This month we have begun setting up the UTest House. The UTest House is a 1300 square feet manufactured home at the University of Texas’s Pickle Research Campus. This test house is equipped with materials needed to monitor power use (W) and energy consumption (kWh), and understand how varying amounts of refrigerant in the HVAC unit, and air flow restrictions of the condenser HVAC unit change the performance of the system.
X10s are plugged into outlets, and are controlled through commands sent through electrical wiring. The X10s allow us to turn lamps and other electronics on and off through a remotely accessible computer. This allows us to control these amount of heat and moisture generated during different times of the day so that we can accurately recreate the amount of heat (sensible loads) created at different time of the day from people and other heat generating sources (e.g. appliances and electronics) . For instance, during the night, the amount of heat increases because occupants return from their jobs. Now that we understand these patterns, we are programming the test house to reflect this.
In addition to producing heat, occupants also produce moisture. To recreate this in the test house, humidifiers will beused. The amount of water evaporated was measured to determine how much moisture was released into the air. In our initial attempts, too much moisture was being released. The amount of heat and moisture we want to create is based on an algorithm, which determined the number of occupants in a home based on the number of bedroom in a home; the UTest House has three.
According to the Building Simulation Protocol by National Renewable Energy Laboratory, we should expect to see 220 Btu/person/h produced in sensible loads. Sensible Loads refers to temperature and can be detected using a typical thermometer. We should also expect to see 164 Btu/person/h in latent loads. Latent heat cannot be detected using a typical thermometer. Latent heat refers to changes in the moisture in the building, but does not result in changes in temperature.
Setting up the UTest House is in progress. Repairs to the weather station, which will measure wind speed and direction, temperature, humidity, and sunlight, will be needed before we can start testing. We will begin testing and measuring the power used by the HVAC unit shortly. Using CT collars, the current and voltage of the HVAC unit will be measured. This will be used to calculate the power required to run the unit.
Once testing is successful and complete, we will compare our experimental results with the results predicted by energy modeling software. The goal is to create an algorithm that will show if there is a fault in the HVAC system.