Most people are confused by the difference between power (rate of energy of use) and energy (total energy use in period). Because BMON is a tool that shows sensor values at particular points in time, power values should be displayed in BMON.
For electrical power, the units are kilowatts (kW) or Watts (W), which indicate the rate at which electrical energy is being used (energy used per second) at a particular point in time. If you then want to know how much total energy is used over a period of time like a day or a month, you need to do a calculation outside of BMON. You would first use BMON to determine the average power (average kW or W) for the day or month, and then multiply by the total hours in that period. BMON makes it easy to determine average Power in certain intervals like hours, days, weeks, or months by selecting the
Plot Sensor Values over Time Graph/Report and using the
Data Averaging dropdown with appropriate time interval.
For example, you have a Power Transducer configured in BMON that reads the electric power consumed by a building at any point in time. Let’s say you want to know how many kilowatt-hours of energy are used by the building in a particular month. Pull up the
Plot Sensor Values over Time graph in BMON, and then select
1 month in the
Data Averaging dropdown. Then select a long enough
Time Period to encompass the month you are interested in. Read off the average Power value for the month of interest, for example 45.3 kW for the month of April, and then multiply by the hours in the month to get total kilowatt-hours (kWh) of energy use. For this example, 45.3 kW x 30 day x 24 hours/day = 32,616 kWh of electrical energy use for the month of April.