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Solar PV System

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On-Grid Solar PV System

What is the difference between On-Grid and Off-Grid PV Systems?

On-grid PV systems connect a solar PV system to the electrical grid, enabling the user to obtain power from both sources. Off-grid solar PV systems are a self-contained system that relies solely upon solar energy, collecting all of its power from the sun. In some cases, an off-grid system will also harvest wind power. Both solar only and wind/solar hybrid off grid systems rely upon batteries to store excess power, so that energy is available at night when the sun is not out to actively generate solar power. These alternative energy systems using solar power are becoming more and more popular choices for those who are looking to save on energy costs, or who live in remote areas outside of the electrical grid.

What is a Solar Panel?

A solar panel, also called a solar module, a photovoltaic panel or photovoltaic module, is an assembly of connected photovoltaic cells, used as part of an energy harvesting system to use power from the sun in generating electricity.

Because each solar module or photovoltaic panel is limited in how much solar power it can convert and produce, most installations require several panels working together. A typical photovoltaic system comprises an inverter and interconnection wiring, and is usually implemented to save on energy costs by harvesting solar energy through photovoltaic cells (pv cells) for home residential and/or commercial uses.

Solar Energy Facts

Renewable energy sources such as solar power have quickly grown over the last several years from small scale environmentalist photovoltaic solar projects to mainstream sustainable sources of solar energy. This solar energy migration has been further accelerated by rising fuel costs, increasing electricity costs and environmental concerns.

Photovoltaic generation of power from solar energy has evolved considerably since its 1941 invention. The first solar cell available commercially was introduced in 1955, with just 2% efficiency at a cost of $1,785 per watt! The price per watt since then, along with solar cell efficiency, continues to improve with Monocrystalline solar cell, Polycrystalline solar cell and Amorphous solar cell technologies.

Photovoltaic Solar Panel Technology

Monocrystalline solar panels use a single ingot of crystalline silicon, delivering a higher level of efficiency over the Polycrystalline panels that use multiple smaller crystals. They are more costly; however, Monocrystalline solar panels generate more watts per square meter, particularly important where space is a concern. In addition, this higher efficiency helps monocrystalline solar panels to perform better in low light or shaded conditions. These solar panels are also better suited for higher temperature environments; however, this isn’t as critical, considering solar panel efficiency is typically measured at 25 degrees Celsius or 77 degrees Fahrenheit. In fact, higher temperatures will actually decrease the efficiency of crystalline solar panels. Typically above 50 degrees Celsius or 115 degrees Fahrenheit monocrystalline solar cells will have a reduction of 12-15% efficiency and polycrystalline solar cells will lose from 14-23% efficiency.

Polycrystalline Solar Panels

Polycrystalline solar panel efficiency continues to improve over the years. Although it hasn’t yet caught up with monocrystalline solar cells, it is a cost effective alternative for a good location with good light conditions, very little shade and favorable temperatures. In ideal settings such as this, the cost per watt of polycrystalline solar panels is better than monocrystalline solar panels.

Amorphous or Thin Film Solar Panels

Amorphous or Thin Film solar panels are typically created by vapor deposition similar to printing on a plastic backing, a process which makes amorphous solar panels cheaper to produce than crystalline solar panels. However, Amorphous solar panels are about 50% less efficient than their crystalline solar panel counterparts. Therefore, a lot of room is required in order to make amorphous solar panels a viable solution to produce solar energy; however, they are much better at tolerating high temperatures, so a desert environment makes them an ideal solution for solar energy companies.

Choosing the Right Solar Panel for Photovoltaic Solar Energy Installation

In choosing the right solar panel for photovoltaic solar energy installation, one must take into account the location’s conditions, the amount of room available for solar panels and costs. In the past, once the installation conditions were studied and the solar panels chosen, the last piece of the analysis would be to select a central inverter for an on-grid or grid tie system, or to choose a battery charger and batteries in the case of an off-grid solar electric installation. Today, many more options are available in using solar panels for generating electricity, including turning a solar panel into an ‘AC Solar Panel’ or a ‘Smart Solar Panel.’

The experts at Future Energy Solutions can help determine the best solar panels or photovoltaic modules to use, whether for on-grid or off-grid solar panel systems.