HVAC optimization that runs each unit at the lowest energy that still meets comfort and air targets.
Optimization rules adjust ventilation, schedules and setpoints from occupancy, air quality and outdoor conditions. Aqueduct ships pre-configured strategies and a builder for your own, runs them as recommendations or as control, and measures each one against a normalized baseline.
Pre-configured strategies, your own rules, and a measured result for each.
What runs out of the box
- Demand-controlled ventilation
Ventilation targets set from CO2, with saving, boosting and override levels.
- Occupancy schedules
Detected or scheduled occupancy switches equipment between occupied and unoccupied modes.
- Load sequencing
Large loads staggered so they do not set a new peak together.
The rule builder
- Thresholds
On a device metric, or on site, floor or zone occupancy.
- If/else logic
Actions keyed to occupancy and conditions.
- Severity
Info, warning or alert, so routine changes and real problems stay apart.
What tuned ventilation and controls are worth.
cut in HVAC energy, nearly, from matching ventilation to occupancy in a PNNL model of a large office.
Source: PNNL via ScienceDailypotential cut in US commercial building energy from well-tuned controls, in a PNNL simulation.
Source: PNNL via US DOELimits
Optimization acts on equipment only where control is enabled, with owner approval; otherwise it runs as recommendations your team applies. Gains depend on how the building ran before: a site already on tight schedules has less to find.
Where strategies trade energy against each other
Optimization in one place can cost energy in another. Each strategy is judged on the energy of everything it affects, not the one machine it changes.
| Strategy | Saves | Can cost | What Aqueduct counts |
|---|---|---|---|
| Chilled water reset | Chiller compressor energy | Pump energy in variable flow plants; dehumidification | Chiller plus pump kW, space humidity |
| Condenser water reset | Chiller compressor energy | Tower fan energy and tower water | Chiller plus tower fan kW, makeup water |
| Supply air temperature reset | Cooling and reheat energy | Fan energy at higher airflow | AHU fan, chiller and reheat energy together |
| Static pressure reset | Fan energy | Comfort in starved zones if a box is faulty | Fan kW and comfort compliance per zone |
| Demand-controlled ventilation | Outdoor air conditioning energy | Air quality if sensors fail or drift | Energy with CO2 exposure in zone-hours |
| Optimal start and stop | Runtime and fan energy | A higher morning peak if every unit starts together | Runtime avoided and peak interval demand |
| Peak shaving | Demand charges | Energy if pre-cooling is excessive | Peak demand and kWh in the same period |
Sources3 references cited on this page
Related
Common questions
No. Aqueduct optimization strategies can run as recommendations that your team applies through the BMS. Switching a strategy to control is a separate owner decision made per unit, and every command is then logged. See how keeping your BMS works.
Aqueduct baselines each unit's power use before a strategy starts, then compares actual use with that normalized baseline afterwards. The difference is reported in energy and money per unit and per site. See measurement and verification.
Demand-controlled ventilation in Aqueduct sets outdoor air from measured CO2 and occupancy instead of a fixed rate. Saving, boosting and override levels let a full room get more fresh air while an empty one gets less. See CO2 monitoring.
It is a reset logic in which a setpoint is trimmed a small step at a time while no equipment is asking for more, and pushed back when enough requests arrive. ASHRAE Guideline 36 describes it for resets such as static pressure and supply air temperature.
Sequence exceptions are counted on every controlled unit, and each strategy is judged on the combined energy of everything it affects. A strategy that raises another system's energy more than it saves shows up as no saving.
See Aqueduct on your own facility.
Bring a site, a utility bill or a question. We will show you where the loss is.