Detailed energy model of the National Institute of Standards and Technology Net-Zero Energy Residential Test Facility: Development, modification, and validation

Abstract

The NIST Net-Zero Energy Residential Test Facility (NZERTF) is a highly instrumented, highly configurable, single-family, net-zero energy house occupied by a virtual family of four. A detailed transient model of the NZERTF and the accompanying mechanical equipment was created using information available before construction; the model incorporated building geometric details and construction material properties, as well as manufacturers’ specifications for HVAC, water heating, solar PV and other equipment. This model represents the typical design paradigm, where actual building performance and detailed equipment operation are not known. This original model underpredicted the measured annual energy consumption by 13.8 %. The measured data were used to understand and correct the sources of error at the component level; modifications to the HVAC system, interior thermal capacitance, and domestic hot water system improved the energy consumption prediction to within 1.6 % of measured data. The differences between the original and modified models are useful for understanding the sources, magnitudes, and possible corrections to errors in energy models for high-efficiency residences. The modified model will be used in future studies of alternative energy system configurations and control strategies, contributing to cost-effective and optimum design of net-zero energy houses in America.

An assessment of efficient water heating options for an all-electric single family residence in a mixed-humid climate

“…An overview of the model will be presented here; see Balke et al [26,27] for a more complete description.…”

“…The delivered energy was predicted to within 3%. Balke et al [27] note the challenges faced in matching experimental data on account of the uncertainty in the control scheme of the resistance element in the HPWH. The tuned models of the SWH and the HPWH were then used as part of this study of alternative configurations.…”

Assessing the performance of residential energy management control algorithms:

“…Residential EMCA5 was designed to replicate the heat pump controller used in the Net-Zero Energy Residential Test Facility (NZERTF) and the simulation results were validated with experimentally measured performance [28]. In the heating season, residential EMCA5 uses the heating lower bound temperatures, as given in Table 6, to manage the operation of the heat pump.…”

Assessing the performance of residential energy management control algorithms: multi-criteria decision making using the analytical hierarchy process

“…Residential EMCA5 was designed, as a best effort, to replicate the operation of the heat pump differential controllers used a TRNSYS model of the Net-Zero Energy Residential Test Facility (NZERTF) [28]. In the heating season, residential EMCA5 uses the heating lower bound temperatures, as given in Table 6, to manage the operation of the heat pump.…”

“…The residential EMCAs were linked to a TRNSYS simulation model [28] of the NZERTF at NIST in Gaithersburg, Maryland [29]. Measured data from the NZERTF were used to validate the model.…”