Using energy modeling, you can figure out which energy-saving improvements are the most cost-effective options. The use of energy modeling software during the design process aids builders in determining the most cost-effective ways to develop a zero-energy home. A ground source heat pump vs. an air source heat pump comparison should be made, as should the impact of R-30 wall insulation vs. R-60 wall insulation on the energy impact of alternative design choices.
Preliminary designs containing measurements, elevations, a basic floor plan, and windows and doors allow for quick energy modeling. As a consequence of the modeling, the designs can be fine-tuned to ensure that the project meets its zero-energy target at the lowest possible cost. Plans and construction documentation must incorporate decisions made during energy modeling. The payback period for energy modeling costs is surprisingly short, at only a few months.
Energy-saving upgrades that save more energy for the same dollar per kilowatt-hour than the cost of installing PV are considered cost-effective and should be included in the design. After rebates and tax incentives, the additional expenditures for building a zero-energy home can be as low as 5 percent of the sales price if energy modeling is used to help ensure the cost efficiency of energy saving measures.
When comparing the relative energy savings of various improvements, it’s critical to account for the associated costs. Upgrading an energy-saving feature beyond a certain degree may no longer be cost-effective because further upgrades will yield diminishing returns. Similar to this, upgrading one component will have an impact on the impact of upgrading others. Using energy modeling, we can figure out when efficiency returns become unprofitable and which energy-saving initiatives result in the greatest savings.
It’s difficult to determine the actual net cost of various energy-saving solutions because they change over time and depend on the market for residential development. Energy modeling, on the other hand, provides useful information about the relative costs and benefits of various energy-saving measures.
The following links provide information about some of the different energy modeling software that is available:
Energy Gauge, Florida Solar Energy Center
Energy 10, Sustainable Buildings Industry Council (SBIC)
REM Design It is not the most precise or comprehensive energy modeling application, but it is simple to use and delivers some of the most useful energy modeling comparisons rapidly and readily available today Certified home energy raters utilize REM/Rate, a program that is essentially equivalent to REM.
EnergyPlus Published by the U.S. Department of Energy, this is a highly sophisticated modeling engine.
BeOpt, National Renewable Energy Laboratory. BeOpt is unusual in that it lets users compare a large number of options side by side. The program provides a cost-effective package for designing a zero-energy home based on the price of each option. EnergyPlus now has a user-friendly graphical interface. Learn more about BeOpt from the Green Building Advisor.
HEED shows how much energy and money and carbon you can save by making various design or remodeling changes to a home with this free new easy-to-use program. You can draw in the floor plan of a house, then click and drag windows to their correct location.
Passive House Planning (Design) Package, (PHPP), Passive House Institute. PHPP may well be the ultimate in energy modeling, however it requires very detailed information and can be time-consuming and expensive. To use this program effectively, you must attend Passive House Consultant training.
Building Energy Software Tools Directory, U.S. Department of Energy. This is a comprehensive and alphabetical directory of energy modeling programs, gathered by the U.S. Department of Energy.
Carbon Foot Print and Life Cycle Assessment Software
Reaching net zero energy for building operation is only the first step.. End-of-life structures must be carbon neutral in terms of both materials and construction techniques, as well as operational energy use. Building designers and architects can use Life Cycle Assessment (LCA) software to determine the carbon footprint of their designs and make changes to them if necessary to reduce that footprint. In order to execute standards-based life cycle assessments, carbon footprinting, and work pricing, designers input building data from X-cel, Revit, and BIM applications using LCA software is One Click LCA. More later on Carbon Neutral construction.