Some Tampa Bay schools are experimenting with a new, cost-effective cooling technology known as thermal energy storage. Thermal energy storage systems use massive amounts of water and glycol (think 17,000 gallons) set inside giant ice tanks to cool large structures. Originally used to keep ice skating rinks frozen, thermal energy storage is now being used to keep large buildings, such as schools, at a comfortable temperature without the high costs of traditional a/c systems. Though thermal energy storage systems cost an average of $500,000 upfront, they generally pay for themselves in 6 to 10 years by saving buildings an average of $75,000 to $100,000 in energy costs each year. TECO also offers a energy rebate for thermal energy storage systems.
The system works by freezing tanks of water during off-peak hours (such as overnight). During peak hours, a mixture of gycol and water travels through tubes placed inside the ice tanks. The ice keeps the mixture around 19 degrees inside the tubes while a heat exchanger introduces warmth from outside the system. Fans blow over the cooled mixture, creating a comfortable blast of cool air that is pumped into the building.
This system of off-peak thermal cooling can save businesses up to 50% on their energy bills. Though it’s not practical for small businesses or homes, it’s amazing what technology can do for us to keep us cool and saving money!