随着房屋隔热性能的提高和高效炉子的普及，水加热能源的使用可能会超过空间加热能源的使用。尽管热水器的效率正在提高，但将热水输送至终端用途的热水分配系统对能源的影响还没有得到充分的研究。本文报告了一项实地研究的初步结果，该研究旨在评估加利福尼亚州20户家庭室内热水分配系统造成的水和能源浪费。监控系统由一组无线仪表组成，用于测量终端使用点和热水器处的室内热水和冷水的温度和流量。 无线传感器网络由连接到无线微尘的流量计组成，将数据传输到中央“管理器”微尘，后者将信息发送到嵌入式计算机。嵌入式计算机运行软件，通过互联网将收集的数据发送到服务器进行存档。每当水流动时，温度和流量数据都会以1秒的间隔收集。这种详细程度的数据提供了辨别管道中剩余热水量的能力，因为之前的热水在使用前已经冷却。通过检查从淋浴喷头流出的水的流速和温度，可以测量用户等待热水到达时浪费的水量（和能量）。 过去的研究估计淋浴时的垃圾量超过25%。本文报告了一个项目，通过直接现场测量更新这些估计值。将介绍为高性能和可持续建筑设计热水分配系统的考虑因素。引文:ASHRAE论文CD:2014 ASHRAE年会，华盛顿州西雅图

As houses become better insulated and more efficient furnaces become widespread, water heating energy use can exceed space heating energy use. Although water heater efficiency is improving, the energy impacts of the hot water distribution system delivering the hot water to end uses have been inadequately studied. This paper reports on the initial findings of a field study to evaluate the waste of water and energy in indoor water use in 20 California homes attributable to on-premise hot water distribution systems. The monitoring systems consist of a collection of wireless meters to measure the temperature and flow rates of indoor water use, both hot and cold, at the end use points and at the water heater. The wireless sensor network consists of flow meters connected to wireless motes transmitting data to a central "manager" mote, which sends the information to an embedded computer. The embedded computer is running software to send the collected data through the internet to a server for archiving. The temperature and flow rate data are collected at one second intervals whenever water is flowing.Data at this level of detail provides the ability to discern how much the hot water remaining in pipes since the previous hot water draw has cooled off before it is used. By examining flow rates and temperatures of the water coming out of showerheads, it is possible to measure amount of water (and energy) wasted while the user waits for hot water to arrive.Past studies have estimated the waste at showers to be greater than 25%. This paper reports on a project to update those estimates with direct field measurements. Considerations for designing hot water distribution systems for high performance and sustainable buildings will be presented.