What is Solar Photovoltaic (PV) Technology?

Solar Photovoltaic (PV) technology, otherwise known as solar energy technologies, basically converts light into electricity. A single PV device is known as a solar cell and is usually small in size. Single solar cells produce only a few watts of energy. Connecting several solar cells together forms a larger unit called a solar panel or a solar module.

These larger systems produce more electricity because collectively they are able gather and convert more light energy from the sun. Typical solar panels for commercial businesses harness about 350-400 Watts of energy in the form of Direct Current (DC) electric.

Components of a Solar PV System

Solar Module/Panel

Solar cells are placed together to form solar modules, which are more commonly referred to as solar panels.

Solar Array

Solar modules/panels are placed together to form solar arrays. Arrays can be mounted in various ways to the ground, a roof, or a canopy structure.

Module Wiring

Within the array, the solar modules are connected by wiring, which is commonly referred to as “stringing.” The modules are then connected to the inverter. Different stringing configurations impact the voltage, current, and power of the solar array.

Solar Inverter

A solar inverter is a type of electrical converter that converts the variable direct current (DC) output of a PV solar panel into  alternating current (AC) that can be fed into a commercial electrical grid.

Solar Monitoring Meter

A solar monitoring meter measures the kWh production from a PV system. Solar meters collect PV yield production and local energy consumption to monitor and analyze.

Solar Weather Station

Environmental monitoring is critical to optimizing the efficiency of solar power generation. Weather stations have solar radiation and temperature sensors to help calculate efficiency and power production vs. consumption.

What is a solar photovoltaic system?

A solar PV system consists of multiple solar modules, sometimes thousands, interconnected to operate as an entire system, or solar array. The power that is harnessed from the interconnected solar panels is collected and sent back to a central inverter, or multiple inverters. The solar inverter is where the power is converted from Direct Current (DC) to Alternating Current (AC), which is more commonly used in all electrical applications. This conversion process typically results in a minor power loss of 2 to 8% and is reflected in the efficiency factor that is advertised by manufactures of solar inverters.

Solar array sizes are measured in Kilowatts (kW). A kW is 1,000 watts of electrical power. A Megawatts (MW) is 1,000,000 kW of power. How many homes can 1MW of electricity power? There are numerous inputs that go into this equation including environmental factors such as average sunshine, temperature, location and wind. The Solar Energy Industries Association (SEIA) ranks the United States by these environmental factors.

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Consumption is the other major factor to consider given the variance of electrical loads. Each state is largely driven by temperature, i.e. large air-conditioning loads in the hot and humid Southeast U.S. as compared to heating dominate markets in the Northeast U.S. These consumption factors are identified below based on a residential usage factors in each state.  

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Based on a combination of the environmental and consumption variables noted in the previous chart, the below represents the average number of homes powered by 1MW of electricity by state.
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Commercial building energy intensity will vary based on the vertical market and load demands of process applications. This factor is commonly expressed via the Energy Usage Intensity (EUI) index and is reflected below by common commercial building types.

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Case Studies