Center for the Built Environment (CBE), University of California, Berkeley, CA, USA.
School of Architecture, University of Waterloo, Cambridge, ON, Canada.
Sci Rep. 2024 May 31;14(1):12568. doi: 10.1038/s41598-024-62377-5.
Sleep is a pillar of human health and wellbeing. In high- and middle-income countries, there is a great reliance on heating, ventilation, and air conditioning systems (HVAC) to control the interior thermal environment in the bedroom. However, these systems are expensive to buy, maintain, and operate while being energy and environmentally intensive-problems that may increase due to climate change. Easily-accessible passive and low-energy strategies, such as fans and electrical heated blankets, address these challenges but their comparative effectiveness for providing comfort in sleep environments has not been studied. We used a thermal manikin to experimentally show that many passive and low-energy strategies are highly effective in supplementing or replacing HVAC systems during sleep. Using passive strategies in combination with low-energy strategies that elevate air movement like ceiling or pedestal fans enhances the cooling effect by three times compared to using fans alone. We extrapolated our experimental findings to estimate heating and cooling effects in two historical case studies: the 2015 Pakistan heat wave and the 2021 Texas power crisis. Passive and low-energy strategies reduced sleep-time heat or cold exposure by 69-91%. The low-energy strategies we tested require one to two orders of magnitude less energy than HVAC systems, and the passive strategies require no energy input. These strategies can also help reduce peak load surges and total energy demand in extreme temperature events. This reduces the need for utility load shedding, which can put individuals at risk of hazardous heat or cold exposure. Our results may serve as a starting point for evidence-based public health guidelines on how individuals can sleep better during heat waves and cold snaps without relying on HVAC.
睡眠是人类健康和幸福的重要支柱。在高收入和中等收入国家，人们非常依赖供暖、通风和空调系统（HVAC）来控制卧室的内部热环境。然而，这些系统购买、维护和运行成本高昂，同时能源和环境密集型问题可能会因气候变化而增加。易于获取的被动和低能耗策略，如风扇和电加热毯，可以解决这些挑战，但它们在提供睡眠环境舒适度方面的相对有效性尚未得到研究。我们使用热模拟人进行了实验，结果表明，许多被动和低能耗策略在睡眠期间非常有效地补充或替代 HVAC 系统。与单独使用风扇相比，将被动策略与提高空气流动的低能耗策略（如天花板或基座风扇）结合使用，可将冷却效果提高三倍。我们将实验结果外推，以估计两个历史案例研究中的加热和冷却效果：2015 年巴基斯坦热浪和 2021 年德克萨斯州电力危机。被动和低能耗策略将睡眠时的热或冷暴露减少了 69-91%。我们测试的低能耗策略所需的能源比 HVAC 系统少一到两个数量级，而被动策略则不需要能源输入。这些策略还可以帮助减少极端温度事件中的峰值负荷浪涌和总能源需求。这减少了公用事业减载的需求，公用事业减载可能使个人面临危险的热或冷暴露风险。我们的结果可以为如何在不依赖 HVAC 的情况下在热浪和寒潮期间更好地睡眠的基于证据的公共卫生指南提供起点。
