PHOENIX - At the Arizona Corporation Commission’s July 13, 2021, Open Public Meeting, Commissioner Jim O’Connor successfully convinced three additional Commissioners to join his vote to support his proposal for Arizona Public Service Company (“APS”) to implement a new Energy Efficiency program which allows greater outside air to flow indoors to often-crowded school classrooms by upgrading their existing air conditioning equipment and saving electricity at the same time.
The $2 million annual program, known as Advanced Rooftop Control or ARC, is effective immediately as part of APS’s 2021 Demand Side Management. All K-12 schools including Title 1, public, private, charter and tuition-based schools in APS territory are eligible, along with non-profit facilities which provide emergency services and housing to the needy and homeless. The CDC lists adequate ventilation as one of the most important components of healthy indoor air. ARC has up to four components, variable speed drives, fresh air economizers, smart thermostats with air quality sensors and a web-based energy management system.
“The ARC proposal is timely as many students and shelter residents continue to be put at risk of Covid-19 while indoors,” said Commissioner O’Connor. The wearing of masks and other costly and uncomfortable behavior modifications occur due to infectious diseases circulating at higher concentrations of stale indoor air. “This program alleviates some of these concerns,” said Commissioner O’Connor.
Higher indoor concentrations of carbon dioxide can temporarily lower students’ cognitive abilities and make them feel sleepy. In 2005, the Wisconsin Department of Health concluded indoor carbon dioxide is considered typical from 350-1000 parts per million, but drowsiness and poor air quality can be found from 1000-2000 parts per million and at 2000 to 5000 parts per million, it causes headaches, sleepiness, and concentration loss.
“While most existing air conditioning systems allow only about 10% to 20% of outside fresh air into a building, ARC allows the necessary amount of fresh air inside to preserve a safe low level of carbon dioxide using smart thermostats with CO2 sensors located in each classroom which can be set remotely and independently of each other using a web-based application,” said Commission O’Connor.
Additionally, ARC has numerous electricity saving features which reduce energy consumption and reduce on-peak energy usage. For example, the installation of a variable speed drive, essentially a throttle for an air conditioning blower motor, reduces energy consumption. With many schools oftentimes cooling empty classrooms because only one area of a campus is in use, ARC enables temperatures to rise in one part of campus, while students and faculty enjoy a comfortable indoor environment in another part of campus.