Anyone who pays a utility bill knows the impact their HVAC system can have on the energy usage of their home and business. Heating, cooling and ventilating a building can comprise more than three-quarters of the electricity used in both residential and commercial buildings. This is especially true on hot, humid days and cold, frigid nights. 

One way commercial and multi-family building owners and operators can reduce the energy required to control their indoor climates is by using technology like Motili’s HVAC Efficiency Tool. It provides the real estate industry with the ability to calculate carbon emissions associated with their HVAC operations. 

The HVAC Efficiency Tool provides users with five useful statistics, including:

• Your energy costs per unit and per all HVAC properties over the span of 10 years.
• The percentage your energy use decreases. 
• The amount of carbon emissions you can save each year. 
• The gallons of gas emissions equivalent. 
• The weight of your carbon savings in elephants. 

It’s no wonder that scientists and industry experts never stop seeking more efficient HVAC methods. Now that the United States has rejoined the Paris Climate Accord, the search for increased energy efficiency has taken on a refocused urgency.

While many advancements in tackling HVAC’s environmental impact have focused on less environmentally harmful refrigerants, most progress has still resulted in chemicals that aren’t necessarily helping efforts to combat climate change – they’re just less harmful than their predecessors. New research, however, has uncovered an organic material that uses less energy to dry air, with the potential to drastically boost HVAC efficiency.

Scientists at Texas A&M University recently described an organic material known as a polyimide, which not only makes HVAC systems more energy efficient, but can even reduce the purchase price of HVAC systems that incorporate the technology.

HVAC systems typically integrate a dehumidifier that removes moisture from the air, and they usually rely on refrigerants. The chemicals are employed in cooling the air and reducing its ability to carry water vapor. However, as previously mentioned, these refrigerants are a major contributor to global climate change. 

The Texas A&M researchers replaced those harmful refrigerants with a cost-effective, organic polymer known for its rigidity and heat tolerance. According to the university’s engineers, the high-performance polyimides consist of “repeating, ring-shaped imide groups connected in long chains.” 

“In this study, we took an existing and rather robust polymer and improved its dehumidification efficiency,” said Hae-Kwon Jeong, McFerrin Professor in the Artie McFerrin Department of Chemical Engineering at Texas A&M. “These polymer-based membranes, we think, will help develop the next generation of HVAC and dehumidifier technologies that are not just more efficient than current systems, but also have a smaller carbon footprint.”

Scientists applied the polyimide molecules to tiny alumina platforms, each only a few nanometers across. Then, they placed them into a highly concentrated solution of sodium hydroxide, which triggers hydrolysis as the molecular groups break apart and become dissolvable in water. While examining the event under a microscope, researchers discovered that these hydrolysis reactions create “water-attractive percolation channels” within the repeating polymers.

Ultimately, the Texas scientists discovered that the compound’s surrounding membrane could extract excess moisture from the air. According to the study published in the Journal of Membrane Science, the polyimide membranes can potentially be used for continuous dehumidification without ever needing to be regenerated. The trapped water molecules escape from the opposite side of the vacuum pump within a standard humidifier. 

“This is a new approach to improve the property of a polymer for dehumidification, and a lot more optimizations need to be done in order to further enhance the performance of this membrane” Jeong said. “But another key factor for engineering applications is that it has to be cheap, especially if you want the technology to be reasonably affordable for homeowners.”