chemical reaction meant to remove carbon dioxide (CO2) from the air. Scrubbers are often used in closed environments like space shuttles and submarines to recycle exhaled oxygen while keeping CO2 at safe levels. Scuba divers sometimes use scrubbers to extend their dive time. With rising concern over global warming, scientists are looking at the possibility of using scrubbers to help fight climate change. But there are a number of downsides to consider before using such technology for scuba gear or to clean the environment.

Scuba Scrubbers

Scrubbers used with scuba gear use calcium hydroxide to capture the CO2 from your exhalations. The CO2 reacts with the calcium hydroxide to form calcium carbonate and water. The remaining oxygen and nitrogen cycles back into your breathable air. With a scrubber, a scuba diver can stay down longer without increasing the size of his gear. But there are some cons to the system. Using a scrubber keeps your buoyancy constant, which can affect your dive control. The system is also more expensive than a standard dive system. While you can stay down longer, the air mix required for a scrubber system may limit how deep you can dive. The system will also require more maintenance.

Researchers have developed a technology that captures CO2 out of the atmosphere using sheets of plastic. The method may eventually help to reduce the threat of global warming, but these systems are difficult to deploy. To bring about the widespread use of semi-portable plastic air scrubbers would require $20 million in venture capital. These scrubbers also require a large amount of energy and expense to operate. That makes them less attractive than other carbon-reduction efforts like discouraging behavior that generates carbon in the atmosphere. Scientists are working to reduce the cost, so it may become a viable option in the future.

Another possible way to remove CO2 from the air is to use calcium oxide heated by solar power to react with CO2 in the air. At this time, the amount of space that would be needed for solar panels to make this technology work effectively is vast, making the method impractical. Scientists must also weigh the best use of land dedicated to solar power--is it better used to produce clean electricity thereby lowering emissions or to remove existing CO2 from the air?