在减少建筑所需能源和温室气体排放的国际行动框架内，国际能源机构最近制定了一项新任务，以研究净零能源建筑（NZEB）。NZEB的共同概念是一座建筑，其年能耗平衡趋于零。这一概念仍然太不精确，本文作者参与了IEA Task40子任务B的活动，目的是建立对NZEB的国际共识。该任务基于一种通用方法，用于确定和完善设计方法和工具，以支持行业采用NZEB的创新需求/供应技术。这一目标是通过对特定NZEB案例研究的详细建模和分析来实现的。 在子任务B的具体目标中，可以包括对重新设计的研究的分析。重新设计的研究应该为植物、建筑围护结构或对环境的影响找到更好的替代解决方案，从而显著改变建筑。为了提供有关NZEB设计过程的高质量信息，决定详细研究位于意大利安科纳的叶屋（LH）的具体案例研究。研究建筑在热环境、能源生产和消耗、用水和占用方面受到全面监控。本文的目的是通过使用收集的数据和分析厂房建筑群的详细TRNSYS模型，提出一些改善所选建筑性能的方案。该模型允许对设计中的一些变化的影响进行详细评估，这些变化可以在能源消耗和建筑环境影响方面改善叶屋的性能。 执行的分析表明，建筑围护结构在热性能方面已经非常有效，而热电厂和光伏系统的重新设计应允许达到接近净零的能量性能。引用:ASHRAE会议论文，蒙特利尔，QC

In the framework of international actions to reduce the energy requirements and greenhouse gases emissions due to buildings, a new International Energy Agency task has been recently established in order to study Net Zero Energy Buildings (NZEBs). The commonly shared concept of NZEB, is a building whose annual balance of energy consumptions tends to zero. This concept is still too imprecise and the authors of this paper participate to the activities of SubTask B of IEA Task40 with the aim of establishing an internationally agreed understanding on NZEBs. The task is based on a common methodology for identifying and refining design approaches and tools to support industry adoption of innovative demand/supply technologies for NZEBS. This goal is pursued through detailed modeling and analysis of specific NZEB case studies. Among the specific objectives of the Sub Task B it is possible to include the analysis of redesigned studies. Redesigned studies should identify better alternative solutions for plants, building envelope or impact on the environment that significantly modify the building. To provide high quality information about the design process of a NZEB, it was decided to examine in detail the specific case study of the Leaf House (LH) located in Ancona, Italy. The studied building is fully monitored in terms of thermal environment, energy production and consumption, water use and occupancy. The purpose of this paper is to present some optionsto improve the performance of the selected building, identified by using the collected data and analyzing a detailed TRNSYS model of plant-building complex. The model has allowed detailed evaluation of the effects of some changes in the design that can improve the behavior of the Leaf House in terms of consumptions of energy resources and environmental impact of the building. The performed analysis shows that the building envelope is already very effective in terms of thermal performance, while the redesign of the thermal plants and the PV system should permit to reach a nearly net zero energy performance.