Engineering Commons^™

Connected Water Heater Load Shifting And Energy Efficiency Evaluation For The Southeast: Winter Laboratory Assessment, Final Report, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

The University of Central Florida's FSEC Energy Research Center (FSEC) and Pacific Northwest National Laboratory (PNNL) are conducting laboratory electrical load shifting experiments using the CTA-2045-A standard to demonstrate the viability of grid-connected heat pump water heaters (HPWH), compared to electric resistance water heaters (ERWH), in providing load shifting in the Southeastern United States (U.S.). The investigation applied different CTA-2045 shed and critical peak (CP) control command designs under two different water draw profiles. The highly-controlled laboratory experiments were conducted on four HPWHs and one ERWH from December 2020 through February 2021.

The research aimed to evaluate the load shifting …

Targeting The Best Performing Home Efficiency Programs With Advanced Metering Evaluation Supplemented By Simulation, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The authors investigated the impacts of seven residential rebate energy efficiency programs offered by a municipal utility. The evaluation examined energy use pre and post retrofit using the Advanced Mete1ing Infrastructure (AMI) data, disaggregated by major end-use and weather-adjusted; and also by detailed simulations. Residences modeled were representative of typical participants for that measure based on factors such as year built, conditioned square feet and number of bedrooms.

Our analysis found the residential rebate programs to be of highly varied effectiveness, but important differences surfaced between the simulation and the AMI data evaluation. Not surprisingly, programs with larger samples tended …

Measured Performance Of A High-Efficiency Solar-Assisted Heat Pump Water Heater, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

This paper describes a novel solar photovoltaic-assisted heat pump water heater (PV-HPWH). The system uses two 310 Wp PV modules, micro-inverters and innovative controls to produce and store daily hot water. The system likely costs half that of solar thermal systems, with greater reliability, no freeze protection and potentially superior performance in cloudy locations. Moreover, no net metering is needed for the PV, which with two modules makes for a simple installation.The HPWH controls have been modified through experimentation such that higher tank temperatures are achieved during the day when solar availability is high while avoiding triggering the compressor during …

Improved Hot Water Code Calculation, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

The purpose of this report is to identify hot water waste sources, characterize the implications of climatic differences on hot water use and characterize the energy impacts of hot water recirculation systems and controls with respect to energy consumption in Florida homes, and recommend Florida-specific methods that can be employed in the Florida Energy Code for residential hot water use and energy consumption calculations.

Pv-Driven Heat Pump Water Heater Final Report, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

As part of the effort towards zero energy buildings and high efficiency water heating systems, the Florida Solar Energy Center (FSEC) working under contract with the National Renewable Energy laboratories (NREL) has successfully completed a demonstration of a photovoltaic heat pump water heater (PV-HPWH) concept. The system integrates two 310Wp solar photovoltaics (PV) modules and grid tied micro-inverters with a commercially available 50-gallon HPWH. The project showcases innovative strategies for distributed PV thermal systems that limit grid interaction and provide increased thermal energy storage. The system utilizes a custom appliance control module (ACM) interface to vary thermostat settings (115 °F …

Effect Of Ducted Hpwh On Space-Conditioning And Water Heating Energy Use -- Central Florida Lab Home, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWHs) on space-conditioning and water heating energy use in residential applications. Two identical HPWHs, each with a capacity of 60 gal, were tested side by side at the Flexible Residential Test Facility (FRTF) laboratories on the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The FRTF's residential buildings feature the same square footage (1,535 ft2 ), orientation, and envelope characteristics; currently, the only difference between them is the finished floor material. The east FRTF building is furnished with standard carpet flooring, whereas the …

Side-By-Side Testing Of Water Heating Systems: Results From The 2010-2011 Evaluation, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

REVISED MARCH 2013 The Building America (BAPIRC) team at FSEC has released a report containing results from a second testing rotation (Phase II) on seven hot water systems evaluated side-by side. Results show the seasonal performance variation and compares solar systems against electric resistance and the Heat Pump Water Heater (HPWH). Standard and tankless natural gas were also evaluated, where the latter demonstrated a 24% natural gas reduction. The lowest averaged electric power consumptions were demonstrated by the HPWH (2.75 kWh/day) and the PV-pumped solar water heater (3.03 kWh/day). Other testing performed on the HPWH under conditioned and restricted air …

Side-By-Side Testing Of Water Heating Systems Results From 2009-2010 Testing, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

The Hot Water System (HWS) Laboratory test facility at the Florida Solar Energy Center (FSEC) in Cocoa, FL was used for testing seven differing types of residential water heating systems. The HWS building provides unconditioned housing (similar to a garage in Florida) for one reference electric 50-gallon heater, three solar thermal electric assisted systems, one electric tankless system, one reference 40-gallon natural gas (NG) and tankless gas system. The performance of all seven systems has been compared in a side-by-side test configuration over a full year period. Simultaneous hot water draws take place for all hot water heating systems on …

How Energy Efficient Are Modern Dishwashers?, Florida Solar Energy Center, David Hoak

FSEC Energy Research Center®

We present measurements of three recent vintage dishwashers of very different efficiencies showing that while they are substantially more efficient than older dishwashers, those tested will still use electric resistance elements for supplemental heat, even when supplied by solar water heating systems producing very hot water. We did find the DOE test results provide a reasonable guide to comparative performance, but suggest improvements that will make them more representative. We also identify a variety of influences on efficiency and performance to reduce dishwasher energy use.

A Simplified Hot Water Distribution System Model, Florida Solar Energy Center, Lixing Gu

FSEC Energy Research Center®

Water heating in the U.S. has been identified as a major component of total energy consumption used in buildings, mostly coming from the residential sector at around 11%. A potential opportunity for energy savings in water heating systems is to improve the design of hot water distribution systems (HWDS). Due to the complex heat losses of HWDS, models are needed to optimize HWDS by reducing heat losses. There are three models currently used to simulate thermal performance of hot water distribution systems (HWDS): HWSim, ORNL-HWDS, and TRNSYS. The first two models are used to study hot water distribution systems only …

Solar Dhw Storage Tanks And Systems, Florida Solar Energy Center

FSEC Energy Research Center®

Water is by far the most common storage medium in solar domestic hot water systems. Rock storage is another method of sensible heat storage, but is not generally used in systems that are exclusively DHW. Storage of heat in solutions of phase-changing salts is extremely rare in DHVJ systems and therefore is not discussed.

Comparison Of Solar Hot Water Systems Simulated In Energygauge Usa And Trnsys 15, Florida Solar Energy Center, Michael Anello

FSEC Energy Research Center®

This document is meant to serve as a detailed summary of the comparison between the simulation methods of EnergyGauge USA and TRNSYS (version 15) relating to solar hot water systems. The initial motivation behind this comparison was to verify that the f-chart model created for EnergyGauge's solar hot water calculations was reporting the correct results. To this end, models of three systems were created in TRNSYS in order to serve as a baseline for the EnergyGauge results. The three systems modeled were: Liquid-active closed loop (LACL), Liquid-active open loop (LAOL), Integrated collector storage (ICS). This document will detail each of …

A Review Of Hot Water Draw Profiles Used In Performance Analysis Of Residential Domestic Hot Water Systems, Florida Solar Energy Center, Philip Fairey

FSEC Energy Research Center®

As a result of efforts on the part of various organizations to improve the specifications for performance-based analysis of energy use in residences, the literature on residential hot water use has been reviewed, specifically as it relates to typical hot water use draw profiles. A number of daily hot water use draw profiles have been identified and reviewed.

Fsec Approved Solar Energy Systems: Domestic Hot Water And Pool Heating, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

This listing contains Florida Energy Factors for solar domestic hot water systems that have been approved by the Florida Solar Energy Center (FSEC) for use in the State. These energy factors represent the dimensionless ratio of the hot water energy made available by each approved system divided by the electrical energy used by the system. The Florida Energy Factor (FEF) is used to determine hot water credit multipliers for residential solar water heating systems in the 1993 Florida Energy Efficiency Code for Building Construction. The FEF can also be used to compare the efficiency of solar water heating systems with …

Solar Thermal Billing Program In Florida, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

This paper presents the development, implementation, and results of Lakeland Electric's solar thermal billing program in Florida. The three-phase solar program was started in 1997 with funds from the Florida Energy Office (FEO) and the technical assistance of the Florida Solar Energy Center (FSEC). It was designed as a model to expand the concept of distributed energy generation, and to augment the use of solar domestic hot water (SDHW) systems. The solar thermal billing program relies on the proceeds generated from the sale of hot water energy. Twenty-nine SDHW systems, which are owned by Lakeland Electric (LE), gradually began operation …

Factors Influencing Water Heating Energy Use And Peak Demand In A Large Scale Residential Monitoring Study, Florida Solar Energy Center, Matthew Bouchelle

FSEC Energy Research Center®

A load research project by the Florida Power Corporation (FPC) is monitoring 204 residences in Central Florida, collecting detailed end-use load data. The monitoring is being performed to better estimate the impact of FPC's load control program, as well as obtain improved appliance energy consumption indexes and load profiles. A portion of the monitoring measures water heater energy use and demand in each home on a 15-minute basis. The paper summarizes the various impacts identified on water heating energy use and demand.

Measured Energy Savings From Retrofits Installed In Low-Income Housing In A Hot And Humid Climate, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) is metering energy use in a Habitat for Humanity housing development. The objective is to understand the way in which energy is used in low income housing and how it can be effectively reduced.

The ten homes come from a conventional housing project built by in 1993 Habitat for Humanity in Homestead, Florida. The instrumentation was installed in the homes in July of 1994 with over three years of 15-minute data collected on all sites. Data were obtained on seven electrical end-uses (air conditioning, heating, hot water, dryer, range, refrigerator, washer/freezer) as well as …

Solar Hot Water Energy And Cost Savings For Typical Florida Residential Installations, Florida Solar Energy Center, David Block

FSEC Energy Research Center®

The following table presents energy and cost savings for four typical Florida solar water heating systems. Exact savings by a consumer may vary as much as plus or minus 25 from these numbers for numerous reasons. These include hot water usage, storage tank type, thermostat settings, solar system size, collector placement and local weather conditions. Computer simulations were used to generate the energy data.

Solar Heating Of Swimming Pools: A Question & Answer Primer, Florida Solar Energy Center, Charles Cromer

FSEC Energy Research Center®

Solar pool heating is one of the most economically attractive solar technologies in Florida today. If you are interested in heating your pool, or can no longer afford heating it with fossil fuel alone, consider installing a solar pool heater.

The following information helps answer the most frequently asked questions concerning solar pool heating in Florida. Keep in mind that much of this information is "rule of thumb"; your individual situation, if analyzed in detail, may differ somewhat from the general application. A more detailed analysis of pool systems is provided by the publications listed in the bibliography.

Rebuilding For Efficiency: Improving The Energy Use Of Reconstructed Residences In South Florida, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

On August 24th, 1992, Hurricane Andrew devastated a large part of South Dade County in Florida. With over 35,000 homes to be rebuilt, there is interest in seeing if these reconstructed residences can be made more energy-efficient.

This report provides a comprehensive assessment of potential energy efficiency improvements for both new and existing homes in South Florida. Over forty energy-efficiency measures were considered in the analysis. Many homes in the effected zone experienced damage to their windows, roofs and the surrounding landscape. As a result, the analysis closely examined options associated with these design aspects. All major end-uses of electricity …

Simplified Sizing Procedure For Solar Domestic Hot Water Systems, Florida Solar Energy Center, Public Information Office

FSEC Energy Research Center®

This procedure was developed to size residential solar water heating systems in Florida.

Electrical Use, Efficiency, And Peak Demand Of Electric Resistance, Heat Pump, Desuperheater, And Solar Hot Water Systems, Florida Solar Energy Center, Timothy Merrigan

FSEC Energy Research Center®

Eighty single family residences in Florida were monitored for two years in order to collect data on water heating electrical energy consumption, efficiency, and time-of-day demand. The homes were divided into equally sized samples of four different water heating systems: conventional electric resistance, heat pump, desuperheater and solar hot water systems. Electrical consumption for electric resistance water heaters averaged 8.3 kWh per day in Florida with an average water heating system efficiency of 82%. Desuperheaters used an annual average of 7.4 kWh per day at an annual system efficiency of 110% and heat pump water heaters used 6.1 kWh per …

Solar Water Heater Troubleshooting Checklist, Florida Solar Energy Center

FSEC Energy Research Center®

Lists the Symptom, Component, Possible Cause, and Remedy/Check of possible solar hot water heater problems.