As concerns over energy and global warming increase well into the 21st century, many are seeking ways to continually increase energy efficiency and reduce energy consumption. Commercial and residential buildings alone account for 40% of primary energy consumption and 70% of electricity usage. The demand for energy by the commercial sector is projected to increase by 1.2% per year from 2006 to 2030, driven by trends in population and economic growth. In order to reduce the energy consumption of the commercial building sector, the Department of Energy (DOE) has established the Commercial Building Initiative, a goal to create technologies and design approaches that lead to marketable zero-energy commercial buildings (ZEB) by 2025. This goal is evident in Section 422 of the Energy Independence and Security Act of 2007, which calls for the increased production of clean renewable fuels and increased efficiency of products, buildings, and vehicles. Today, more and more building owners are looking to have their existing or new building be “green”, a term ubiquitous with clean energy and environmental friendliness. Whether driven by financial or environmental reasons, the green movement is driving building designers and engineers to develop ever more inventive methods to conserve energy in buildings. New materials, techniques, technologies, and computer modeling programs have helped energy efficient buildings come to life.
A net ZEB is, ideally, a building that through high efficiency gains can meet the rest of its energy needs through renewable technologies. Zero is the point at which the building no longer consumes energy but rather produces it. At the zero point, the sum of the energy flows in equal the sum of the energy flows out.
A zero-energy building (ZEB) produces enough renewable energy to meet its own annual energy consumption requirements, thereby reducing the use of non-renewable energy in the building sector. ZEBs use all cost-effective measures to reduce energy usage through energy efficiency and include renewable energy systems that produce enough energy to meet remaining energy needs. There are several long-term advantages of moving toward ZEBs, including lower environmental impacts, lower operating and maintenance costs, better resiliency to power outages and natural disasters, and improved energy security. Reducing building energy consumption in new building construction or renovation can be accomplished through various means, including integrated design, energy efficiency retrofits, reduced plug loads and energy conservation programs. Reduced energy consumption makes it simpler and less expensive to meet the building’s energy needs with renewable sources of energy. ZEBs have a tremendous potential to transform the way buildings use energy and there are an increasing number of building owners who want to meet this target.
There are passive and active design approaches that can reduce energy consumption. Active energy efficiency improvements are using or producing energy, and they are an active part of the systems in the building. Active strategies usually consist of heating and cooling systems, while passive design measures include building orientation, air sealing, continuous insulation, windows and daylighting, and designing a building to take advantage of natural ventilation opportunities. As you can see below, there are some design approaches that include active and passive strategy. If you want to read more about these strategy, please click on button below of them.
Solar/Photovoltaic Panels
Thermal Insulation
Energy Storage
Natural Ventilation
Rainwater Harvesting
