How to Take a Meter Reading
Your solar meter measures the total amount of electricity your photovoltaic, or solar electric, system has generated since it was installed. It will continue to measure your system's output for as long as your array is functioning. Unlike your utility meter, your solar meter does not measure how much energy your home or business uses, nor does it indicate whether the electricity being generated is being used on-site or going to the grid. Its sole purpose is to tell you how much power has been produced by your solar electric system.
The basic unit used to measure electric power is the watt. One thousand watts are called a kilowatt (kW). Electric utilities measure your power consumption over time in terms of kilowatt hours (kWh). For example, if you use a 1,000 watt hair dryer for one hour, you will consume one kilowatt hour of energy.
1,000 watts = 1 kilowatt
1 kilowatt x 1 hour = 1 kilowatt hour
The meter is a clock-like device driven by the electricity moving through it. As your solar electric system generates power, electrical current travels through the meter where it is measured and recorded over time in kilowatt hours. The more power that is produced by your system, the larger the electrical current and the more kilowatt hours recorded on the meter.
While most solar meters installed today have digital displays, there are some dial-style analog meters still being installed. These meters operate similarly, but the digital variety has the ability to display other information in addition to the cumulative kilowatt hour, including the date, time of measurement and meter errors. These additional display modes are identified by a two digit code in the upper left-hand corner of the display. If you think your meter is displaying something other than kilowatt hours, please refer to the owner's manual.
The examples above show how a meter reading of 3,946 kWh might be displayed on your digital or analog meter.
Please Note: Be sure you are not taking your reading from your inverter or utility meter. The utility meter will be labeled with the name of your electrical provider and look similar to the picture above.