NOVEL INTEGRATED DESIGN STRATEGIES FOR NET-ZERO-ENERGY SOLAR BUILDINGS(NZESBS)IN NANJING,CHINA

The connotations and denotations of the term net-zero-energy solar buildings(NZESBs)have been in constant flux because of continuous developments in solar heating technology,solar photovoltaic(PV)technology,building energy-storage technology,regional energy-storage technology,and energy-management systems.This paper focuses on innovative strategies for implementing NZESBs in Nanjing,China.These strategies include integrated architectural design,including passive solar design(respecting climatic characteristics and conducting integrated planning based on the environment,building orientation,distance between buildings,build-ing shape,ratio of window area to wall area,and building envelope)and active solar design(integration of the solar-energy-collecting end of the system–collectors and PV panels–with the building surface–roof,wall surfaces,balconies,and sun-shading devices–and the integration of solar-energy transfer and storage equip-ment with the building).Some Nanjing-specific recommendations and findings on NZESBs are proposed.The results illustrate that NZESBs can be realized in Nanjing if solar energy technologies are appropriately integrated with the character-istics of Nanjing’s geography,climate and buildings.

Research on Key Technologies of Solar Photovoltaic Building Integration

On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power and biomass power generation in China ranked first in the world[1].Solar photovoltaic power generation is the most important development direction of clean energy in the world.It is an important energy strategy to combine it with the field of construction in China.This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration,and explores its future development direction and ways,in order to constantly promote the industrialization of new energy technology in China.

Integrated Building Envelope Design Process Combining Parametric Modelling and Multi-Objective Optimization

As an important element in sustainable building design, the building envelope has been witnessing a constant shift in the design approach. Integrating multi-objective optimization (MOO) into the building envelope design process is very promising, but not easy to realize in an actual project due to several factors, including the complexity of optimization model construction, lack of a dynamic-visualization capacity in the simulation tools and consideration of how to match the optimization with the actual design process. To overcome these difficulties, this study constructed an integrated building envelope design process (IBEDP) based on parametric modelling, which was implemented using Grasshopper platform and interfaces to control the simulation software and optimization algorithm. A railway station was selected as a case study for applying the proposed IBEDP, which also utilized a grid-based variable design approach to achieve flexible optimum fenestrations. To facilitate the stepwise design process, a novel strategy was proposed with a two-step optimization, which optimized various categories of variables separately. Compared with a one-step optimization, though the proposed strategy performed poorly in the diversity of solutions, the quantitative assessment of the qualities of Pareto-optimum solution sets illustrates that it is superior. © 2016, Tianjin University and Springer-Verlag Berlin Heidelberg.

A SURVEY OF SOLAR ENVELOPE PROPERTIES USING SOLID MODELLING

Solar envelope is a concept for regulating solar access in urban planning.It is a roof-like imaginary surface over a given piece of land that controls the maximum allowed building height in order to avoid casting shadows on the neighbours during a specific period.The volume of solar envelopes regulates building density,depending on geo-metric attributes and time(plot size and proportions,orientation,ground slope,latitude,duration of insolation).This work compares the effect of such factors on the size of solar envelopes on a variety of land parcels,individually or in groups.Repeated applications of solid modelling are used to calculate in each case the values of‘Solar Volume Coefficient’,i.e.the volume of a solar envelope per unit of its base as a measure for comparisons.Results show the influence of the various factors affecting the geometry of solar envelopes.Among other findings,it is also shown that solar envelopes gener-ate urban densities lower than conventional urban regulations.The total volume of solar envelopes over an area(‘Solar Building Potential’)can be increased by raising the reference level of solar envelopes(‘shadow fence’or‘solar fence’).Lower urban densities are compensated by facilitating solar applications,as well as by enhancing daylight,ventilation,and vistas in the urban context,thus creating new‘solar cityscapes’exem-plified here on existing street patterns.