In many field tests, the electrical energy use of the house as a whole or a specific component is the focus of the project. In retrofits, the goal is to decrease the energy use of the home. In new homes, there is typically an expected energy use of the house based on models. For any projects involving a novel system, like a new type of heating, ventilation, and air conditioning (HVAC) equipment or lighting system, measuring the energy use of that system alone are of interest. As new homes become more efficient, plug loads like TVs and computers become a larger part of the home's electrical usage and so those items may need to be monitored separately as well. Regardless of the intent of the field test, electrical energy will likely be measured for some purpose.