|Fig. 1: An array of solar photovoltaic panels are installed on the roof of a commercial building. (Source: Wikipedia Commons)|
Renewable energy, the idea of obtaining energy from non-depleting natural resources, such as sun, wind, heat and water, have been around since the beginning of man. However, the use of converting these energy sources to electricity has only been around for only a few decades. Distributed generation refers to the on-site generation of energy. Mostly, this electricity from distributed generation comes from energy systems such as small wind turbines and solar photovoltaics. [1,2] As of recently, due to being a relatively new technology on the globalized production market, solar photovoltaic is experiencing significant cost changes through technological progress and economies of scale.  Distributed photovoltaic systems offer a solution to the demand for electricity and also the margining concern for cleaner and more secure energy alternatives that cannot be depleted.
While distributed generation is not a relatively new concept, it still is a rising approaching for providing electricity to the core of the power system. Distributed energy generation mostly relies on the installation and operation of a handful of small, compact and clean electric power generating units. Even though not all distributed energy generation technologies are clean, the distributed generation market is moving towards a more sustainable, clean market that could be entirely composed of renewable energy sources within the next few decades. There are several types of distributed generation technologies, such as micro turbines, electrochemical devices (fuel cells), batteries and flywheels.  However, the most intriguing renewable outlets for distributed energy come from photovoltaic systems and wind turbines. The most influential of these two, currently, is photovoltaic, as it can provide a large amount of distributed electricity, or a small enough amount to power a single home. As shown in the Fig. 1, a common use for these panels is on the roofs of commercial buildings to power the large building and potentially the surrounding buildings, also. Although the panels shown in the figure seem relatively small individually, once they are installed they connect to form a network that generates the amount of power needed to provide electricity to the allocated buildings.
The make-up of a photovoltaic system is a cell that is usually square or round in shape, and composed of doped silicon crystal. These cells connect to each other, forming a panel and then these panels are connected to form an array to generate the amount of power required. Generally, each cell provides about 120 to 240 joules/minute, in accordance to its size. Some current applications of photovoltaics come from different space programs to provide power to satellites, equipment and different transmitters in space. More practical applications are the lighting of road signs, home lighting and heating, and road lighting.  As the sector for solar photovoltaics continues to grow, the market for renewable distributed energy distribution also continues to grow, as solar photovoltaics are an integral part of the sector. The three main growth drivers of distributed solar energy are a large amount of sunlight per year in certain areas of the world, financial incentives put in place by governmental organizations to promote the use of solar photovoltaics, and a general increase in the electricity prices year to year in certain parts of the world. [2,3]
A challenge to utility and energy system operators in the next few years will be dealing with the integration of large amounts of photovoltaic solar power to the electricity grid. The conundrum is that the amount of power generated by photovoltaic units can range greatly, from providing power to small utilities to providing power for several homes or a small community. Specifically, in climates with large amounts of sunshine, the addition of solar photovoltaics means distributed generation on a scale that the grid has never previously encountered.  These challenges will eventually result in opportunities for utility companies who attempt to create a "smart grid" that includes distributed generation from these renewable resources.
Renewable distributed energy distribution is a relatively new concept to the energy sector that can allow many opportunities for growth and sustainable practice within the sector. Solar photovoltaics, the largest component of renewable distributed energy generation, allows for a number of positives within the distribution of renewables, including a strong local and global well-being of humans, a minimum impact to the environment, along with more effective utilization of building sites and land that contains large amounts of sunlight per year.  As current energy grids become smarter and minimize electricity losses within the grid, the chance for distributed solar photovoltaic energy to flourish increases.
© Colton Hock. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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