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Is Solar Power Worth It?
Is Solar Power Worth It?

In a word, yes. Solar power is great for people who are green friendly, but there is an added benefit to using solar power. Solar power saves on energy bills, making it an economically intelligent alternative. An initial step that homeowners can make is to install solar panels for electrical devices around the home. One electrical device that is frequently available with solar power options is the electric gate opener.

How does a solar panel turn light into usable electricity for an driveway gate opener? Most solar energy turns into heat, but solar cells turn the energy into electrical energy (Locke 3). Solar panels are constructed of semiconductor material, most often silicon (Aldous 5). Energy is created on an atomic level. Atoms of silicon have only four electrons in their outer shell; atomic laws dictate that a balance is created with eight electrons, so silicon atoms group together in fours to share electrons (Aldous 7). In doing this, however, pure silicon is not a great semiconductor, since the electrons can't move about (Aldous 8). Instead, solar cells use silicon crystals with impurities to create extra or missing electrons as appropriate (Aldous 9). The missing and extra electrons automatically create an electrical field as extra electrons try to move to fill in the "gaps" (Aldous 12). The electrical field is essential to supplying the energy needed to power the electric gate opener; it forces the electrons to flow in one direction, which allows the current to be utilized by attaching metal to the top and bottom of the semi-conductor (Aldous 5). When light photons strike the semiconductor, it excites the electrons even more and the extra electrons can't cross the electrical field. Providing the external current path with the attached metal gives the electrons a path to cross the field and gives the current needed to power the gate opener (Aldous 17). Another point to consider in designing a solar panel is that silicon is highly reflective, meaning that most sunlight reflects off of the surface and is not absorbed at an atomic level; in order to correct this, solar cells are coated with an antireflective coating to increase absorption (Aldous 18). Similarly, a metal grid is the most effective external current path since covering the top of the silicon would reduce or eliminate the sunlight striking the semiconductor (Aldous 24). All of these considerations will ensure the most efficient supply of energy to the driveway gate opener.

There is some controversy over whether or not solar power really is less expensive than traditional fossil fuels. The hardware needed to harness solar energy can be costly, but some Apollo, Mighty Mule, and GTO/PRO automatic gate openers are designed already compatible with solar panels. Once the costs versus savings are considered, the overall savings become apparent. One study that considered homes that were energy efficient (using alternative sources like solar energy) shows that consumers are overall more satisfied with alternatively powered homes than traditionally powered homes. The study, begun in April 2001, examined consumer satisfaction according to home values and consumption and cost of power versus other homes (Farhar et al. 2). In analyzing the results, it was discovered that most of the consumers didn’t purchase the homes with the perception that alternative energy sources were more efficient or inexpensive; it was the experience of owning a home with the alternative energy sources that changed the perception (Farhar et al. 4). Homes powered by alternative energy, contrary to some expectations, are competitively priced; the ones for this study sold for 9.2% less than similar homes not powered by alternative energy (Farhar et al. 3). Just as importantly, these homes had a higher resale value, showing that alternative energy is an intelligent investment for homeowners (Farhar et al. 4). While buying a new, energy efficient home, or remodeling a current home, may not be feasible for many homeowners, investing in solar power for a driveway gate opener certainly can be feasible for those same homeowners.

A final point to consider is that the federal government passed a federal investment tax credit in 2006, which covers 30% of the installation of a solar system (capped at $2,000 for residential installations). However, this tax credit expires in December 31, 2008, so now is the time to invest in any solar powered electrical devices, such as a gate closer (Sherwood 48). In May, Hawaii will require new homes built after 2010 to have solar water heaters (Sherwood 49). This shows that local government perceives the benefits of solar power. Even the US military understands the economic and environmental benefits of solar power - Nellis Air Force Base in Nevada is solar powered (Sherwood 48). The government's recognition and exploitation of solar power demonstrates one further point: solar power is reliable.

So, what's the best way to invest in a solar powered automatic gate opener? Mighty Mule and GTO/PRO both manufacture electric gate openers that are solar capable. Apollo (fittingly named after the Greek god of the sun) has specifically focused on creating driveway gate openers that are highly solar capable. Customers who already own automatic gate openers from these manufacturers may easily purchase solar panels to make their driveway gate opener solar powered. When installing a solar panel for a gate opener, experts recommend installing the cells so they face true south, if they are installed in the Northern Hemisphere. This will result in the best energy production. The panel should also be installed at an angle equal to the latitude of the location so that the most energy can be supplied to the automatic gate opener (Aldous 26). In the end, the savings will be worth the investment.

Sources:

Aldous, Scott. "How Solar Cells Work." How Stuff Works. 8 Nov. 2008 .

Farhar, B. C. and Coburn, T. C. A New Market Paradigm for Zero-Energy Homes: The Comparative San Diego Case Study, Executive Summary. December 2006: 2-6. 8 Nov. 2008 < http://www.barbarafarhar.com/resources/pdf/Special_Exec_Sum_12_20_06.pdf>.

Locke, Susannah. "How Does Solar Power Work?" Scientific American. (20 Oct. 2008). 8 Nov. 2008 .

Sherwood, Larry. "Boom Times for Solar." Solar Today September/October 2008: 48-49. 8 Nov. 2008 .