When it comes to combating carbon dioxide emissions and climate change, one of the biggest improvements possible is installing solar panels. Solar panels help to reduce energy costs, reduce emissions, and above all improve the efficiency of one’s home. However, a solar panel installation is much more than a semiconductor sandwich, but rather a complex system designed to meet the power draw of an average home.
Obviously, the basic components of a solar panel system are the panels themselves. When making the decision, consider the size and durability of the model. For the size, the power output can vary depending on the technology (single crystal, thin film, or polycrystalline) but in general, a two square foot panel will output 50 watts, while an eight square foot panel will output 190. Durability-wise, most solar panels are framed in aluminum, allowing them to weather the efforts of nature.
The second component of a solar panel system is the inverter. An inverter converts DC to AC and is required because the power coming from the panel array is direct current (DC) while a home circuit only accepts alternating current (AC). Inverters must be judged on their automatic shutoff capacity, battery charging capabilities, and surge capacity.
An inverter actually runs off a personal battery bank to operate, and must be able to automatically turn off when the load drops so as not to drain the power source. In a similar vein, the inverter must be able to pass a portion of the panel power towards recharging the battery bank. Lastly, all appliances have a startup surge, especially noticeable in large devices such as dryers. The inverter must be able to handle this surge, multiple surges if possible.
Finally, every solar panel system utilizes a large array of batteries to store and regulate power flow to the home, but a charge controller must be in place to prevent damage from occurring. If the battery is full then “voltage regulating” begins and the power is cut-off. Look for controllers featuring maximum power point tracking or MPPT. This technology is in place to optimize panel energy production by changing charge rates at specific voltages. Also, the controller should feature battery temperature compensation or BTC. This system modifies the charge rate in relation to temperature, as the batteries are sensitive above and below 75F.
For the environmentally-concerned individual, solar panels are a great solution to combat global warming and carbon dioxide emissions. Solar panels utilize semiconductor layers to convert photons into usable electricity, and thanks to recent advances in technology, the panels are more efficient than ever before. Each panel consists of a set of photovoltaic cells and when used on a home, collects and stores energy for use and nighttime power consumption.
With any solar panel installation, the first step is to position it for maximum sunlight reception. This means having it face the south in the northern hemisphere and vice versa. In addition, try to place the unit directly under the noontime sun.
Always remove any obstructions when performing a solar panel installation. If the obstruction happens to be a tree on your property, remove limbs to clear a path for the light. If the obstruction is out of your control, the only option is to move the panel array.
The biggest factor in a solar panel installation is the mounting. Currently, three types of solar panel mounting hardware are available, and vary depending on the object the panels are placed on and the specifications of the panels themselves.
The first is known as a roof-ground mount. These are used for larger panel systems or for systems away from the city power grid. These are constructed from a grid of supports, and for this reason they tend to be ugly. In all cases, consult with the neighborhood or development director to attempt this type of installation. These units can tilt, allowing for more power production, but they can also be more expensive than a flush mount.
Flush mounts are appliances used for attaching solar panels to roofs and RVs, but they are limited to small systems only. These brackets are unable to support big arrays, and only provide a minimum clearance between two and four inches. This may be adequate for some units, but proper airflow is invaluable for a solar panel system. If the panels overheat, then the operating lifespan is significantly reduced.
Pole mounts are the last variation, but basically consist of a metal rail/rack unit that attaches to the panel. This rail/rack device is then secured to a large pole. The main problem with these units is the weight, so machinery may be required to properly seat the panel array. However, these mounts are the most efficient because they can track the sun throughout the day for maximum light absorption.
Earth 4 Electricity can be summed up in one word: “Wow!” Earth 4 Electricity has been nothing short of amazing, from the beginning to end. I think what truly made my experience memorable was the thorough instruction and explanations I was given throughout the entire process.
Earth 4 Electricity didn’t try to confuse me with complicated mumbo-jumbo, but they taught me that solar panels create electricity when “photons” hit the panel, creating an electric current. This helped me to understand how many panels I needed for my home and the average output for each. I thought I wasn’t going to be able to afford to use solar to power my home, but with Earth 4 Electricity’s cost breakdown I was so relieved to discover I could.
Before I met Earth 4 Electricity, I was contemplating a complete solar switch, but Earth 4 Electricity folks helped me on that issue as well. I now understand the difference between an “on-grid” and “off-grid” system. With an “on-grid” system, I could sell power back to the utility company! After years of my money flowing their way, it feels good to stick it to those robber barons! I was also informed that an “off-grid” system would require more batteries, more solar panels, and a backup power source. I couldn’t afford that! Thanks again for pointing me in the right direction.
When their courteous installation crew arrived at my home, I was overjoyed to see that they had taken all of the necessary precautions to avoid damaging my roof. Even better, they explained to me where exactly the panels would go: on the south-facing portion of the roof in the northern hemisphere and the north-facing portion in the southern hemisphere.
What’s the last thing Earth 4 Electricity did to help me out? They helped me find tax credits! At first I thought “No, would the government really pay me for going green?” Then, Earth 4 Electricity showed me what was already happening in other states, such as Massachusetts where owners can receive a property tax exemption and income tax credits, or in Georgia where owners can receive a $0.15 credit per kWh for 10 years.
Now that my house has been updated, I am going to recommend Earth 4 Electricity to all of my friends, family and coworkers. Earth 4 Electricity’s service could not have been better nor their work more efficient and precise.
As a popular method to go green, solar panels offer the homeowner more than a reduced carbon footprint, but a sense of independence from utility barons. However, it is important to take your energy requirements and budget into account or risk getting carried away in the project.
For many homeowners, the price is simply too great. In 2005, the average price per watt of solar panel –produced electricity ranged from $3 to $4, with an installation cost ranging from $15,000 to $20,000 per kilowatt. This high price can be attributed to the precise manufacturing process and semiconductor cost. Even though this barrier may seem difficult to surmount, the solar panels cost is continually dropping thanks to manufacturing improvements and economies of scale.
The solar panels cost may vary, but the vast majority of the cost originates in the solar panels themselves, around 70%, followed by labor, inverter, and batter y costs. It is often less expensive to install the units at the time of construction and doing so can lessen the financial shock of the project. The inverter is the second piece of the system, converting the DC power produced by the panels into AC for appliances and lighting. Also, depending on the system (off-grid or grid-tied) the owner will have to invest in a battery bank to store the excess power.
However, the solar panels cost is often offset by rebates, tax credits/exemptions, etc. In fact, the federal government offered a 30% tax credit on solar panels installed between 2006 and 2007. The benefits also operate on the state level; some states with incentive programs include Arizona, California, and Massachusetts.
Arizona offers a rebate for grid-connected systems at $4 per watt up to a maximum of $7,000. For off-grid panels, the rebate is only $2 per watt at the same maximum limit. In the state of California, the incentives can vary depending upon utility company and location, but some have offered benefits of $3.50 per watt up to a maximum of $8,000. Incentives in Massachusetts tend to operate at the state level, but include local property tax exemptions and state income tax credits. In addition, any solar, heat pump, and wind system is exempt from sales tax.
When it comes to living green, home solar panels are the premier solution. With continuously falling prices and a payback time as little as three to five years, installing a set of panels is a manageable undertaking for any homeowner.
Technology Overview
Home solar panels are also referred to as a photovoltaic system. Photovoltaic refers to the process of generating electricity from light via a semiconductor layer. What makes PV cells able to compensate for the energy demand of an average home is scale. Each panel contains approximately 10 modules, and each module contains 40 cells.
Each cell consists of four layers: a protective layer on the surface, two silicon layers, and backing. When sunlight strikes the cell, it travels through the protective layer and hits the positively-charged back layer of silicon. The photons dislodge electrons from this layer, sending them to the negatively-charged silicon above. Circuitry mounted on the top silicon intercepts the flow of electrons, thus generating electricity.
Grid vs. Off-Grid Systems
When installing home solar panels, one consideration is the grid connection. A grid-connected system has the advantage of backup power in the event of poor light conditions, but one is not completely independent from the energy company. However, grid-tied systems have the capability to “net meter” if the system is producing too much power for the demand. In this case, owners sell electricity back to the utility company in the form of credits which can later be used in months when the system underperforms.
The biggest drawback to the off-grid plan is the cost. The current average cost per kilowatt hour varies from $15,000 to $20,000, so the owner either needs to purchase enough capacity to completely run their home or invest in a hybrid system that uses a backup generator. Furthermore, an off-grid system requires an extensive battery bank to store power for nighttime and low-light use.
Installation
For home solar panels, the units are mounted depending on the hemisphere. In the northern hemisphere, the panels are mounted on south-facing roofs, and vice versa in the southern hemisphere. In certain cases, the city may allow the owner to mount the panels on a pole or mounting array for even greater reception. Lastly, the position of the panels will also depend on the homeowner’s place of residence. For example, sun-drenched Arizona will be much less discerning than upstate New York.