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Simulated Occupancy

For long term monitoring in an unoccupied house setting, occupancy simulation is often needed to fully stress the house HVAC system. The uncertainty of occupant behavior and inconvenience prevent the long term monitoring from becoming common field test practices in occupied homes. Building America House Simulation Protocol (HSP) prescribes a "standard" set of hourly occupancy profiles that impose realistic, but known loads to the building systems [1]. In general, occupancy load generation can be categorized into internal heat gain generation, both sensible and latent heat loads, and domestic hot water generation.

Simulated Internal Gains

Internal gains are incurred from occupants' activities and their usage of lights, appliances, domestic hot water fixtures and miscellaneous loads. Internal gains are composed of sensible and latent heat gains. Convective electric heaters and humidifiers can be used to simulate the internal gains prescribed by the House Simulation Protocols (HSP).

Simulated Domestic Hot Water (DHW) Draw Profile

To evaluate advanced domestic hot water (DHW) systems performance, generating and implementing realistic domestic hot water draw profiles are many times required in unoccupied homes. There are different types of hot water draw profiles and controls mechanisms for testing different components of interest in the entire hot water system.



  1. Hendron, R. and Engebrecht, C. Building America House Simulation Protocols. National Renewable Energy Lab, October 2010. NREL/TP-550-49426.