The heating and cooling energy consumption of buildings accounts for about 15% of national total energy consumption in the United States. In response to this challenge, many promising technologies with minimum carbon footprint have been proposed. However, most of the approaches are static and monofunctional, which can only reduce building energy consumption in certain conditions and climate zones. Here, we demonstrate a dual-mode device with electrostatically-controlled thermal contact conductance, which can achieve up to 71.6 W/m² of cooling power density and up to 643.4 W/m² of heating power density (over 93% of solar energy utilized) because of the suppression of thermal contact resistance and the engineering of surface morphology and optical property. Building energy simulation shows our dual-mode device, if widely deployed in the United States, can save 19.2% heating and cooling energy, which is 1.7 times higher than cooling-only and 2.2 times higher than heating-only approaches.

建筑物的供暖和制冷能耗约占美国国家总能耗的15％。为了应对这一挑战，已经提出了许多具有最小碳足迹的有前途的技术。但是，大多数方法都是静态的和单功能的，只能在特定条件和气候区域内减少建筑能耗。在这里，我们演示了一种具有静电控制的热接触电导率的双模设备，该设备可实现高达71.6 W / m ²的冷却功率密度和643.4 W / m ²的冷却功率密度。的热功率密度（超过93％的太阳能利用量）是由于热接触电阻的抑制以及表面形态和光学性质的工程化所致。建筑能耗模拟显示，如果我们的双模设备在美国广泛部署，则可以节省19.2％的供暖和制冷能源，这比仅制冷方法高1.7倍，比仅制冷方法高2.2倍。