How it works
ArenPro is a web-based and cloud-based building energy analysis tool developed for architects and building designers to be used early in the design process. Compared to other building simulation tools, ArenPro provides an easy, rapid, and real-time analysis process and enables the exploration and optimization of a large number of design options, helping designers make informed decisions from the beginning of the design.
Once registered and logged in, you will land on the dashboard page, which lists all your projects displayed as cards or list. For each project, you’ll find the following fields:
- Project Name
- Project ID
- Date Created
- Last Seen
Click on a project to open up a draft to finish it or a completed project to view the results. By clicking on “+New Project”, you create a new project of any type/location. For editing the basic information about the project such as the project name, click on the edit button (pen icon).
Create a Project
This window is where you enter some high-level information about your project
- Project Name: Assign a unique name to your project.
- Country: Select the country of your project. This information is used to find fuel factors and emission rates.
- Primary Building Type: this is the building’s main function that will strongly influence its design and operation and is used to determine the assumptions.
- Energy Code: You can optionally specify the energy code of the location if any is available.
- Unit: The current version of the tool supports SI units only; the next version is planned to include IP units as well.
Note: On top of the screen, you see the navigation menu where you can go through various tabs one by one and in order. The active page is highlighted as green and the grey tabs correspond to the pages that have not been started yet. You must complete all the required fields before proceeding to the next page. On the right side of some pages, you see the Help section which provides basic information needed for non-expert energy modelers.
On this page, you can search for the name or address of the project site, or/and navigate through the map by zooming and panning by holding left-click and scrolling. Once the site is found, you can left-click once and “Select the Location” to confirm the address.
ArenPro automatically looks up important information about the project for the energy analysis, including but not limited to the climate data (the most appropriate epw file), fuel factors, and emission rates.
To rotate the map and view it from different angles, hold Right-Click and scroll. If you zoom in enough, you can see some buildings in 3D.
This page enables you to draw building massing using simple and quick drawing tools. Click the pen button from the toolbox on the right to create a new floor plan within the map, and pan/rotate as necessary.
After drawing a closed polygon, a window pops up where you can define the floor height, the level it starts, and the number of levels it is duplicated. (when you have floorplans that are quite similar, it’s best to simply duplicate a story you already drew). If you have a different footprint shape on another floor, you may draw it on the map using the button, and within the pop-up windows select the floor where it starts, which is different from the other footprint shape.
The panel on the left bottom of the page displays the general information about the massing, including the total floor area, the floor area of the selected floor, and building height.
The envelope page is where the designer assigns information about the building facades including fenestration size and shading devices for eight major orientations and the roof.
- Window-to-Wall Ratio: is the primary fenestration property that is represented as the percentage of the transparent area to the whole wall area applied to each major orientation of the building. Select a percentage from 5% to 95%. degrees.
- Overhang and Fin Angle: the shading from overhangs and fins depends on the angle, latitude, orientation, and local climate. The angle is measured from the center of the glazing to the endpoint of the shading. In the current version of the tool, you can select the closest angle to 0, 30, 45, or 60 degrees.
- Curtain SRF: or Curtain Shading Reduction Factor refers to the internal or external shading device (blind or curtain). Select 1 if no shading device and 0 if completely blinded.
The neighbor page is where you define shading or context buildings that affect the microclimate around the building being designed and analyzed. The context may lock solar access and provide shade, and/or modify the path and intensity of airflow.
Create up to 10 context blocks of buildings by drawing simple box massing on the map using a polygon tool (similar to the Geometry page). You may change the height of them at any time, or delete a shading by clicking “X” next to it.
The construction page allows you to define the thermal properties of the building envelope. You may define constructions for exterior windows, exterior walls, roofs, interior walls, interior floors, and the foundation.
- U-Value: (sometimes referred to as heat transfer coefficients or thermal transmittances) are used to measure how effective elements of a building's envelope are at preventing heat from transmitting between the inside and the outside of a building. The lower the U-value of an element of a building's fabric, the more slowly heat is able to transmit through it, and so the better it performs as an insulator.
- Absorption: the absorption coefficient of a surface for solar radiation is defined as the ratio of the solar energy absorbed by the internal surfaces of the room and the solar energy entering through the surfaces.
- Emissivity: the amount of long wave infrared radiation that the building façade will emit to its surroundings. (Emissivity can be an important factor in selecting building materials. For example, glass can be given a Low-E coating to reduce heat loss to the outside. In effect, this coating increases the reflectance of long-wave infrared radiation back into the interior by reducing the emissivity of the glass. Conversely, ‘cool roofs’ benefit from high emissivity, re-radiating absorbed solar radiation to the sky to reduce overheating in the summer).
- SHGC: Solar Heat Gain Coefficient is the solar transmittance through translucent and transparent materials such as glass and the heat gain into the space they enclose during sunny conditions. Solar heat gain can be beneficial in the winter, as it reduces the need for heating, but in the summer can cause overheating. SHGC is equal to the solar heat that is transmitted through the material directly, plus the solar heat that is absorbed by the material and then re-emitted into the enclosed space.
The zone page is where you define the type of spaces designed in the building, which determines assumptions such as default internal loads, number of occupants, operating schedules, and the desired temperature.
- Setpoints: The heating & Cooling setpoint is the temperature to control the heating and cooling equipment so that it maintains the desired space temperature. For example, if the thermostat is set at 24 degrees in the summer, the device will activate the cooling system when the temperature rises above this setpoint. When the temperature drops below the set point, the cooling equipment will cycle off. The same premise would apply for the winter operation where the device would cycle the heating equipment on when the space temperature drops below setpoint and off when it rises above it. A Heating & Cooling setback is a simple strategy to help save utility costs by reducing how often your heating or cooling system operates. This is achieved by allowing the temperature to drift to a lower (heating mode) or higher (cooling mode) temperature when the space is unoccupied. Adjusting your thermostat can reduce how often your equipment runs resulting in lower utility costs. Cooling and Heating setpoint and setback default to best practice, and users may change them if needed.
- Zone Type: Assign the zone type in the building, based on area percentage. The zone type determines assumptions such as default internal loads and operating schedules. By selecting each zone, ArenPro automatically assigns default lighting power density (LPD), equipment power density (EPD), outside air requirement (OA), domestic hot water (DHW), and occupant intensity using the most commonly-used standards, such as NREL’s OpenStudio standards.
Mechanical Systems Page
One goal of ArenPro is to give architects the ability to consider the interplay between heating, ventilation, and air conditioning (HVAC) systems and the building massing and passive design, which typically does not occur until schematic design. Often there is a strong relationship between the HVAC system chosen and the passive design elements of the building envelope, so HVAC should be considered when evaluating building form and passive design features. Doing so in many instances can change the nature of the design guidance the simulation outputs provide.
- HVAC System: On the Mechanical System Page, the user can select an HVAC type option from a drop-down menu, listing more than 30 HVAC systems. By selecting an option, the default values for the rest of the fields such as ventilation system, heat recovery, exhaust air, and heating-cooling coefficients are selected. You can select any other option that represents your system better.
- Management and Control System: Building energy management systems (BEMS) are an information technology-based solution that uses sensing, control, and automation hardware to deliver automated and manual improvements to system operations and energy efficiency in buildings. These improvements reduce energy consumption in buildings, which usually leads to a decrease in GHG emissions. You can select from the BEMS and lighting control options available.
- Primary Energy Sources: Electricity and natural gas are the most common energy sources used in buildings. There might be other sources such as coil and oil. Select from the list of sources for heating, cooling, and domestic hot water.
The renewable page is where you specify if, and to what extent, you might use one of the following as a source of renewable energies onsite.
- Photovoltaic System: Solar energy is the sun’s radiation that reaches Earth. When sunlight hits the photovoltaic (PV) cells inside solar panels, these cells transform the sun’s radiation into electricity. To estimate the amount of electricity generation through the PV panel, specify the solar panel's area, orientation, angle, and efficiency of the module. The PV generation calculations in this version of ArenPro are overestimated as we don’t consider the effect of shadows by surrounding structures. In the next versions, we enable users to select the surfaces used for PV and consider the effect of context on that.
- Solar Hot Water: Solar water heating can be a cost-effective way to generate hot water from solar radiation. The system includes storage tanks and solar collectors. Similar to PV panels, you can maximize the use of solar panels by specifying the solar collectors' area, orientation, angle, and efficiency.
- Wind Turbine: Wind is technically a kinetic (motion-based) form of energy and wind turbines capture this energy. When the wind blows over the turbine’s blades, its generator converts the energy of the rotating blade into mechanical power, which can then be converted into power to pump water, grind grain, or provide electricity to buildings. Note that the enormous power-generating capacity of wind turbines doesn’t make wind energy feasible for your project. Wind turbines take up a lot of space and can hurt wildlife. They aren’t suitable for densely populated areas, which means they’re mostly located in rural regions, far from the cities that are most in need of their power. If your project's location has the potential for this renewable source, specify the turbine diameter and efficiency.