Professor Matthew Johnson has developed a new way to clean indoor air that saves energy, improves health and the climate. He has patented the “CleanAir” invention that uses photochemical air purification.
Dr. Johnson came up with the idea for CleanAir while he was studying how the atmosphere cleans air. Photochemical air purification “purifies the air using chemistry, and UV light in the place of sunlight” replicating what happens in the atmosphere within a building.
"Every second we pump air into our houses that is too hot, too cold or too moist. And then we spend billions of kilowatts treating that air; cooling it, heating it or dehumidifying it. If we could clean the air, we could recycle air that already has the perfect temperature" explains Matthew Johnson.
By using the CleanAir invention less fresh air is brought into the building allowing for greater recirculation of air that is already the right temperature. On top of that, the invention cleans the recycled air of “different types of indoor air pollution: Particles, saturated hydrocarbons and unsaturated/aromatic hydrocarbons” leaving behind clean “Green Air”.
In the process, about 25 percent less energy is used to treat incoming fresh air which also translates in to savings from less required maintenance. The cleaner recycled air will also improve the health of families and employees in CleanAir treated buildings. Since the process cleans “particles, viruses, ozone, bacteria, organic solvents and hydrocarbons from air”, those with chronic illness, allergies and asthma will have fewer acute illnesses and breathing problems. The process also removes cigarette smoke improving the atmosphere for others in the smokers vicinity.
One example: A big furniture store can spend around 1.64 million DKK (apx. 216.000 euro or 296,114 dollars) per year on ventilation. About 30% fresh air is brought into the air stream by the HVAC system in order to dilute chemical vapours (e.g. aromatic solvents and formaldehyde) given off by glues, foam and wood products. The device, installed in the HVAC system and reducing the fraction of fresh air brought into the system by at least half, would pay for itself in terms of reduced HVAC cost within 2 to 3 years.
The process has been tested. When it was switched on in an office building at the University of Copenhagen where Professor Johnson works, the device cleaned 40 different compounds out of the air in minutes.
Other uses for the device are being investigated such as using it to clean the air in factories and factory smokestacks. If it proves to be as successful as expected, it will “revolutionize the cleaning of emissions from factories.” Cleaner emissions means cleaner air for the rest of us.
The University is also working with partners to get CleanAir into mass production so the rest of us can benefit from it.