Abstract: A control system includes equipment and a controller. The equipment produces a resource by executing a first process when in a first state, and produces the resource by executing a second process when in a second state. The controller calculates a minimum second state operating time based on estimated cost savings resulting from operating in the second state relative to the first state. The minimum second state operating time is a minimum time amount that the equipment must operate in the second state for the estimated cost savings to offset cost of transitioning into the second state. The controller predicts whether the second process will be available for the minimum second state operating time during future time steps. The controller transitions the equipment from the first state to the second state in response to predicting that the second process will be available for the minimum second operating state time.

Abstract: An HVAC system for a building includes a heat exchanger configured to transfer heat from a chilled fluid circuit to a cooling tower circuit to provide cooling for a chilled fluid in the chilled fluid circuit, a cooling tower configured to remove heat from the cooling tower circuit to provide cooling for a coolant in the cooling tower circuit, one or more pumps configured to circulate the coolant between the cooling tower and the heat exchanger via the cooling tower circuit, and a free cooling controller. The controller is configured to determine an optimal flowrate of the coolant in the cooling tower circuit, determine an optimal flowrate of air through the cooling tower, and operate the one or more pumps and the cooling tower to achieve the optimal flowrate of the coolant in the cooling tower circuit and the optimal flowrate of the air through the cooling tower.

Abstract: A control system includes equipment and a controller. The equipment produces a resource by executing a first process when in a first state, and produces the resource by executing a second process when in a second state. The controller calculates a minimum second state operating time based on estimated cost savings resulting from operating in the second state relative to the first state. The minimum second state operating time is a minimum time amount that the equipment must operate in the second state for the estimated cost savings to offset cost of transitioning into the second state. The controller predicts whether the second process will be available for the minimum second state operating time during future time steps. The controller transitions the equipment from the first state to the second state in response to predicting that the second process will be available for the minimum second operating state time.

Abstract: A heating, ventilation, or air conditioning (HVAC) system for a building includes an air handling unit (AHU) and a controller. The AHU is configured to provide mechanical cooling for a cooling load in the building when operating in a mechanical cooling state and provide free cooling for the cooling load in the building when operating in a free cooling state. The controller is configured to calculate a minimum free cooling time based on an estimated cost savings resulting from operating in the free cooling state relative to operating in the mechanical cooling state and transition the AHU from operating in the mechanical cooling state to operating in the free cooling state in response to predicting that outside air temperature will be less than a free cooling temperature threshold for at least the minimum free cooling time.

Abstract: An HVAC system for a building includes a heat exchanger configured to transfer heat from a chilled fluid circuit to a cooling tower circuit to provide cooling for a chilled fluid in the chilled fluid circuit, a cooling tower configured to remove heat from the cooling tower circuit to provide cooling for a coolant in the cooling tower circuit, one or more pumps configured to circulate the coolant between the cooling tower and the heat exchanger via the cooling tower circuit, and a free cooling controller. The controller is configured to determine an optimal flowrate of the coolant in the cooling tower circuit, determine an optimal flowrate of air through the cooling tower, and operate the one or more pumps and the cooling tower to achieve the optimal flowrate of the coolant in the cooling tower circuit and the optimal flowrate of the air through the cooling tower.

Abstract: A heating, ventilation, or air conditioning (HVAC) system for a building includes an air handling unit (AHU) and a controller. The AHU is configured to provide mechanical cooling for a cooling load in the building when operating in a mechanical cooling state and provide free cooling for the cooling load in the building when operating in a free cooling state. The controller is configured to calculate a minimum free cooling time based on an estimated cost savings resulting from operating in the free cooling state relative to operating in the mechanical cooling state and transition the AHU from operating in the mechanical cooling state to operating in the free cooling state in response to predicting that outside air temperature will be less than a free cooling temperature threshold for at least the minimum free cooling time.

Abstract: A heating, ventilation, or air conditioning (HVAC) system for a building includes, a chiller, a heat exchanger separate from the chiller, and a controller. The chiller is configured to provide mechanical cooling for a cooling load in the building when the HVAC system operates in a mechanical cooling state. The heat exchanger is configured to provide free cooling for the cooling load in the building when the HVAC system operates in a free cooling state. The controller is configured to predict outside air temperature and transition the HVAC system from operating in the mechanical cooling state to operating in the free cooling state in response to a determination that the predicted outside air temperature will be less than the free cooling temperature threshold for at least the minimum free cooling time.