How Solar Energy Works ftl33301
How Solar Energy Works, PV Equipment, System Types and Science
Let’s explore How Solar Energy Works by understanding that Solar Energy is an effective way to produce your own electricity but, it can be rather complex and must be managed properly to avoid serious injury or damage. It is always best to consult with or hire a proven professionally licensed electrician for all electrical needs!
Solar Photovoltaic (called PV) Energy systems all work on the same principle – PV solar panels convert sunlight into Direct Current or Electricity (called DC Power). DC Power is very common in fact it is what is used in your flashlight, car and boat.
Solar PV Inverters “convert or invert” DC Solar power into the same Grid AC power provided by power companies like FPL. AC Electricity powers your home, farm or business.
This is shown in the diagram below:
The power we can gain from the sun in only a single hour could power the entire plant’s energy needs for an entire year. Finding ways to safely and cost effectively harness that power must be a goal for the entire human race. Continuing to burn fossil fuels at the rate it is now being burned will lead to a certain outcome: higher electricity costs, global warming, trade wars and pollution.
Solar Energy in itself is not the answer to these energy challenges but, will certainly have a growing role in powering the plant today and well into the future. We hope you enjoy this section on How Solar Works.
How Solar Works Harnessing the Power of the Sun
To harness the power of the sun we must convert the solar PV panel’s DC Power into Alternating Current (called AC) that is generated by the power company and used in all our homes and businesses.
The equipment that coverts solar panel PV DC power into common AC electricity is called an Inverter.
There are three main types of inverters on the market and we explore each of them below. They are String Line, DC Conditioned and Micro Inverters and each has specific uses, advantages and disadvantages.
We hope to provide you with the basics of solar and encourage you to watch the videos and read the reports herein before attempting to install your own solar system. Most importantly we hope to educate those who visit this site with proven information so you too can Go Solar for your home, farm or business.
How Solar Works – A Video From the US Department of Energy
Inverters are the heart of understanding How Solar Works
Inverters serve as the vital link between the DC Electricity that is generated by a PV solar system, and the Grid AC Electricity that it transmits is used throughout the world, and in each of our homes. Even though all inverters perform this same vital task, the way in which they do so varies based on the DC source from which they are drawing the electricity.
String-Line Inverters connect directly to a PV array in order to convert the DC electricity to AC, as soon as it is generated. Multiple solar panels (or modules) are connected together in strings, before they are connected to the inverter; this allows for all of the modules in that string to share the same conductor (wire), thus cutting down on the amount and size of the wire required to connect the system safely. The advantage of this inverter type is price, simplicity and high efficiency.
The primary disadvantage to this system is that if even one module in the string becomes shaded, the entire string becomes limited by the shaded module. Furthermore, since all of the modules are connected together, the inverter “sees” the string voltage equal to that single module’s, and as such reduces the performance of the string to that shaded module’s output. To learn more about how this affects system performance and so much more, come visit us at US Solar Institute today!
DC Optimized products overcome shading, and module mismatch losses that are associated with string-line inverters by installing a “power optimizer” on the back of each and every PV module. This power optimizer performs to maximize and power point track (MPPT) each module in real time, and is able to adjust the output characteristics of each optimizer to ensure that the string is producing as much power as possible, across the string as a whole.
Solar Edge is the unchallenged leader in this market, due to their outstanding product record, and understanding of the real challenges installers face. As another added advantage, since the Optimizers are tracking the power production of each module, they are able to report that production back to the inverter, which can then be forwarded on to the Solar Edge monitoring portal; Installers and customers can then view exactly how much power each module, and the system as a whole, is producing at any given time, from their computer or smart phone. Additionally, installers can set up alerts so that they are notified if a module fails or if it significantly under-performs (due to shading or physical damage).
Micro-Inverter Systems, such as the EnPhase product, consist of a small inverter, which is placed on the back of each and every module; this means that the output at the Panel level is AC, and immediately available for interconnection, without any other power conditioning equipment. The Micro-inverter systems also allow for module level MPPT, however they are not as reliable as comparable DC optimized systems. This is because these micro-inverters require that several complex power transformations are forced to happen in a small metal box, out in the hot sun and all of the elements; the excessive heat tends to lead to increased failure.
Most micro inverters are warranted for 15 years, to covers the cost of the equipment, however it does not cover, shipping, handling or the cost of labor required to climb up on the roof, remove the old inverter, and replace it.
Module level monitoring is also available from En-Phase, but it requires additional hardware, and an annual fee after the first 10 years of operation. All in all, micro-inverters are simple to design and install, and great for newcomers to the industry, very small systems or for those who do not yet understand how to design a more effective longer lasting system.
Battery based inverters draw energy from a battery bank. Batteries do not generate electricity, they simply store it for later use, so there must be a power source to replenish the electricity taken out of them; common power sources include a combination of solar power via a charge controller, a gasoline / natural gas generator, the utility grid or even another renewable energy source such as a wind turbine, or a hydroelectric generator.
Some battery based inverters have an integrated charger, and an “AC Pass-through” function. This allows an ac power source, such as the utility grid, to be connected to this input, and as long as this source is present it will directly power any loads connected to the output of the inverter, as well as simultaneously recharge the batteries; then if the utility grid should fail, and the power source is removed, the inverter will immediately begin to power the loads at it’s output, with energy that was previously stored in the batteries. Some of these inverters, such as the Outback Flex Power® line, even have the ability to push power back onto that grid input, once the batteries are completely full, allowing the PV system to further offset electrical usage.