“To save energy, reduce HVAC loads, and increase guest comfort levels, the Hyatt Regency Houston decided to install window film in 48 southeast- and southwest-facing rooms. To measure heating and cooling savings, the hotel installed submetering to measures HVAC usage in the 48 rooms with window film, as well as in 48 southeast- and southwest-facing rooms without window film. The data from the submeters confirmed that window film installation reduced cooling energy use by 23%, and heating energy use by 25%. Without submetering, this data wouldn’t have been captured to prove that window film was a cost-effective, energy-saving investment that would provide a quick ROI.” –VistaWindow
It is important to note that there are data loggers available on the market for monitoring usage, troubleshooting and measurement/verification. A submeter tends to be more of a permanent instrument as well as costly. Additionally, submeters for electric usage require certain existing electrical wiring setup vs. data loggers, one can use a c-clamp and monitor usage of individual equipment.