Abstract"Net Zero Energy Building" has become a prominent wording to describe the synergy of energy efficient building and renewable energy utilization to reach a balanced energy budget over a yearly cycle. Taking into account the energy exchange with a grid infrastructure overcomes the limitations of seasonal energy storage on-site. Even though the wording "Net Zero Energy Building" focuses on the annual energy balance, large differences may occur between solution sets in the amount of grid interaction needed to reach the goal. The paper reports on the analysis of example buildings concerning the load matching and grid interaction. Indices to describe both issues are proposed and foreseen as part of a harmonized definition framework. The work is part of subtask A of the IEA

A major advantage of the Net Zero Energy Building (Net ZEB) approach is claimed to be the absence of energy performance indicators, hence avoiding the need to set internationally agreed limits. Nevertheless, if the rationale is to endorse the design of environmentally friendly buildings that promote sustainable development, then reasonably strict requirements on energy efficiency should be satisfied while providing high levels of indoor environmental quality and consequent users comfort. Otherwise, the risk is that poorly designed buildings could achieve the definition of Net ZEB simply by means of oversized generation systems. The purpose of this paper is to provide an overview of existing international standards and/or design best practices based on comfort and energy efficiency requirements that can be taken as general recommendations for the design of Net ZEBs.

Energy efficiency in buildings undeniably plays a vital role in addressing climate change. At the level of building planning, a thorough analysis with thermal dynamic calculations can be carried out to assess energy demand and resulting CO2 emissions of buildings due to the high level of detail usually provided at this stage. In urban planning design on the other hand, energy and resource-related parameters are usually not quantified, as at this stage of the planning process other urban planning factors predominate the concepts. However, numerous aspects that are determined at the stage of urban planning cannot be changed anymore later on in the process even though, they can have a significant impact on the energy demand. This includes the structuring of the building blocks, density and height of the buildings, orientation and inclination of the surfaces as well as greening of the outer shell and availability of direct solar radiation. This paper describes the analysis of parameters, which have a significant influence on energy and resource consumption of urban developments. This includes new developments as well as the existing building stock in order to provide quantifiable indicators for refurbishment and densification measures. The simulation tool CityCalc, which has been developed in a previous research project provides the environment for the analysis. To validate the approach, the identified parameters are analysed in an exemplary case study for a Viennese urban development area. The results aim at identifying and quantifying the key influencing parameters of urban planning design on the energy and resource efficiency of new and existing urban development areas in order to gain essential insights for the integration of climate-relevant factors for future planning processes.

No abstract

No abstract