Energy Modeling
Sustainably Built offers energy modeling services to help clients make informed choices regarding energy efficiency measures. The model creates an estimate of savings for different measures, or packages of measures, allowing the client to rank different scenarios based on construction costs and lifetime estimated savings, and add that to other factors such as comfort and occupant health.
A detailed breakdown of the building shell components can aid the decision making process, identifying which materials and construction methods are the most cost-effective. By involving us in the project at the very beginning, we can help you make design decisions that will greatly affect energy efficiency while minimizing overall cost, maximising the value of the building.
In this example, you can see a graph of the heating loads of a house. This represents the total amount of heat lost through the shell of this house during winter. Every building design performs differently, but in this example we can see that our biggest heat loss comes from air infiltration (air leakage), and then from the above ground walls. So, first, we'd discuss construction systems and techniques that can reduce the overall air leakage in the house. Then we would consider a wall system that allows for more insulation, and so on. We do a similar analysis for cooling loss in the summer months.
View a sample report in pdf format.
Improvement Analysis
Not only can we determine how much the heat loss is reduced by various design changes and material upgrades, we can also estimate thel savings in utility bills. As we make changes to the design of the building, to the materials used in the building shell, and to the mechanical systems, we can consider an individualized cost/benefit ratio for each change. Some changes, such as moving windows to different orientations, can have zero difference in cost, but create dramatic savings in energy bills. Other changes will cost more than you will actually save in a thirty-year period, but the benefits of added comfort, safety, or durability could prove important enough to you to be worth the money.
In this example improvement analysis report, you can see the estimated money saved through a specific set of material upgrades. This report also compares the additional cost of the upgrades so you can see if your investment will pay off over time. Open the detailed report to see each line item. You can see the present value (PV), simple payback (SP), savings-to-investment ratio (SIR), and annual utility bill savings for each improvement. In this example, you'll see that a programable thermostat has the quickest return on investment, since the inital cost of the improvement is so low. Next in line are the installation of compact flourescent lighting and, again, reducing air leakage.
View the detailed improvement analysis report in pdf format.
We work with numerous energy modeling software platforms such as REM/Rate, EnergyPlus, eQUEST, PHPP (Passiv Haus Planning Package), Energy Gauge, RESFEN, RETSCREEN, and others. Each software platform has its strengths and weaknesses, and we utilize the most relevent programs for the job. You can watch a presentation about the differences between these programs here.
