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In recent years, residential lighting has represented a significant share of ratepayer-funded energy-efficiency electricity savings. Utilities have achieved the majority of these savings by promoting the purchase and installation of compact fluorescent lamps (CFLs), both standard 'twister' bulbs and specialty CFLs such as reflectors, A-Lamps, globes, and dimmable lights.
Given new regulations, increased complexity in the market, and the general shift from CFLs to LEDs, this evaluation protocol was updated in 2017 to shift the focus of the protocols toward LEDs and away from CFLs and to resolve evaluation uncertainties affecting residential lighting incentive programs.
Efficient lighting for the residential sector in South Africa stemmed out of an electricity supply crisis. The Compact Fluorescent Lamps (CFL) rollout programme was carried out in the absence of a supporting policy. The implementation resulted in both desirable and undesirable outcomes. Of even greater concern is that a section of the market may be regressing to inefficient lighting. An analysis of lighting technologies available in the market shows that a shift to more energy efficient lighting technologies, such as light-emitting diodes (LED), will result in significant energy savings.
Solid-state lighting (SSL) technologies have penetrated the general illumination market in recent years, largely replacing conventional technologies such as incandescent and fluorescent lighting. Most of the initial excitement about light-emitting diode (LED) sources for SSL devices focused on their energy savings potential resulting from vast improvements in source efficiency and luminous efficacy compared with conventional illumination products. More recently, the focus has shifted toward other aspects of lighting application efficiency, namely intensity effectiveness and spectral efficiency, because of the ease of controlling both the light intensity of LEDs with drive voltage and the color properties of the LED-based illuminators. To capitalize on the energy savings of increased intensity effectiveness and spectral efficiency, a lighting control system (LCS) is often used. While the current penetration of LCSs is relatively modest, it is anticipated that lighting controls (i.e., connected lighting, controls and LED and conventional lighting) could have an installed penetration as higher as 46% by the year 2035, saving an additional 1.3 quads of energy. Despite the large energy savings that can be gained from using LCSs, standard test methods for evaluating sensors employed in LCSs and reliability data of the LCSs and their components are generally lacking. The National Electrical Manufacturers Association (NEMA) developed the only standard, NEMA WD 7-2011 (R2016), to test occupancy and motion sensor performance (herein referred to as “the NEMA protocol”). In a previous U.S. Department of Energy (DOE) effort, some concerns of the NEMA protocol were identified (e.g., strict height and weight limits on test subjects, large amounts of manual effort, sometimes inconsistent repeatability). During the current work, a consistent detection length test (DLT) and a Robotic Sensor Evaluation System (RoboSES) were developed to alleviate some of these concerns. RoboSES acts as a human surrogate by using thermal pads on a mannequin and a remote-controlled mobile base to test a sensor’s field of view (FOV). This report builds on the earlier DOE efforts to understand sensor technologies used in LCSs for general illumination. Specifically, this report describes the optimization of RoboSES, characterizes and establishes test methods to assess the reliability of multiple passive infrared (PIR) sensors, and reports the findings of robustness and reliability testing on two commercial PIR sensors intended for residential applications. The information presented in this report is gained from up to 4,000 hours (hrs) of accelerated stress tests (ASTs).
This is the complete set of Uniform Methods Project protocols for determining energy efficiency savings for specific measures, all within one report. The report includes the following chapters: Chapter 1: Introduction. Chapter 2: Commercial and Industrial Lighting Evaluation Protocol. Chapter 3: Commercial and Industrial Lighting Controls Evaluation Protocol. Chapter 4: Small Commercial and Residential Unitary and Split System HVAC Cooling Equipment-Efficiency Upgrade Evaluation Protocol. Chapter 5: Residential Furnaces and Boilers Evaluation Protocol. Chapter 6: Residential Lighting Evaluation Protocol. Chapter 7: Refrigerator Recycling Evaluation Protocol. Chapter 8: Whole-Building Retrofit with Consumption Data Analysis Evaluation Protocol. Chapter 9: Metering Cross-Cutting Protocol. Chapter 10: Peak Demand and Time-Differentiated Energy Savings Cross-Cutting Protocol. Chapter 11: Sample Design Cross-Cutting Protocol. Chapter 12: Survey Design and Implementation for Estimating Gross Savings Cross-Cutting Protocol. Chapter 13: Assessing Persistence and Other Evaluation Issues Cross-Cutting Protocol. Chapter 14: Chiller Evaluation Protocol. Chapter 15: Commercial New Construction Evaluation Protocol. Chapter 16: Retrocommissioning Evaluation Protocol. Chapter 17: Residential Behavior Evaluation Protocol. Chapter 18: Variable Frequency Drive Evaluation Protocol. Chapter 19: HVAC Controls (DDC/EMS/BAS) Evaluation Protocol. Chapter 20: Data. Center IT Efficiency Measures Evaluation Protocol. Chapter 21: Estimating Net Savings - Common Practices. Chapter 22: Compressed Air Evaluation Protocol. Chapter 23: Combined Heat and Power Evaluation Protocol. Chapter 24: Strategic Energy Management (SEM) Evaluation Protocol
This paper examines the waste burden associated with an evolving waste stream: residential lighting. To understand the impact of lighting we used life cycle assessment analysis of LED products. We developed several personas representing different pats of the product adoption curve to quantify the volume and change rate of lighting products. The personas have also been used to estimate the waste impact for larger populations. The results indicate that the waste burden of high performance lighting still requires recycling programs and policies to prevent significant levels of waste to landfills. The results also confirm that attention must be paid to how to reduce the waste burden of LED lighting products through improved design.
Adaptive lighting is an approach to lighting application in which the lighting levels are controlled based on the needs of the users of the lighted environment. Such systems are enabled by the instant-on and dimming capabilities of solid-state lighting and have been shown to have the potential to reduce energy consumption by over 50%, both through the use of maintained lighting levels without over-lighting and dimming. This investigation considered the impact of adaptive lighting within Cambridge NA. The impact of adaptive lighting on crashes and crime was considered using both the timing of the installation of the LED system in a before-and-after comparison, as well as a comparison to a neighboring non-dimming city. Industry practitioners and the public were also surveyed. As a follow-on to the first analysis, a human factors experiment was performed to investigate if the lighting levels could be further refined to improve energy performance. Overall, the energy savings from the dimming system range from 55% initially to 36% at the end of the life of the luminaire system
We present the results of a 2019 online survey of 1,800 adults in the United States who recently purchased a light bulb to understand how consumers make decisions about purchasing light bulbs and how light bulbs are used in the residential sector. From our survey, we found that purchases of LED bulbs made up the largest percentage of sales by lighting technology and respondents generally had positive impressions of LEDs. We estimated the average daily hours of use for bulbs being purchased depending on bulb shape. We also provide an estimate for the lumen distribution of purchased light bulbs and the distribution of installation locations by bulb shape. We found that incandescent bulb purchasers were primarily replacing a failed incandescent bulb and these purchasers were less likely to have favorable impressions of LEDs. However, we found that the majority of participants replacing an incandescent bulb purchased either a CFL or LED. Using an adaptive conjoint analysis technique, we found that the five most important factors to consumers when choosing a light bulb are purchase price, bulb lifetime, energy cost savings relative to an incandescent bulb, light appearance, and energy savings relative to an incandescent bulb. The results of this study provide an in-depth look at the lighting market in 2019 and may provide a basis for developing models of the residential lighting market.
U.S. buildings account for approximately 40% of total U.S. energy consumption and 75% of electricity use, emphasizing the need for efficient, resilient, and secure energy solutions. Micro-combined heat and power (micro-CHP) systems provide an effective approach by simultaneously generating electricity and recovering waste heat for thermal use. However, current commercial micro-CHPs face challenges in achieving higher efficiency, lower emissions, and reduced cost. To address these limitations, a novel micro-CHP prototype powered by a unique opposed-piston four-stroke (OP4S) engine was developed. The OP4S features a simplified, low-cost design with reduced heat losses and dual-piston operation that enables higher thermal efficiency. Experimental results demonstrated up to 35.2% AC electrical efficiency under lean combustion, surpassing the best-performing ICE-based micro-CHPs reported publicly. In addition, the micro-CHP enables a total CHP efficiency exceeding 93%. The prototype operates reliably for over 600 hours, providing flexible and efficient thermal and electrical outputs. This novel OP4S-based micro-CHP offers a resilient, low-cost, and energy-efficient solution suitable for residential, light commercial, and remote community applications across diverse climate zones.
In November 1990, an inspection visit was made to the residential lighting photovoltaic systems that had been installed approximately one year before in the rural communities of the Municipality of Pinotepa de Don Luis, in the State of Oaxaca. The main purpose of the visit was to evaluate the physical and operational status of these systems. The systems typically consist of a photovoltaic module with a capacity of 30 or 35 Watts, an automotive type battery, an indicator of the status of charge of the battery, 3 fluorescent lamps and the corresponding installation, including cables, connection or outlet box and switches. It can be seen that the systems are in good physical condition and do not show any signs of intentionally caused damage. However, the incidence of failures is higher than what had been expected; therefore the operational status of these systems is considered to be below a level that could be accepted, with a tendency to getting worse. The main problem that has been detected is the lack of automatic charge controllers. This problem has caused other important failures. Serious deficiencies were appreciated in the installations, which show evidence of the poor workmanship of the installers. The lack of system standardization is evident, both regarding the components and the installation. As a consequence, there are technical factors which indicate that the installed systems will keep deteriorating at a rate faster than normal, and will stop operating in a short time unless urgent preventive and corrective measures are taken. The attitude of the users with respect to the systems is generally positive. However, there are elements that make the correct operation and maintenance of these systems a very difficult task. The users did not receive any training regarding the best way to operate and take care of their systems, nor any other information in relation to their technical limitations.
A micro–combined heat and power (mCHP) prototype powered by innovative opposed piston engine technology was developed to simultaneously provide electricity and heat to residential or light commercial buildings. The mCHP prototype targeted at residential applications includes an opposed-piston four-stroke (OP4S) engine, generator, rectifier, inverter, battery energy storage system, 52 gal water tank, and application accessories for hot water supply and space heating. The OP4S engine can use renewable or regular natural gas, as well as hydrogen, to generate mechanical power and waste heat in form of hot coolant and exhaust gas simultaneously. The waste heat is recovered and stored in the water tank and can be used as a regular hot water supply and/or for space heating application. The tests show that the mCHP prototype enabled power outputs in the range of 3.2 –7.4 kW with up to 26.4% of AC electricity efficiency and up to 93.1% of the overall mCHP efficiency under stoichiometric combustion modes λ=~1.0. The mCHP was also run under lean combustion mode conditions at λ=~1.3. The lean mode operation enables more than 30% improvement in electrical energy efficiency. The maximum AC efficiency of the lean combustion mode attained was 35.2%, with the engine efficiency is approaching 40%. The exceptional electrical efficiency breaks the typical upper boundary of 30% for ICE-based mCHP. The engine exhaust temperatures in the lean modes are substantially less than in the stoichiometric modes. Moreover, the lean cases achieve high overall mCHP efficiencies: the overall mCHP efficiencies are all greater than 93%. Considering the mCHP prototype can achieve low-cost, flexible matching of thermal and electrical loads through reducing the complexity of distribution and installation, and high efficiency the novel technology will promote mCHP acceptance in the US residential and light commercial markets.
This report summarizes the Large Scale (LS) simulation platform created for the Eaton NODES project. The simulation environment consists of both wholesale market simulator and distribution simulator and includes the CAISO wholesale market model and a PG&E footprint of 25-75 feeders to validate the scalability under a scenario of 33% RPS in California with additional 17% of DERS coming from distribution and customers. The simulator can generate hourly unit commitment, 5-minute economic dispatch, and 4-second AGC regulation signals. The simulator is also capable of simulating greater than 10k individual controllable devices. Simulated DERs include water heaters, EVs, residential and light commercial HVAC/buildings, and residential-level battery storage. Feeder-level voltage regulators and capacitor banks are also simulated for feeder-level real and reactive power management and Vol/Var control.
The past decade has witnessed the rapid adoption of electric vehicles (EVs). The momentum is expected to continue with strong support from the government and industry. Rapid EV adoption brings significant charging demand to the power grid, causing additional stress and non-negligible risks to the already-aging power grid. To help power grid operators understand the impacts of EV home charging on the grid and identify risk factors, this study presents a data-driven residential charging demand analysis for light-duty vehicles. This study considers two real-world grid service regions in Colorado and merges multiple data sources and state-of-the-art tools that characterize EV adoption projections, vehicle travel patterns, seasonal variations, residential charging accessibility, ambient temperature impact, EV charging behaviors, grid utility customers, vehicle registration, and household-level EV charging demand distribution. We characterize potential residential charging demand in 2030 for two regions within the state of Colorado: Boulder and Aurora. We project that EVs will be 26% of the light-duty vehicle population in Boulder and 16% in Aurora. Charging demand is characterized for ten power grid feeders (five for each study region). Across the ten feeders, peak total EV charging powers during wintertime range from less than 1 MW to more than 4 MW.
The past decade has witnessed a remarkable surge in adoption of electric vehicles (EVs). The momentum is expected to continue with strong support from governments and industry. Rapid EV adoption will add significant electricity demand, making it critical to plan for and manage EV charging to avoid causing additional stress and non-negligible risks to the already-aging power grid. To help power grid operators understand the impacts of residential EV charging and identify risk factors, this study presents a data-driven charging demand analysis for light-duty vehicles. This study considers two real-world grid service regions in Colorado and merges multiple data sources and state-of-the-art tools that characterize EV adoption projections, vehicle travel patterns, seasonal variations, residential charging accessibility, ambient temperature impact, EV charging behaviors, grid utility customers, vehicle registration, and household-level EV charging demand distribution. We characterize potential residential charging demand in 2030 for two regions within the state of Colorado: Boulder and Aurora regions. We project that EVs will be 26% of the light-duty vehicle population in Boulder and 16% in Aurora areas. Charging demand is characterized for ten power grid feeders (five for each study region). Across the ten feeders, peak total EV charging powers during wintertime range from less than 1 MW to more than 4 MW.
The program administrator and total cost of saved energy allow comparison of the cost of efficiency across utilities, states, and program types, and can identify potential performance improvements. Comparing program administrator cost with the total cost of saved energy can indicate the degree to which programs leverage investment by participants. Based on reported total costs and savings information for U.S. utility efficiency programs from 2009 to 2013, here we estimate the savings-weighted average total cost of saved electricity across 20 states at 0.046 per kilowatt-hour (kW h), comparing favorably with energy supply costs and retail rates. Programs targeted on the residential market averaged 0.030 per kW h compared to 0.053 per kW h for non-residential programs. Lighting programs, with an average total cost of 0.018 per kW h, drove lower savings costs in the residential market. We provide estimates for the most common program types and find that program administrators and participants on average are splitting the costs of efficiency in half. More consistent, standardized and complete reporting on efficiency programs is needed. Differing definitions and quantification of costs, savings and savings lifetimes pose challenges for comparing program results. Reducing these uncertainties could increase confidence in efficiency as a resource among planners and policymakers.
The Annual Fuel Utilization Efficiency (AFUE) analysis of residential and light commercial furnaces follows ANSI/ASHRAE Standard 103-2017 (i.e., Method of Testing for Annual Fuel Utilization Efficiency of Residential Central Furnaces and Boilers) . The analysis is a complex, comprehensive method based on furnace configuration and specific components equipped, requiring detailed furnace testing and measurement data. For this reason, an AFUE Analysis Tool using Microsoft Excel enabled with Visual Basic for Applications (VBA) was developed with a user-friendly interface and comprehensive coverage. The tool consists of three worksheets: unit and configuration selection, geometry and measurement data input, and AFUE plus key results. This tool can be used to estimate the AFUE of both condensing and noncondensing furnaces with single-stage, two-stage, and step-modulating functions. The tool was validated with experimental data from Oak Ridge National Laboratory’s natural gas furnace projects that are commercially available. The results indicate the tool is reasonably accurate in the evaluation of a new R&D modified furnace unit.
Through the Communities LEAP (Local Energy Action Program) Pilot, the National Renewable Energy Laboratory (NREL) engaged the Highland Park Stakeholder Coalition to scope four technical assistance work areas to address their energy needs and goals. This slide deck addresses the highlighted tasks under work area "A" related to the city's streetlights. Due to economic collapse, the City of Highland Park negotiated repossession of it's neighborhood streetlights to help pay its debt to its power provider, DTE. Without street lighting on residential streets, public safety was at risk. Local community-based-organization, Soulardarity, began installing off-grid solar street lights to improve visibility for vehicles and pedestrians in Highland Parks neighborhoods. Residents and leaders of the community who served on the Communities LEAP Coalition requested NREL review a financial model Soulardarity proposed to operate a city-wide solar streetlighting program on the City's behalf. The coalition also requested NREL identify examples of similar implemented city-wide solar street lighting programs.
The Woods is a 30-home, high- performance, energy efficient sustainable community built by Habitat for Humanity (HFH). With Support from Tacoma Public Utilities, Washington State University (part of the Building America Partnership for Improved Residential Construction) is researching the energy performance of these homes and the ductless heat pumps (DHP) they employ. This project provides Building America with an opportunity to: field test HVAC equipment, ventilation system air flows, building envelope tightness, lighting, appliance, and other input data that are required for preliminary Building Energy Optimization (BEopt™) modeling and ENERGY STAR® field verification; analyze cost data from HFH and other sources related to building-efficiency measures that focus on the DHP/hybrid heating system and heat recovery ventilation system; evaluate the thermal performance and cost benefit of DHP/hybrid heating systems in these homes from the perspective of homeowners; compare the space heating energy consumption of a DHP/electric resistance (ER) hybrid heating system to that of a traditional zonal ER heating system; conduct weekly "flip-flop tests" to compare space heating, temperature, and relative humidity in ER zonal heating mode to DHP/ER mode.