I ran across this study recently and I have noticed a real difference in heat and cold:
A 2022 analysis from Oak Ridge National Laboratory (ORNL) found even more promising results. In winter, cellular shades can save up to 20 percent on heating costs, compared with blinds, per that assessment. In summer, ORNL researchers determined cooling savings were also up to 15 percent. Mahabir Bhandari, a co-author on that study and an efficiency and buildings researcher at ORNL, agrees that cellular shades are one of the most affordable and accessible options for boosting home energy efficiency. “You can go to Home Depot or Lowe’s and easily get whatever kind you want,” he says. Most are easily self-installed. The least expensive versions start around $25.