Economizer Agent

Economizer Agent helps in the re-tuning process and addresses some of the issues associated with RCx. RCx is known to save energy consumption , but the process used is not cost-effective. Economizer Agent and it’s diagnostics allow continuous re-tuning and problem identification which can lower the costs of RCx

Featured Diagnostics

Economizer Control AIRCx Main Diagnostic

Main Diagnostic handles all configuration management, reporting, and passing thresholds to the AHU diagnostics
Air Temperature Sensor Fault AIRCx

Checks for consistency between outdoor-air temperature and mixed-air temperature when the outdoor air damper is fully open
AHU is not Fully Economizing When It Should AIRCx

Determines whether the economizer is ON and working properly when conditions are favorable for economizing.
Economizing When It Should Not AIRCx

Determines whether the AHU is economizing when the outdoor conditions are not favorable for economizing. The AHU is considered to be in the economizer mode when the outdoor-air damper position and OAF exceed their minimum threshold values.
Excess Outdoor-air Intake AIRCx

Determines whether the AHU is introducing excess outdoor air beyond the minimum ventilation requirements when the outdoor-air damper should be at the minimum position. Conditions are not favorable for economizing, and there is no call for cooling the zones served by the unit.
Insufficient Outdoor-air Ventilation Intake AIRCx

Determines whether the AHU is providing sufficient outdoor air, and therefore the minimum ventilation requirements are met

Running Agent

The agent is an installed Volttron agent. Sample command line for configuring and installing the agent from PyPi, using the vip-identity “economizer.ahu1”:

vctl config store economizer.ahu1 config <path/to/config/file>
vctl install volttron-economizer-rcx --vip-identity economizer.ahu1 --tag economizer --start

Sample Data

Sample data for running the Economizer is included in the sample_data directory

Python Testing

Start Volttron Platform
Enable the Volttron Environment - source env/bin/activate
Run Pytest From inside the economizer agent directory - pytest tests/

Configuration Options

The following JSON configuration file shows all the options currently supported by this agent. A sample configuration is included with the agent

{
    "application": "economizer.economizer_rcx.Application",
    "device": {
        "campus": "campus",
        "building": "building",
        "unit": {
            "rtu4": {
                "subdevices": []
            }
        }
    },
    "analysis_name": "Economizer_AIRCx",
    "actuation_mode": "PASSIVE",
    "arguments": {
        "point_mapping": {
            "supply_fan_status": "FanStatus",
            "outdoor_air_temperature": "outsideairtemp",
            "return_air_temperature": "ReturnAirTemp",
            "mixed_air_temperature": "MixedAirTemp",
            "outdoor_damper_signal": "Damper",
            "cool_call": "CompressorStatus",
            "supply_fan_speed": "SupplyFanSpeed"
        },
        "device_type": "rtu",
        "data_window": 1,
        "no_required_data": 1,
        "open_damper_time": 0,
        "low_supply_fan_threshold": 20.0,
        "mat_low_threshold": 50.0,
        "mat_high_threshold": 90.0,
        "oat_low_threshold": 30.0,
        "oat_high_threshold": 100.0,
        "rat_low_threshold": 50.0,
        "rat_high_threshold": 90.0,
        "temp_difference_threshold": 4.0,
        "open_damper_threshold": 90.0,
        "oaf_temperature_threshold": 4.0,
        "cooling_enabled_threshold": 5.0,
        "minimum_damper_setpoint": 10.0,
        "desired_oaf": 10.0,
        "rated_cfm": 1000.0,
        "eer": 10.0,
        "economizer_type": "DDB",
        "temp_band": 1.0
    },
    "conversion_map": {
        ".*Temperature": "float",
        ".*Command": "float",
        ".*Signal": "float",
        "SupplyFanStatus": "int",
        "Cooling.*": "float",
        "SupplyFanSpeed": "int"
    }
}