When applicable, the M&V plan should specify submetering sensor locations. Define the specific sensors, giving their location and sampling rates. In the plan, define the required energy model output and how measured data will be compared to the energy model. Also define how loads are arranged and grouped in electric panels. Mixing power, lighting, and HVAC equipment loads within individual panels is not recommended.
It is easiest to calibrate the as-built energy simulation software if submetering devices correlate with the breakdown of the energy usage in the energy model.
Whole-building calibration simulation requires information about the instruments that enable the project to monitor the categories listed in the IPMVP.
To achieve this credit under Option D, the M&V program must be able to identify specific building performance issues. A BMS, or submetering, can build this capacity into your system.
Permanent installation of water meters allows easier monitoring of water consumption and greater savings. Although this is not required for LEED, water metering for graywater and rainwater systems is generally included in M&V plans, and monitoring general water use is also worthwhile to verify projected savings.
An M&V program generally includes sensors—which measure the watts of energy draw, temperature, length of time, and other variables—and a central processor, which stores the collected information and helps building managers interpret it. Building automation systems typically include the central processor needed for M&V, but not all of the sensors or the additional programming to tally energy use and track patterns. Adding these pieces to a building automation system, however, is relatively easy.
Most M&V programs submeter individual systems such as lighting, heating, and cooling. Plug loads are not always submetered individually—it is easiest to individually submeter larger items and then subtract total plug load data from total building usage to get an estimated plug load.
Permanent submetering or a BMS is not necessary—project teams can instead choose a combination of utility analysis, spot-metering, and permanent metering. However, these other methods do not provide the detailed information that a BMS can, and may not help projects determine energy problems or understand actual energy use. An M&V plan without a BMS is rare in large, new-construction projects. Smaller, single-occupancy buildings may find that packaged energy monitors or monthly utility bills can provide helpful feedback without investment in a costly BMS.
