Author’s Corner
In this white paper, Richard Black, Director Engineering Operations, examines energy modeling’s rapid growth in the battle against climate change. Richard also discusses examples of savings that can be made with energy modeling.
Please click on the video to the right to learn more about the author, his paper’s main arguments, and building energy modeling,
To talk about this white paper in more detail, please contact the author using the information provided at the end of the article.
Energy modeling or energy system modeling is the process of building computer models of energy systems to analyze them. Such models often employ scenario analysis to investigate different assumptions about the technical and economic conditions at play.
Energy modeling has increased in importance as the need for climate change mitigation has grown in importance. The use and application of energy modeling (especially BEM) gives significant results and savings right from the start.
Building Energy Modeling (BEM)
Building Energy Modeling (BEM) is the practice of using computer-based simulation software to perform a detailed analysis of a building’s energy use and energy-using systems. An energy modeler will input data to create the building model, including weather, building orientation, geometry, constructions, occupant schedules, and energy-using equipment.
Results are typically reported for annual performance and include the space cooling and heating loads, daylighting impacts, equipment energy use, resource consumption, energy costs, and other performance-related parameters. BEM provides a number of benefits to both new construction and retrofit projects. The expense of modeling services usually represents a marginal incremental cost to the project, yet can influence significant reductions in annual energy costs.
In general, there are three ways that BEM can provide value to a project and benefit the owner:
- Reduced first costs
- Reduced operating costs
- Improved occupant satisfaction
Figure 1
Incorporating BEM within building efficiency projects has become increasingly common as owners recognize its value for improving existing building performance or supporting the design of high-performance buildings. Applications are categorized by their general modeling purpose; modeling to compare, modeling to comply or modeling to predict.
Examples of savings to be made by Energy Modeling
Theoretical savings can be extremely high as the BEM is applied to both new and existing buildings. Upgrading to the latest technology available in building products gives a high return for the investment. The figure below shows a return of 82% energy saving by the application of four of the most efficient building items.
Figure 2
The walls, foundation, roof, and windows of a building join the exterior environment with the interior environment in complex ways (see Figure 3). The insulating properties of the building envelope and construction quality together control the way heat and moisture flows into or out of the building. The color of the building envelope and other optical properties govern how solar energy is reflected and how thermal energy (heat) is radiated from the building. Windows bring sunlight and the sun’s energy into the building. About 50% of the heating load in residential buildings and 60% in commercial buildings result from flows through walls, foundations, and the roof.
Virtually the entire commercial cooling load comes from energy entering through the windows (i.e., solar heat gain). The bulk of residential cooling requirements result from window heat gains, although infiltration also has a significant role. Future cooling may be a larger share of total demand since U.S. regions with high population growth are largely in warmer climates.
Figure 3
Conclusion
The application of energy modeling within the design process results in well-designed buildings, systems, and control strategies which can improve comfort levels, increase reliability, and reduce costs by optimizing use of component technologies. Often these low-energy buildings can be built with little or no extra cost.
Advanced software that models buildings as integrated systems provides a powerful set of tools for ensuring effective building design and operations. These systems can predict building energy use given a description of its geometry, construction, systems, operations, occupancy, and local weather conditions.
Unfortunately, only 55% of current building projects used energy modeling anywhere in the design process, including use for either code compliance or green certification after the design had been finalized. Vee Technologies has the expertise to best serve your needs in all aspects of energy modeling.
Source:
Figure 1. https://rmi.org/wp-content/uploads/2017/05/Building-Energy-Modeling-for-Owners-and-Managers-2013.pdf
Figure 2. https://www.energy.gov/sites/prod/files/2017/03/f34/qtr-2015-chapter5.pdf
Figure 3. https://www.energy.gov/sites/prod/files/2017/03/f34/qtr-2015-chapter5.pdf
