**Abstract**

The Net Zero Energy Building is generally described as an extremely energyefficient building in which the residual electricity demand is provided by renewable energy. Solar power is also regarded to be the most readily available and usable form of renewable electricity produced at the building site. In contrast, energy conservation is viewed as an influential national for achieving a building's net zero energy status. This chapter aims to show the value of the synergy between energy conservation and solar energy transfer to NZEBs at the global and regional levels. To achieve these goals, both energy demand building and the potential supply of solar energy in buildings have been forecasted in various regions, climatic conditions, and types of buildings. Building energy consumption was evaluated based on a bottom-up energy model developed by 3CSEP and data inputs from the Bottom-Up Energy Analysis System (BUENAS) model under two scenarios of differing degrees of energy efficiency intention. The study results indicate that the acquisition of sustainable energy consumption is critical for solar-powered net zero energy buildings in various building styles and environments. The chapter calls for the value of government measures that incorporate energy conservation and renewable energy.

**Keywords:** net zero-energy building, electricity demand, renewable electricity, bottom-up energy analysis, solar energy

### **1. Introduction**

The general description of a net zero energy building that can be found in the documentation is: "Net Zero Energy Building (NZEB) is a residential or industrial building with substantially decreased energy needs by productivity improvements, so that the balance of power requirements can be provided by sustainable technology." Even so, the researchers note that the "absolute zero energy structure" can be described in many forms, both on the parameter and the standard [1]. This description showed that energy conservation would be one of the techniques to achieve a net zero energy building output. The need for energy efficiency methods in NZEBs was already highlighted in several research sources. For example references of [2]. Focus were put on the preference for power conservation in the development of the NZEB and established the principle: 'first take up demand, then supply,' which implies that, in attempt to reach a net zero energy balance in buildings, it is important, first, to reduce power usage and power losses by energy conservation steps, lighting, ventilation, passive solar energy, high-efficiency appliances, thermal comfort, passive cooling, etc., instead and then using green electricity options to fulfill the energy requirements of buildings. Energy efficiency usually provides

cost effective solutions for lowering electricity demand that significantly reduces the scale and thus the expense of the clean energy systems required and associated distributed technology [3].

This chapter aims to analyze synergy among power efficiency and on-site solar energy supply to move toward certain net zero energy quality. The results are taken based on the creation of the Building Integrated Solar Power System and the evidence from two other well-known field researches. The purpose of this study is to demonstrate that energy conservation and sustainable energy production are inseparable solutions and that the inadequacy of each of them has an enraging effect on the ability to reach a net zero energy target.
