In this step you will create a zoning map of one floor of the building. A key simplifying strategy of the BRS compared to other building modeling tools is to define a representative building geometry and its zones. The assumptions underlying this simplification are as follows:

1. If the floorplan and the zoning sample are scaled up to the footprint of the entire building, the energy consumption will roughly match that of the full building.
2. Enough complexity and diversity can be built into the zoning sample to provide a representation of loads and demands to connected HVAC systems for the purpose of simulating complex feedback control to evaluate re-tuning measures.
3. If the BRS is used to simulate an entire building, use of a floorplan for a single floor as the framework for the zoning map is recommended. If the BRS is used to evaluate a single air handler and the zones it serves, the specific building floor area served by that air handler can be sketched out as faithfully as possible, including sections of multiple floors in the space provided.

If the BRS is used to simulate an entire building, use of a floorplan for a single floor as the framework for the zoning map is recommended. If the BRS is used to evaluate a single air handler and the zones it serves, the specific building floor area served by that air handler can be sketched out as faithfully as possible, including sections of multiple floors in the space provided.

In this step, you will select the weather station that best represents the general weather conditions at your building. A list of weather stations based on zip code is provided, and the closest weather station is selected by default.

In this step, the user will locate monthly utility billing data for any applicable meters (electricity, steam, natural gas, chilled water) and upload the monthly data into the BRS. The data is used for the calibration process and for determining the cost impact of applying re-tuning measures.

In this step, you will identify high-level details of the building, its location, the type of heating and cooling plant, and its envelope. Many of these details are very difficult to quantify, and wherever possible, defaults and qualitative designations that pertain to quantitative estimates are available.

In this step, you will enter the schedules governing the operation of airside systems. Most of the details for these schedules can be found in the BAS under the scheduling tab or feature.

In this section, you will define the heating plant in terms of the details of the heating source and high level details about the hot water loop.

This section is applicable to heating plants that use either a hot water boiler or district steam with a hot water loop conversion. This section defines the components in the hot water loop and their control.

In this section, you will define the chillers that provide the cooling source for the chilled water plant.

This section is applicable to cooling plants that use either chillers or district cooling with a hot water loop conversion. This section defines the components in the chilled water loop and their control.

In this section, you will specify the layout and control of the air delivery and conditioning system encompassing zone return air, outdoor air intake, conditioning, filtering, humidification and fans. This might encompass one of the following systems or interconnected group of systems:

• Dedicated outdoor air system only (likely with zone-level conditioning specified later)
• Single-duct air-handling unit (AHU)
• Rooftop unit (RTU) or packaged split system
• Dual-duct AHU
• Dedicated outdoor air system delivering conditioned outdoor air to the outdoor air intake of single or dual-duct air-handlers…note that the system diagram you create will show only the connection of one outdoor air system to one air-handler, but in reality, there may be a split/header that sends the outdoor air to multiple air-handlers.

This is one of the most challenging modeling steps because it will likely involve intentional modeling decisions to simplify the building airside systems into a representative composite system that approximates the larger whole. In some cases this may not be possible and two instances of the BRS may be required to separately capture different kinds of predominate air-side systems.

It is recommended that the user perform a qualitative evaluation of the airside systems in the building to determine the prevalence of each type of system, and the most common setpoints and control strategies for those common systems. Ultimately, the various airside systems will have to be represented as a single system, using either the most common control strategy and setpoints, or a compromise strategy that approximates the collective operation of the airside systems in the building.

In this section, you will define the HVAC equipment and control at the zone level. This includes any zone conditioning equipment such as VAV Boxes, baseboard heaters, fan-coil/induction units, radiant heating/cooling panels, etc. Many of these components the BRS will model in a similar way. For example, if a zone has a VAV box that provides supply air, it doesn’t matter from an energy perspective whether the heating at the zone level is performed using a reheat coil in the VAV box, a baseboard heater, or a radiant heating panel (assuming in this case, each device is fed from the same hot water loop). Zone-level equipment can be defined separately for perimeter and interior zones. For example, perimeter zones can be defined with both supplemental heating and cooling coils, and interior zones with only supplemental cooling coils.

If the zone has VAV boxes (either single-duct or dual-duct), an airflow response curve needs to be defined. In the case of single-duct boxes, this entails a definition of the airflow response to the thermostat deadband mode, as well as to increases in heating and cooling demands. For dual-duct boxes, this also includes a definition of how the two airflows mix (or flip), and which stream is used for ventilation and in zone deadband.

Finally, this module involves setting the zone thermostat occupied setpoints and unoccupied setback setpoints. These setpoints can be set globally or zone-by-zone.

The Re-tuning Dashboard allows you to apply Re-tuning measure(s) in order to compare the performance of the building with the applied measure(s) to your completed baseline building model. In addition to re-tuning measures, several other common energy upgrade measures are included as options. Measures can be applied individually or in packages.

The measures are organized into different categories in terms of the Re-tuning principle (turn it off, turn it down, mitigate simultaneous heating and cooling, and reduce outdoor air/infiltration) for control measures, or as a capital project or operations and maintenance (O&M) measure. To apply a measure, simply click in the box for that measure that says “Enable Measure”. This will reveal the simulated details about the baseline building for reference on the left side as well as revealing prompts (usually as updates to those baseline details) for simulating the measure on the right side.

When you have applied as many measures as you would like, you can name the new run at the bottom of the page and hit the run button. This will create a new comparison simulation and a new column of results in the table in the Emissions and Savings Impacts module. You can come back to the Re-tuning Dashboard module as often as you need to in order to create new runs and add them to the table in Emissions and Savings Impacts. Below are a list of measures and any unique instructions associated with each:

This module allows the user to perform an in-depth evaluation of each measure, in order to better understand how the measure impacts the building and to troubleshoot any unexpected results by understanding the underlying behavior of sensors and actuator. This module serves as a virtual building automation system, allowing for the creation of various trend data plots and aggregated profiles of energy consumption, flow rates, temperatures, dampers, valves, etc.

In this step, the user will locate monthly utility billing data for any applicable meters (electricity, steam, natural gas, chilled water) and upload the monthly data into the BRS. The data is used for the calibration process and for determining the cost impact of applying re-tuning measures.

In this module, you have the option to make changes to your baseline model to better calibrate it against metered data from the building. This step is optional and up to the user’s discretion. Some models may be created to represent only a fraction of a full metered facility and calibration may not make sense in those cases. In other cases, taking all reasonable steps to adjust baseline assumptions may not result in a reasonably calibrated model. Calibration is an iterative process, in the sense that the user identifies areas in which there is a discrepancy between modeled energy consumption and metered energy consumption, makes a series of changes expected to move the model toward a more calibrated state, re-runs the model, reviews the results, and repeats the process as necessary until the model is calibrated.

Four metrics are provided to summarize to progress made towards calibration. The first two make use of baseline monthly utility billing data, and the second two make use of baseline interval metered data. Depending on the availability of data, any number of these calibration metrics may or may not be available. The four metrics are as follows:

1. Overall meter calibration: A metric comparing the total annual energy consumption in each utility from the model to the real building
2. Seasonal meter calibration: A metric comparing the total energy consumption in three 4-month seasons for each utility from the model to the real building:
   1. Winter (December through March)
   2. Summer (June through September)
   3. Shoulder ( April, May, October, November)
3. Load profile calibration: A metric comparing the average annual energy consumption hour-by-hour and day-by-day (by utility) between the model and the real building. This metric quantifies how well the daily patterns of consumption in each utility are captured properly by the model.
4. Temperature bin calibration: A metric comparing the average annual energy consumption by utility, binned by the occupancy status and the associated outdoor air temperature. This metric quantifies how well the model captures the response of each utility to changes in weather, both during occupied and unoccupied hours.