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Weatherization or weatherproofing is the practice of protecting a building and its interior from the elements, particularly from sunlight, precipitation, and wind, and of modifying a building to reduce energy consumption and optimize energy efficiency.
Energy Star is a program run by the U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE) that promotes energy efficiency. The program provides information on the energy consumption of products and devices using different standardized methods. The Energy Star label is found on more than 75 different certified product categories, homes, commercial buildings, and industrial plants. In the United States, the Energy Star label is also shown on the Energy Guide appliance label of qualifying products.
Energy conservation is the effort to reduce wasteful energy consumption by using fewer energy services. This can be done by using energy more effectively or changing one's behavior to use less service. Energy conservation can be achieved through efficient energy use, which has some advantages, including a reduction in greenhouse gas emissions and a smaller carbon footprint, as well as cost, water, and energy savings.
Variable air volume (VAV) is a type of heating, ventilating, and/or air-conditioning (HVAC) system. Unlike constant air volume (CAV) systems, which supply a constant airflow at a variable temperature, VAV systems vary the airflow at a constant or varying temperature. The advantages of VAV systems over constant-volume systems include more precise temperature control, reduced compressor wear, lower energy consumption by system fans, less fan noise, and additional passive dehumidification.
Underfloor heating and cooling is a form of central heating and cooling that achieves indoor climate control for thermal comfort using hydronic or electrical heating elements embedded in a floor. Heating is achieved by conduction, radiation and convection. Use of underfloor heating dates back to the Neoglacial and Neolithic periods.
Energy recovery ventilation (ERV) is the energy recovery process in residential and commercial HVAC systems that exchanges the energy contained in normally exhausted air of a building or conditioned space, using it to treat (precondition) the incoming outdoor ventilation air. The specific equipment involved may be called an Energy Recovery Ventilator, also commonly referred to simply as an ERV.
An energy audit is an inspection survey and an analysis of energy flows for energy conservation in a building. It may include a process or system to reduce the amount of energy input into the system without negatively affecting the output. In commercial and industrial real estate, an energy audit is the first step in identifying opportunities to reduce energy expense and carbon footprint.
Efficient energy use, sometimes simply called energy efficiency, is the process of reducing the amount of energy required to provide products and services. For example, insulating a building allows it to use less heating and cooling energy to achieve and maintain a thermal comfort. Installing light-emitting diode bulbs, fluorescent lighting, or natural skylight windows reduces the amount of energy required to attain the same level of illumination compared to using traditional incandescent light bulbs. Improvements in energy efficiency are generally achieved by adopting a more efficient technology or production process or by application of commonly accepted methods to reduce energy losses.
Miscellaneous electric loads (MELs) in buildings are electric loads resulting from a multitude of devices (electronic and other) excluding main systems for space heating, cooling, water heating, or lighting. MELs are produced by hard-wired and “plug-in” electrical devices that draw power, including office equipment such as desktop computers and monitors, mobile electronics (laptops, tablets, mobile phones, and their charging units), printers, fans, task lighting, and home equipment such as home entertainment centers, kitchen electronics (microwaves, toaster ovens, cooking accessories), bath items (hair dryers, lighted mirrors, and electric hot tubs), and other devices such as security systems and ceiling fans. MELs are gaining greater importance in energy management as personal electronics proliferate and become standard across demographic groups. MELs demand has been rising as a percentage of total energy end-use and is expected to continue rising.
Voltage optimisation is a term given to the systematic controlled reduction in the voltages received by an energy consumer to reduce energy use, power demand and reactive power demand. While some voltage 'optimisation' devices have a fixed voltage adjustment, others electronically regulate the voltage automatically.
The United States is the second-largest single consumer of energy in the world. The U.S. Department of Energy categorizes national energy use in four broad sectors: transportation, residential, commercial, and industrial. Energy usage in transportation and residential sectors is largely controlled by individual domestic consumers. Commercial and industrial energy expenditures are determined by businesses entities and other facility managers. National energy policy has a significant effect on energy usage across all four sectors.
HVAC is a major sub discipline of mechanical engineering. The goal of HVAC design is to balance indoor environmental comfort with other factors such as installation cost, ease of maintenance, and energy efficiency. The discipline of HVAC includes a large number of specialized terms and acronyms, many of which are summarized in this glossary.
Underfloor air distribution (UFAD) is an air distribution strategy for providing ventilation and space conditioning in buildings as part of the design of a HVAC system. UFAD systems use an underfloor supply plenum located between the structural concrete slab and a raised floor system to supply conditioned air to supply outlets, located at or near floor level within the occupied space. Air returns from the room at ceiling level or the maximum allowable height above the occupied zone.
A dedicated outdoor air system (DOAS) is a type of heating, ventilation and air-conditioning (HVAC) system that consists of two parallel systems: a dedicated system for delivering outdoor air ventilation that handles both the latent and sensible loads of conditioning the ventilation air, and a parallel system to handle the loads generated by indoor/process sources and those that pass through the building enclosure.
ANSI/ASHRAE/IES Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings is an American National Standards Institute (ANSI) standard published by ASHRAE and jointly sponsored by the Illuminating Engineering Society (IES) that provides minimum requirements for energy efficient designs for buildings except for low-rise residential buildings. The original standard, ASHRAE 90, was published in 1975. There have been multiple editions to it since. In 1999 the ASHRAE Board of Directors voted to place the standard on continuous maintenance, based on rapid changes in energy technology and energy prices. This allows it to be updated multiple times in a year. The standard was renamed ASHRAE 90.1 in 2001. It has since been updated in 2004, 2007, 2010, 2013, 2016, and 2019 to reflect newer and more efficient technologies.
Variable refrigerant flow (VRF), also known as variable refrigerant volume (VRV), is an HVAC technology invented by Daikin Industries, Ltd. in 1982. Similar to ductless mini-split systems, VRFs use refrigerant as the primary cooling and heating medium, and is usually less complex than conventional chiller-based systems. This refrigerant is conditioned by one or more condensing units, and is circulated within the building to multiple indoor units. VRF systems, unlike conventional chiller-based systems, allow for varying degrees of cooling in more specific areas, may supply hot water in a heat recovery configuration without affecting efficiency, and switch to heating mode during winter without additional equipment, all of which may allow for reduced energy consumption. Also, air handlers and large ducts are not used which can reduce the height above a dropped ceiling as well as structural impact as VRF uses smaller penetrations for refrigerant pipes instead of ducts.
Radiant heating and cooling is a category of HVAC technologies that exchange heat by both convection and radiation with the environments they are designed to heat or cool. There are many subcategories of radiant heating and cooling, including: "radiant ceiling panels", "embedded surface systems", "thermally active building systems", and infrared heaters. According to some definitions, a technology is only included in this category if radiation comprises more than 50% of its heat exchange with the environment; therefore technologies such as radiators and chilled beams are usually not considered radiant heating or cooling. Within this category, it is practical to distinguish between high temperature radiant heating, and radiant heating or cooling with more moderate source temperatures. This article mainly addresses radiant heating and cooling with moderate source temperatures, used to heat or cool indoor environments. Moderate temperature radiant heating and cooling is usually composed of relatively large surfaces that are internally heated or cooled using hydronic or electrical sources. For high temperature indoor or outdoor radiant heating, see: Infrared heater. For snow melt applications see: Snowmelt system.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers is an American professional association seeking to advance heating, ventilation, air conditioning and refrigeration (HVAC&R) systems design and construction. ASHRAE has over 50,000 members in more than 130 countries worldwide.
Cooling load is the rate at which sensible and latent heat must be removed from the space to maintain a constant space dry-bulb air temperature and humidity. Sensible heat into the space causes its air temperature to rise while latent heat is associated with the rise of the moisture content in the space. The building design, internal equipment, occupants, and outdoor weather conditions may affect the cooling load in a building using different heat transfer mechanisms. The SI units are watts.
References
- 1 2 Nordman, Bruce; Marla McWhinney (2006). "Electronics Come of Age: A Taxonomy for Miscellaneous and Low Power Products". ACEEE Summer Study on Energy Efficiency in Buildings. Washington, D.C.: ACEEE.
- ↑ ASHRAE (2010). ANSI/ASHRAE Standard 90.1-2010: Energy Standard for Buildings Except Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers.
- ↑ U.S. Green Building Council (October 2007). LEED for New Construction & Major Renovation Version 2.2 Reference Guide (Third ed.). U.S. Green Building Council. ISBN 978-1-932444-11-7.
- ↑ COMNET (2010). Commercial Buildings Energy Modeling Guidelines and Procedures. Oceanside, CA: Commercial Energy Services Network.
- ↑ Energy Information Administration (1999), Annual Energy Outlook 2000 with Projections to 2020, U.S. Department of Energy
- ↑ "Commercial Buildings Energy Consumption Survey". U.S. Energy Information Administration. Retrieved 28 November 2011.
- ↑ Hosni, M. H.; Beck, B. T. (2009), Update to Measurements of Office Equipment Heat Gain Data, Final Report, ASHRAE Research Project RP-148
- ↑ Wilkins, Christopher K.; Mohammad H. Hosni (2011). "Plug Load Design Factors". ASHRAE Journal. 53 (5): 30–34.
- ↑ Webber, C. A.; R. E. Brown; J. Koomey (2000). "Savings Estimates for the ENERGY STAR® Voluntary Labeling Program". Energy Policy. 28 (15): 1137–49. doi:10.1016/s0301-4215(00)00083-5. S2CID 150599301.
- ↑ Webber, C. a. (2001). "Field Surveys of Office Equipment Operating Patterns". Draft Report, LBNL-46930.
{{cite journal}}: Cite journal requires|journal=(help) - ↑ Webber, C. a. (2006). "After-Hours Power Status of Office Equipment in the USA" (PDF). Energy. 31 (14): 2823–38. doi:10.1016/j.energy.2005.11.007. S2CID 55695969.