Estimating Electricity Production
PV systems are distributed power generation system that can be either tied to the utility (grid-tied) or off the grid. Off-the-grid systems are generally smaller systems that are used to power farm watering system, small irrigation pumps, or campers, etc.
Due to lack of access to the grid, off-the-grid owners have to add storage to the systems in order to power devices and appliances at night. Grid-tied solar systems require inverters and other mechanical and electric components to convert the DC power produced by PV modules to AC power in order to run AC-based equipment such as lights, motors, household appliances, fans, etc. Most distributed systems operate without a battery due to the currently high prices of batteries, relying on the utility serving as a giant “battery."
How do I estimate electricity production?
Homeowners, small business owners, and installers use a simple online interactive tool, PVWatts Calculator, to estimate the energy production and basic value of energy from grid connected PV energy system. This is a simple calculator that generates annual electricity output by entering a location of the project, a hypothetical system capacity of certain kW, the installation characteristics such as tilt and orientation of the panels.
Figure 1. Annual electricity production from a 100 kWdc solar PV system in a location of in Gentry AR. The electricity generated is enough to power a broiler farm with 3 to 4 houses.