Report Number




EnergyGauge; Energy Efficiency; Buildings


You need special tools to design high-performance homes - residences where energy efficiency creates greater comfort, health, and energy savings. Making decisions about energy efficiency requires the accurate calculation of energy use and demand, and the comprehensive evaluation of proposed improvements.

A new software tool helps meet these requirements. EnergyGauge USA, an hourly simulation tool for the design and analysis of high-performance homes, performs detailed hourly simulation analysis for energy use, ratings and code calculations. Version 2.0 adds many features to the first-generation product, including thermal mass, photovoltaic (PV) system simulation, solar water heating, and detailed hourly outputs.

The software, designed by the Florida Solar Energy Center (FSEC), provides a user-friendly front end to simulate a residential building. It uses the DOE-2 engine with new functions, including a detailed attic model, thermal distribution systems, and HVAC performance modeling (see Parker et. al, 1999). The software has three entry modes: International Energy Conservation Code (IECC), rating, and detailed. Under detailed entry mode, all inputs are available to the user for altering. Code and rating entry modes do not allow certain variables to be altered due to the governing rules. For a typical building, Version 2 computes an annual energy analysis in less than five seconds on a 2.4 Ghz machine.

Calculations include annual energy use, IECC calculation, energy ratings, system-sizing based on ACCA Manual J seventh edition, and economic analysis of improvements. The program has passed the HERS BestTest (Fairey et. al), a verification procedure developed by the National Renewable Energy Laboratory (NREL) to determine the accuracy and effectiveness of the energy load prediction capability of software tools used for home energy ratings. EnergyGauge USA has also been verified against measured data (see Figure 1 and Fuehrlein, et. al.).

Date Published



Reference Publication: Vieira, Robin, "Sunup to Sundown," Software/Web column for HomeEnergy, Berkeley, CA, January/February 2003, pp 10,11. Figures and references expanded.

Local Subjects

Buildings - Energy Efficiency; Buildings - EnergyGauge


FSEC Energy Research Center® Collection



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