Browsing by Subject "energy efficiency"

Now showing 1 - 4 of 4
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    A Method for Measuring the Efficiency Gap between Average and Best Practice Energy Use: The ENERGY STAR Industrial Energy Performance Indicator
    (2005) Boyd, GA
    A common feature distinguishing between parametric/statistical models and engineering economics models is that engineering models explicitly represent best practice technologies, whereas parametric/statistical models are typically based on average practice. Measures of energy intensity based on average practice are of little use in corporate management of energy use or for public policy goal setting. In the context of companyor plant-level indicators, it is more useful to have a measure of energy intensity that is capable of indicating where a company or plant lies within a distribution of performance. In other words, is the performance close to (or far from) the industry best practice? This article presents a parametric/statistical approach that can be used to measure best practice, thereby providing a measure of the difference, or "efficiency gap," at a plant, company, or overall industry level. The approach requires plant-level data and applies a stochastic frontier regression analysis used by the ENERGY STARTM industrial energy performance indicator (EPI) to energy intensity. Stochastic frontier regression analysis separates energy intensity into three components: systematic effects, inefficiency, and statistical (random) error. The article outlines the method and gives examples of EPI analysis conducted for two industries, breweries and motor vehicle assembly. In the EPI developed with the stochastic frontier regression for the auto industry, the industry median "efficiency gap" was around 27%.
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    Artificial intelligence evolution in smart buildings for energy efficiency
    (Applied Sciences (Switzerland), 2021-01-02) Farzaneh, H; Malehmirchegini, L; Bejan, A; Afolabi, T; Mulumba, A; Daka, PP
    © 2021 by the authors. Licensee MDPI, Basel, Switzerland. The emerging concept of smart buildings, which requires the incorporation of sensors and big data (BD) and utilizes artificial intelligence (AI), promises to usher in a new age of urban energy efficiency. By using AI technologies in smart buildings, energy consumption can be reduced through better control, improved reliability, and automation. This paper is an in‐depth review of recent studies on the application of artificial intelligence (AI) technologies in smart buildings through the concept of a building management system (BMS) and demand response programs (DRPs). In addition to elaborating on the principles and applications of the AI‐based modeling approaches widely used in building energy use prediction, an evaluation framework is introduced and used for assessing the recent research conducted in this field and across the major AI domains, including energy, comfort, design, and maintenance. Finally, the paper includes a discussion on the open challenges and future directions of research on the application of AI in smart buildings.
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    Environmental and Technology Policy Options in the Electricity Sector: Interactions and Outcomes
    (2014-04-14) Fischer, Carolyn; Newell, Richard G; Preonas, Louis
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    Modeling Energy Efficiency as a Supply Resource
    (2017-08-22) Gumerman, Etan; Vegh, Tibor
    Energy efficiency may be an inexpensive way to meet future demand and reduce greenhouse gas emissions, yet little work has been attempted to estimate annual energy efficiency supply functions for electricity planning. The main advantage of using a supply function is that energy efficiency adoption can change as demand changes. Models such as Duke University’s Dynamic Integrated Economy/Energy/Emissions Model (DIEM) have had to rely on simplistic or fixed estimates of future energy efficiency from the literature rather than on estimates from energy efficiency supply curves. This paper attempts to develop a realistic energy efficiency supply curve and to improve on the current energy efficiency modeling. It suggests an alternative approach based on saved-energy cost data from program administrators and explains the methodologies employed to create the supply curve. It illustrates this approach with results from DIEM for various electricity demand scenarios. The analysis suggests that an additional 5%–9% of energy efficiency is deployed for every 10% increase in the cost of electricity. Therefore, DIEM “invested” in energy efficiency up to an inelastic point on the energy efficiency supply curve. By contrast, the U.S. Environmental Protection Agency’s energy efficiency approach assumes that realized energy efficiency is fixed, and has no elasticity, regardless of changes to marginal costs or constraints that affect emissions or economics.