Solar Power Return on Investment

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Solar Power Return on Investment

 

For all of the investments we make in life, there is always an ROI, or return on investment. This is also true of solar electricity, which uses solar technology. The ROI in solar electricity stems from energy conservation and the level of the system’s efficiency.  For example, a small PV (photovoltaic) system can handle all of your electricity requirements as long as energy is conserved or used in the most efficient way, such as by switching off power when light is not required or when an appliance is not in use.

There are differences as well as similarities among the three solar electric systems: grid-tied, off-grid, and hybrid grid-tied battery back-up. The fundamentals in all of these solar electric systems, however, are the same. Each has a PV module or panel which can generate between 150 and 250 watts in a 3x5-foot frame that has been placed on an inch-deep aluminum frame. These modules together form the PV array, which generates the total power output in DC wattage.

PV panels need to be set firmly in place as they are lightweight; hence, racks form the best option for holding the PV panels in place on the roof. On the ground, racks can be mounted on poles or piers.

A roof mount is the most common preferred option, as long as there is no obstruction to receiving sunlight on your roof. It must be noted that a north-facing roof will not serve the purpose of gathering solar energy. For whichever type of mount preferred, roof or ground, its main function must be met: to catch optimum sunlight. In order to do this, the panels must be kept perpendicular to the rays. Some people prefer tracking mounts for this purpose. However, the primary factor in generating energy derived from sunlight remains the PV modules.

Direct Current, or DC, is generated from your PV modules, whereas Alternating Current, or AC, comes from the grid in the form of sine waves.  Electric power that is generated and transmitted today is a result of the tussle that took place between Tesla and Edison, over AC and DC, respectively, way back in the time when big energy was forming.  Edison was in favor of DC current to transmit electricity over the power lines, but Tesla preferred AC current which was cheaper and easier to convert between low and high voltages. With a strong financial backing, Tesla won the battle to have AC current transmitted over power lines. Hence, in our homes today, PV-generated DC electricity requires an inverter to convert it to AC electricity. Fuses, breakers and disconnect switches are included in the total electrical system to ensure safety during the conversion.

Each home requires an AC main service panel that contains copper-wired conductor circuits to transmit the electrical current to all parts of the home. Each circuit has a circuit breaker to ensure safety.  A solar home with an AC panel can be connected to the grid, or it can function as a stand-alone system, servicing loads in the home.

Grid-tied,