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 …

Maximizing The Effectiveness Of Ductless Heat Pumps In Existing Homes By Demonstrating Integrated Controls: Measurement And Verification Plan, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

There is a trend for homeowners to install efficient ductless air-source heat pumps (ASHP) as a supplement to less efficient existing space conditioning systems, with most homeowners adding one unit in a central living area. Because of the potential for ASHPs to save energy by providing a large portion of the space conditioning, utilities have incentivized this strategy. However, post installation evaluations suggest ASHPs are not reaching their full potential because the existing heating system continues to operate more than necessary. This report describes a measurement and verifications strategy for a research project that aims to maximize savings from supplemental …

Evaluating Moisture Control Of Variable-Capacity Heat Pumps In Mechanically Ventilated, Low-Load Homes In Climate Zone 2a, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

The well-sealed, highly insulated building enclosures constructed by today's home building industry coupled with efficient lighting and appliances are achieving significantly reduced heating and cooling loads. These low-load homes can present a challenge when selecting appropriate space-conditioning equipment. Conventional, fixed-capacity heating and cooling equipment is often oversized for small homes, causing increased first costs and operating costs. Even if fixed-capacity equipment can be properly specified for peak loads, it remains oversized for use during much of the year. During these part-load cooling hours, oversized equipment meets the target dry-bulb temperatures very quickly, often without sufficient opportunity for moisture control. The …

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 …

Final Report: Cooling Seasonal Energy And Peak Demand Impacts Of Improved Duct Insulation On Fixed-Capacity (Seer 13) And Variable-Capacity (Seer 22) Heat Pumps, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Previous phase 1, 2, and 3 research identified that duct conductive losses to an attic environment imposed greater relative energy losses for the variable-capacity systems compared to the fixed-capacity systems (Cummings and Withers 2011) because of the longer dwell time of conditioned air in the ducts. The purpose of the Phase 4 experiments reported here was to see if duct R-value enhancement would benefit the overall operating efficiency of the variable-capacity system relatively more than the fixed-capacity system. The current Phase 4 experiments (the primary focus of this report) found that this was a secondary effect.

Cooling And Heating Season Impacts Of Right-Sizing Of Fixed- And Variable-Capacity Heat Pumps With Attic And Indoor Ductwork, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The U.S. Department of Energy's research team Building America Partnership for Advanced Residential Construction implemented two phases of experiments to examine the cooling and heating seasonal and peak demand performance of a variable-capacity 2-ton SEER 22 heat pump versus a 3-ton variable-capacity SEER 21 heat pump with attic ducts and indoor ducts. The experiments also compared the cooling and heating seasonal and peak demand performance of 2-ton versus 3-ton fixed-capacity SEER 13 heat pumps with attic ducts and indoor ducts.

Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump And Heat Recovery Equipment In Energyplus, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow air conditioning (VRF AC) manufacturers, provided a detailed computer model for a VRF AC system in the United States Department of Energy's (U.S. DOE) EnergyPlus' building energy simulation tool. No other simulation tool currently has the capability to accurately model this state-of-the-art VRF heating, ventilating, and air conditioning (HVAC) equipment. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance with that predicted by the use of this new model through computer simulation.

This project …

Creating Performance Curves For Variable Refrigerant Flow Heat Pumps In Energyplus, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

This document describes methods to generate performance curve coefficients for variable refrigerant flow heat pumps in DOE's EnergyPlus building energy simulation program. Manufactures performance data for capacity and power are used to create full-load and part-load performance curves for cooling and heating operating modes. When performance variations for full-load capacity or power cannot be modeled using a single performance curve, the data set is divided into lower and upper temperature regions and dual performance curves are used. Table objects may also be created to substitute when performance curves do not provide the required accuracy. These performance curves or tables are …

Comparison Of The Energygauge Usa And Beopt Building Energy Simulation Programs, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Two hourly energy simulation software, BEopt and Energy Gauge USA, were compared to ensure accuracy and evaluate agreement on the impact of various energy efficiency improvements. Within the Building America program, these software aid design teams working toward the U.S. Department of Energy's goal to make Zero Energy Homes economically viable by 2025. Builders use the software to achieve the extensive energy savings (70%-80%) from various measures before adding solar electric power generation. The study found that in general, BEopt and EnergyGauge USA agree fairly well on the impact of energy efficiency improvements, while identifying several discrepancies that need further …

Factors Influencing Space Heat And Heat Pump Efficiency From A Large-Scale Residential Monitoring Study, Florida Solar Energy Center, Matthew Bouchelle

FSEC Energy Research Center®

Since Florida utilities often experience their system peak during the state's few cold mornings, understanding influences on space heat performance is important to controlling demand. Analysis of heat pump impacts on system load in a large scale monitoring study have shown large levels of strip heat being used during the winter morning peak. The implied coefficient of performance of heat pumps during the system peak hour was only 1.30. Also, analysis of the total seasonal space heat has shown that the implied Heating Season Performance Factor (HSPF) of heat pump homes is only 4.4 Btu/W rather than the 6-8 Btu/W …