Green Building Energy System (proposed H-VAC system based on ASHRAE standards)

Our project was on the building of Decathlon which is located at Perugia. For this project we comprehensively analyzed the building from energy point of view and we designed the system for having the most efficient and greener building as possible.

First, We totally analyzed the location, building orientation, environmental conditions and etc, for the building for having better view on the project.

modeling of the building

In this part of project, we exactly evaluated the Map of the building with AutoCAD, while after we analyzed all the dimensions and different rooms usage, and we calculated loads and the energy consumption for heating and cooling. For reaching this object we modeled all the building with IES VE software by considering both internal and external gains after specifying the materials and different types of boundaries for each block. The Model Geometry has shown in the Figure below from top view in the AutoCAD and the front view of the roof has shown in the following Figure.

Defining Thermal Blocks in AutoCAD

For the next step of this project we started to define thermal blocks inside the AutoCAD and our blocks were based on the usage of each section, for example when rooms had same usage and thermal condition, we specified them as one thermal zone. Our separation mainly was on the different temperature of each zone, number of people working in each part, solar radiation, using of computer systems and the typology of each space. The final collection for the thermal zones has shown in Figure below:

After considering walls, windows and shadings we import the collection as a DXF file to the ISE VE. With a good approximation we consider the roof as a flat roof with combination of glass and shadings. For sake of simplicity we opted for calculating a Total Equivalent Roof Height (TERH) so that our building model has all the same height for all parts. This has been done by computing the weighted average of the ERHs, weighted on the different Area's Lengths, measured from the front view. As a result, our Total Equivalent roof height is 7.48 meter. At this point of the model we have a unique equivalent height for the building which ensures that the total volume of our model is equal to the total volume of the real building. As there is no separation between the ground-floor environment and the area just below the roof we can treat each room as a unique ambient from the floor up until the roof. Therefore, on IES VE we will be allowed to extrude all the rooms at once starting from the plan view. By using this height for the overall height of the building and considering the related height for other parts such as internal walls, windows and shading we get to this model that has shown in Figure below:

Defining Materials and Properties

Based on the data that has provided, we consider different types of boundaries and materials which we explain in the following Table . For windows we considered four type of window, because we approximated those with similar thermo-physic properties. And for internal walls we considered them same as external walls.

Space Conditions of The Building

In our model for the HVAC we used the APSYS system and the energy standard that we used for the building is ASHRAE 90.1-2010. For the number of people, lighting, the heating and cooling equipment we used standard of the ASHRAE. The seasonal energy efficiency ratio (EER) for the chillers is 2.5 and during the winter the building gets warm by using boilers with the efficiency of 89% as mentioned in the ASHRAE standard.

Results of the simulation

After modelling the system in IESVE and setting the related data for each zone, we get reasonable results for the building loads. Since the main loads for the heating part comes from the boilers load, we get this graph for all the year. The overall trend of the graphs completely follows the climate trend

PS:

• All The results and analysis extracted and done by IES-VE and AutoCAD.

• Our project score was 26 out of 30, and it was among top ranked project of course.

• More information are available upon request

• click HERE for downloading the Report.