Last month, California experienced record-breaking heat waves that resulted in the state’s grid operators collapsing as thousands of households simultaneously used their air conditioners. As a consequence, hundreds of thousands of homes were forced into rolling blackouts. With population and urbanization rapidly rising, summer temperatures are already expected to triple the demand for air conditioners in homes worldwide by 2050. According to the International Energy Agency’s Future of Cooling report, this could put the total number of units at 6 billion.
A 2019 Applied Energy study by Arizona State University and the University of California, Los Angeles predicts that Los Angeles County alone will see a 51 percent surge in electricity demand by 2060 under a high-emission scenario. That means an additional 6.5 gigawatts is needed—the equivalent of 20 million 300-watt solar panels.
Air-conditioning presents a unique paradoxical problem: as climate change continues to progress, the more cooling technology is needed. However, air conditioners themselves are a culprit in boosting temperatures and producing heat, subsequently contributing large amounts of greenhouse gases into the atmosphere. Energy demand is already estimated to reach 6,200 terawatt-hours by 2050, which is only a quarter of the world’s current total electricity consumption.
It’s this phenomenon that experts are calling the “cold crunch.” However, the challenge isn’t just meeting demand, but anticipating the rising levels during peak periods that occur during only a few days in a year.
Rethinking Cooling Technology
Several alternative solutions have been offered to address this, primarily the transitioning of electricity grids to use clean energy sources such as solar and wind. Likewise, smart grid systems that include sensors, control systems, and software capable of autonomously reducing usage when temperatures decline have also been proposed. Another potential solution is swapping out the typical hydrofluorocarbons used in cooling devices, which tend to leak out potent greenhouse gases. The industry might see more innovations in this area, particularly after a 2016 amendment to the Montreal Protocol explicitly encourages companies to seek technology with less harmful emissions.
These alternative refrigerants have the capacity to reduce around 50 billion tons worth of CO2 emissions according to an estimate from Project Drawdown. To put that into context, total global CO2 emissions was 37 billion just last year.
Transaera, a startup cofounded by MIT energy professor Mircea Dincă, is aiming to address this dilemma by focusing instead on the humidity in the air. Traditional air-conditioning units tend to consume large amounts of energy just to manage water vapor, subsequently resulting in retained heat. The company is currently studying metal-organic framework materials that can be built to capture compounds like water. Transaera has already created an attachment using these materials for air conditioners, reducing humidity in the air and improving energy efficiency by over 25 percent.
The company is currently a finalist in the $3 million Global Cooling prize and will be testing its prototypes in India in collaboration with Chinese home appliance company Haier.
Another company, SkyCool Systems from California, is taking a different approach by developing mirrors capable of casting heat back into space. This particular phenomenon is called “radiative cooling.” In this process, the radiation is emitted into a narrow band on the light spectrum, which slips past water molecules and atmospheric compounds that tend to radiate heat back toward Earth. These mirrors are designed to fit on rooftops and replace traditional building cooling systems. According to SkyCool, this can reduce the energy consumed by cooling technology by around 10 to 70 percent. The company is currently working on installing the mirrors on its fourth commercial site.
These are only a handful of ideas currently tackling this burgeoning problem. Research firm CB Insights has already noted eight financing deals worth $40 million back in 2015 going to heating, ventilation, and air-conditioning technology. The total number of deals was at 35, with approximately $350 million worth of investments just last year, including loans and acquisitions. This year, 39 deals worth $200 million are already underway.
However, compared to the amount poured into other energy and technology sectors, the funding is still relatively limited.
For more news and stories, check out this discussion on carbon capture plants here.