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At least 19 records

Walmart - Saving Energy, Saving Money Through Comprehensive Retrofits, Commercial Building Energy Efficiency (Fact Sheet); Energy Efficiency & Renewable Energy (EERE)

Walmart partnered with the U.S. Department of Energy (DOE) in 2009 to develop and demonstrate energy retrofits for existing buildings. The goal was to reduce energy consumption by at least 30% versus ASHRAE Standard 90.1-2007, as part of DOE's Commercial Building Partnerships (CBP) Program. The project presented here, the retrofit of a 213,000 square foot store in Centennial, Colorado, withefficiency measures across multiple building systems, is part of Walmart's ongoing environmental sustainability program, which originated in 2005.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Saving Energy, Saving Money [Slides]

Make sure you have CO detectors installed; Test batteries regularly; Have your furnace serviced annually; Don’t use grills or generators indoors.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

A framework for quantifying the impact of occupant behavior on energy savings of energy conservation measures

To improve energy efficiency—during new buildings design or during a building retrofit—evaluating the energy savings potential of energy conservation measures (ECMs) is a critical task. In building retrofits, occupant behavior significantly impacts building energy use and is a leading factor in uncertainty when determining the effectiveness of retrofit ECMs. Current simulation-based assessment methods simplify the representation of occupant behavior by using a standard or representative set of static and homogeneous assumptions ignoring the dynamics, stochastics, and diversity of occupant's energy-related behavior in buildings. The simplification contributes to significant gaps between the simulated and measured actual energy performance of buildings. This paper presents a framework for quantifying the impact of occupant behaviors on ECM energy savings using building performance simulation. During the first step of the study, three occupant behavior styles (austerity, normal, and wasteful) were defined to represent different levels of energy consciousness of occupants regarding their interactions with building energy systems (HVAC, windows, lights and plug-in equipment). Next, a simulation workflow was introduced to determine a range of the ECM energy savings. Then, guidance was provided to interpret the range of ECM savings to support ECM decision making. Finally, a pilot study was performed in a real building to demonstrate the application of the framework. Simulation results show that the impact of occupant behaviors on ECM savings vary with the type of ECM. Occupant behavior minimally affects energy savings for ECMs that are technology-driven (the relative savings differ by less than 2%) and have little interaction with the occupants; for ECMs with strong occupant interaction, such as the use of zonal control variable refrigerant flow system and natural ventilation, energy savings are significantly affected by occupant behavior (the relative savings differ by up to 20%). Finally, the study framework provides a novel, holistic approach to assessing the uncertainty of ECM energy savings related to occupant behavior, enabling stakeholders to understand and assess the risk of adopting energy efficiency technologies for new and existing buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

How To Determine and Verify Operations and Maintenance Savings in Energy Savings Performance Contracts

Operations and maintenance (O&M) savings frequently occur in energy savings performance contracts (ESPCs). During FY 2022, 37% of reported annual cost savings for projects awarded under the U.S. Department of Energy (DOE) ESPC indefinite delivery indefinite quantity (IDIQ) contracts and in the performance period were due to O&M or other energy- and/or water-related cost savings, with the balance (63%) from utility cost savings (i.e., energy or water cost savings). Sometimes the energy- and water-related cost savings are acknowledged and included in payments within ESPCs; other times, for various reasons, they are not. As presented in this guide, FEMP recommends including energy- and water-related cost savings that are O&M (including related repair and replacement) savings in the financial aspects of an ESPC, to the extent such savings can be documented. Inclusion of these savings will help augment project scopes and/or lower interest costs (by shortening financing terms). However, there is a burden of proof as to what constitutes acceptability in O&M savings that needs to be carefully considered and documented in individual projects. Beyond promoting a key tenet used in U.S. federal performance contracting—that savings must be from actual budgets and therefore based on the level of O&M that is actually occurring, not what should have been performed—FEMP also recommends good practice in establishing and documenting O&M baselines, formulating the rationale for baseline adjustments during the performance period, and conducting ongoing verification activities. This document concludes with five examples of how O&M savings may be handled, in situations ranging from the partial displacement of O&M contracts to consolidation and “virtualization” of servers in data centers. A key theme that permeates this guide is the importance of thoroughly documenting all conditions and assumptions used in the development of and accounting for O&M costs and savings throughout the ESPC life cycle, from baseline-setting to measurement and verification (M&V) of the savings during each year of the performance period. Doing so not only prevents internal claims of non-performance (especially in the case of staff turnover during the contract term), but also simplifies ordering agency and energy service company (ESCO) response in the event of scrutiny from oversight organizations, such as government audits. While this guide focuses on federal ESPCs, it may also be applicable when O&M savings are included in utility energy service contracts (UESCs) and non-federal ESPCs.

Voss, Phil↗

Columbia, Missouri: Using Energy Data to Reduce Emissions and Achieve Low-Income Household Energy Savings (City Energy: From Data to Decisions)

This fact sheet "Columbia, Missouri: Using Energy Data to Reduce Emissions and Achieve Low-Income Household Energy Savings" explains how the City of Columbia used data from the U.S. Department of Energy's Cities Leading through Energy Analysis and Planning (Cities-LEAP) and the State and Local Energy Data (SLED) programs to inform its city energy planning. It is one of ten fact sheets in the "City Energy: From Data to Decisions" series.

Cities leading through energy analysis and plannin↗

New Haven, Connecticut: Targeting Low-Income Household Energy Savings (City Energy: From Data to Decisions)

This fact sheet "New Haven, Connecticut: Targeting Low-Income Household Energy Savings" explains how the City of New Haven used data from the U.S. Department of Energy's Cities Leading through Energy Analysis and Planning (Cities-LEAP) and the State and Local Energy Data (SLED) programs to inform its city energy planning. It is one of ten fact sheets in the "City Energy: From Data to Decisions" series.

Cities leading through energy analysis and plannin↗

Quantifying adoption rates and energy savings over time for advanced energy-efficient manufacturing technologies

Energy-efficient manufacturing technologies can reduce energy consumption and lower operating costs for manufacturing facilities, but up-front costs and increased process complexity frequently lead to manufacturers being reluctant to adopt such technologies. To avoid overestimating the benefits of advanced energy-efficient manufacturing technologies, it is necessary to account for how quickly and how widely the technology will be adopted by manufacturers. This work develops a method for estimating manufacturing technology adoption rates using quantitative technology characteristics including energetic, economic, and technical criteria that capture both incentives (such as energy and cost savings) and disincentives (such as increased process complexity) for technology adoption. This method is unique in that it can be applied before or after a technology reaches the market; other adoption rate estimation methods require sales data and can only be applied post-market. Eleven technology characteristics are considered, with each characteristic weighted to reflect its impact on the overall technology adoption rate. Technology characteristic data is used to estimate model parameters for the Bass diffusion curve, which quantifies the change in the number of new technology adopters in a population over time. Finally, energy savings at the sector level are calculated over time by multiplying the number of new technology adopters at each time step with the technology’s facility-level energy savings. The proposed method is demonstrated with an application to glass industry manufacturing technologies using technology data obtained from the U.S. Department of Energy's 2017 bandwidth study. The potential energy savings for each technology and the rate at which each technology is adopted in the sector are quantified and used to identify the technologies which offer the greatest cumulative sector-level energy savings over a period of 20 years.

advanced manufacturing↗

Energy Saving Analysis Using Energy Intensity Usage and Specific Energy Consumption Methods

This study presents the energy saving analysis reached through employing the energy intensity usage and specific energy consumption method. The energy analyses conducted in this study are used for implementing a new technology. However, they are additionally used to evaluate the latest concepts, techniques, processes, and uses for technologies, which are aimed at improvement of energy savings. This study shows the correlation between energy consumption, potential energy savings, and the impact of the energy assessment in different industrial sectors. The correlation is found by using two indicators: (1) the energy intensity usage (EIU) and (2) the specific energy consumption (SEC). The data analysis in this study considers the assessments for 67 industries from 2015 to 2019 and classifies those assessments using the Standard Industrial Classification (SIC) code. The results show that energy savings and energy consumption are linearly related. Also, the energy assessment improves energy performance in a more significant way for smaller companies than for larger industries. Furthermore, these results can be extrapolated by identifying the potential benefits of the energy management system (EMS) implementation.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Accelerating the Uptake of ISO 50001 in Commercial Buildings: Two Early Adopters Utilizing an “Enterprise-wide” Approach to Save Energy and Beyond

ISO 50001:2011 is a voluntary international standard that provides a flexible framework for implementing a continual improvement-based system to manage energy. Experience shows that institutionalizing ISO 50001’s proven best practices can lead to deep total energy savings of 5–20 percent annually. Based on an internationally developed methodology for predicting future impacts of ISO 50001 uptake within a region from McKane et al. (2017), we estimate that adopting ISO 50001 within the U.S. commercial buildings sector can generate annual energy savings of approximately 65 billion Btu in 2030. Commercial properties also could leverage ISO 50001 to unlock benefits through increased property values, rental premiums, company valuations, and access to new capital markets. Currently, within the United States, ISO 50001 has been primarily adopted in the industrial sector, with limited uptake in the commercial sector. This paper discusses the motivation, implementation approach, and achieved benefits of two ISO 50001-certified companies with commercial building portfolios in the United States. Anecdotal results from these companies show that the commercial buildings sector has an opportunity to implement ISO 50001 cost-effectively at the enterprise level and scale energy savings quickly—especially among organizations with campuses and/or chains of geographically scattered buildings with similar building energy systems. These early results, coupled with estimated impacts from ISO 50001 uptake within the U.S. commercial buildings sector, suggest that direct uptake and incorporation of the standard in utility and government programs will generate significant energy and greenhouse gas reductions.

Liu, Jingjing↗

Measurement of Exterior Foundation Insulation to Assess Durability in Energy-Saving Performance

The foundation of a house is a sometimes ignored component of the building because of its low visibility. It is increasingly evident, however, that attention to good foundation design and construction significantly benefits the homeowner and the builder by mitigating future problems. Good foundation design and construction practice involves not only insulating to save energy but also providing effective structural design as well as moisture, termite, and radon control techniques as appropriate. Energy efficiency in housing is augmented by use of exterior slab and basement insulation, but high moisture content in the insulation material has led to concerns about its durability. The activity under this task was to extract six different exterior insulation systems that were characterized at installation and have been in the ground for 9 months to 15 years. R-value and moisture content were measured and inspections conducted for evidence of termite intrusion or deterioration. Based on the results, the durability of the various systems has been documented and assessments made of which systems appear to be best practice. Heat flux and temperature measurement data had been archived for some of the exterior insulation tests, thereby providing a unique opportunity to assess energy-saving performance and durability over the long term. The results show that the durability of foundation insulation systems depends on insulation type as well as on foundation type and local boundary conditions, the latter of which may have a marked influence on the durability of energy-saving performance.

Kehrer, Manfred↗

ePROJECT BUILDER: PROMOTING WIDER ADOPTION OF ENERGY SAVINGS PERFORMANCE CONTRACTS THROUGH STANDARDIZATION AND TRANSPARENCY

The United States Federal Government has been conducting guaranteed savings energy savings performance contracts for over 20 years and now relies on ESPC for the majority of its energy efficiency work. Along with a related financed project type, these deals resulted in $4.2 billion of project investment in the five years ending in 2016, a pace that has even accelerated since. Measurement and verification (M&V) on the projects is the key to assuring savings realization and persistence. Perceived as a weakness or burdensome added cost in the early years of the program, M&V has become a strength. All energy conservation measures (ECMs) have some form of measurement – defined as a measured baseline establishment followed by at least one measurement of the main energy-saving parameter taken in the performance period for each ECM. The government’s in-house energy consulting office, the Federal Energy Management Program (FEMP), now recommends measurement of these “Option A” M&V ECMs throughout the contract term, usually annually. Moreover, a significantly higher percentage of projects are now characterized by more ambitious M&V, including Option B (all parameter measurement) for most generation (including renewable) and some efficiency measures, and more frequent Option C (whole facility utility bill analysis) for “deep retrofit” projects with multiple, interactive ECMs. Coincident with this progress in M&V has been a much greater embracing of ESPC by the federal agencies, resulting in the enormous rate of projects now executed. This paper traces the evolution of M&V in federal ESPC and argues that the heightened credibility of the savings has contributed significantly to the procurement vehicle’s long-term viability. This focus on savings integrity via M&V has been learned over two decades for U.S. federal ESPC, but countries with developing ESPC markets would be wise to emphasize it as their markets emerge, allowing them to avoid some of the “growing pains” experienced in the U.S.

Earni, Shankar↗

Achieving Deeper Energy Savings in Federal Energy Performance Contracts

Legislation requires each agency of the US federal government to reduce the aggregate energy use index of its buildings by 30% by 2015, with respect to a 2003 baseline. The declining availability of appropriated funding means that energy performance contracting will be key to achieving this goal. Historically however, energy performance contracts have been able to reduce energy use by only about 20% over baseline. Achieving 30% energy reductions using performance contracting will require new approaches and a specific focus on achieving higher energy savings, both by ESCOs and by agencies. This paper describes some of the ways federal agencies are meeting this challenge, and presents results from the efforts of one agency the US General Services Administration -- to achieve deeper energy savings in conventional energy savings performance contracts.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Benefits assessment of cool skin and ventilated cavity skin: Saving energy and mitigating heat and grid stress

This study assessed the energy-saving and climate-adaptive potential of cool skin and ventilated cavity skin facade technologies in Seoul's high-rise apartment buildings. We created weather scenarios for historical, mid-term future, and long-term future conditions using Coordinated Regional Downscaling EXperiment (CORDEX) method. Building energy simulations were conducted on a South Korean high-rise apartment model to evaluate their performance under different weather conditions. The results indicate that cool skin and ventilated cavity skin technologies can save cooling energy during summers but lead to heating energy penalties in winters. Ventilated cavity skin outperforms cool skin, offering better cooling energy savings and reduced heating penalties. Combining both technologies yields the highest overall energy savings, with 7 %, 9 %, and 10 % cooling energy savings for cool skin, ventilated cavity skin, and the combined package, respectively. However, cool skin increases heating energy consumption by 5 %, while ventilated cavity skin has minimal impact on heating energy. These envelope technologies also reduce peak electricity demand by at least 5 %, 8 %, and 9 %, respectively. They contribute to heat stress reduction, enhance resilience, and decrease extreme heat risks for occupants during power outages by at least 18 % under various weather conditions. Considering the prevalence of aging high-rise apartments in South Korea, adopting these envelope renovation strategies can effectively reduce cooling loads, enhance thermal comfort, and boost resilience under future climates, while avoiding costly reconstruction.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Prevalence of typical operational problems and energy savings opportunities in U.S. commercial buildings

In the United States, as much as 30% of the 19 EJ that commercial buildings consume is considered excess. Much of the excess energy is due to the inability to manage building operations efficiently. Because almost 20% of the total primary energy consumption is associated with commercial buildings, significant energy reductions in this sector are needed to mitigate climate change. Therefore, many cities and states are mandating periodic “tune-ups” of these buildings to eliminate excess energy consumption. Although the benefits of tune-ups and retro-commissioning are clear, focusing these mandates to look for specific opportunities has been a challenge because of the lack of studies that document the prevalence of opportunities. Therefore, we analyzed building automation system data from 151 buildings across the United States to document common operational problems and opportunities to improve building operations. This analysis showed that opportunities to improve building operations exist in almost every building. These opportunities were not strongly correlated with building vintage or size, but were reflective of how the buildings are operated. The prevalence of the top 20 opportunities ranged between 74% and 23%, with 40% of these associated with air-handling units. The rest of the opportunities are associated with schedules, chilled and hot-water distribution, and zone controls. Of the 151 buildings, 69 of them implemented corrective actions of some or all opportunities that were identified. Implementation varied across the Re-tuning categories, with 60% for schedule opportunities, 50% for zone opportunities, over 40% for the air-handling unit and hot-water opportunities, and 35% of the chilled-water opportunities. There was wide variation in whole building energy savings, ranging from 0 to 50% and 0 to 18 $/m2 with median percent annual whole building savings of 12% and median normalized annual cost savings of $1.75/m2. In addition to documenting these key findings, the paper provides a list of opportunities that can be automatically and continuously identified and corrected and offers a list of those opportunities that should be the focus of the mandates.

Katipamula, Srinivas↗

Developing Flexible, Networked Lighting Control Systems That Reliably Save Energy in California Buildings

An important strategy to meet California's ambitious energy efficiency goals is to use innovative wireless communications, embedded sensors, data analytics and controls to significantly reduce lighting energy use in commercial buildings. This project developed a suite of networked lighting solutions to further this goal. The technologies include a platform for low-cost sensing, distributed intelligence and communications, the “PermaMote,” which is a self-powered sensor and controller for lighting applications. The project team also developed a task ambient daylighting system that integrates sensors with data-driven daylighting control using an open communication interface, called the “Readings-At-Desk” (RAD) system. To address the problem of building occupants being confused about how to operate traditional lighting control systems, the research team created content that could be the basis for a user interface standard for lighting controls. Finally, to address the difficulty of ensuring that advanced lighting control systems actually deliver their promised energy savings, the project team developed a new method for evaluating and specifying lighting systems’ performance. The research team validated these technologies in the laboratory, showing significant lighting energy savings, up to 73% for the PermaMote sensor system from occupancy control and daylight dimming features, compared to the same light source (LED replacement lamps) operated via simple on/off scheduling. The project team also developed a proposed standard lighting data model and user interface elements, which were contributed to the ANSI Lighting Systems Committee (C137) for standardization. Existing data models are incomplete and inconsistent, whereas the lighting-specific data model developed here is clear and comprehensive, to serve as a starting point for creating common, universally agreed upon semantic definitions of key lighting parameters, to promote interoperability. For the task on verifiable performance of lighting systems, the project team developed a more effective metric for capturing the actual energy impact of a lighting system over time — the energy usage intensity (kWh/ft2/year). Three commercial lighting systems were tested in FLEXLAB® using this new metric, and the tests show a wide range in the accuracy of the self-reported energy-use metric, from 0.5% to 28% error compared to direct measurement of lighting energy using dedicated submeters. Overall, the project team estimates that these advanced technologies can reduce California office lighting energy use by 20% (above and beyond normal advanced lighting controls mandated by Title 24), resulting in about 1,600 GWh/year in savings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Energy Savings Performance Contract Energy Sales Agreement Toolkit

FEMP developed the Energy Savings Performance Contracting Energy Sales Agreement (ESPC ESA) Toolkit to provide federal agency contracting officers and other acquisition team members with information that will facilitate the timely execution of ESPC ESA projects.

energy sales agreements↗

Energy Savings Performance Contract Energy Sales Agreements

An energy savings performance contract energy sales agreement (ESPC ESA) is a project structure, similar to a power purchase agreement, that uses the multiyear ESPC authority to implement renewable energy projects (referred to as ESA energy conservation measures [ECMs]) on federal buildings or land. The ESA ECM is initially privately owned for tax-incentive purposes, and the federal agency purchases the electricity it produces. An ESPC ESA is one of the most cost-effective methods for implementing on-site distributed energy projects at civilian federal agency sites.

energy savings performance contract↗