Santee Electric Cooperative is your source for Solar Photovoltaic (PV) information! We are here to help our members who are interested in considering Solar PV systems become more knowledgeable and make informed decisions. For more information on Solar PV, visit MySCSolar.
Before you install a Solar PV system for your home, it is important that you de everything you can to improve the current energy efficiency of your home. The biggest way to save is built right into our rate structure, by reducing energy use during the peak hours, you will save!
With technological improvements and lower prices, solar PV is becoming more accessible for the homeowner. However, there are still issues to consider to ensure that solar PV is the right option for you.
Solar produces energy during daylight hours only. So, to use this energy it is important to know when your home uses the most energy. If your home is occupied during daytime hours and electricity use is significant during that time, you can get good value from solar panels. However, if your home is not mostly unoccupied during daytime hours, you may get less benefit from a solar system.
Most solar PV systems are installed on new or existing roofs. However, they can be ground or pole mounted as well.
To maximize annual production, it's important that the roof be oriented toward the south. Those that aren't facing south have less direct sun exposure. With today's internet capabilities, you can get an idea of the sun's patterns by viewing your own home on internet mapping applications or any other GIS-based mapping website (e.g. Google Maps).
Is your roof over 5 years old? It is crucial that the structural condition of the roof and shingles be evaluated before PV panels are installed. A PV system may be in place for 20 plus years.
It only takes a small amount of shading to significantly reduce a PV array's output. Ideally, a system should have no shade for at least 6 hours a day, preferably between 9:00 a.m. and 3:00 p.m.
The annual path of the sun should also be considered in determining if shading will impact the system especially during the winter months when the sun is at a lower angle.
The tilt of your solar PV panel is as important as the orientation. The standard practice is for the tilt angle to be equal to the latitude, which in South Carolina is between 32 and 35 degrees.
The angle of tilt of the panel from the ground should change when the season change so your panels produce the most energy. If you install panels that are flatter, you will see more production in the summer days and less in the winter days. Your ability to change this may be determined mostly by the pitch of your roof.
Before you get too far along with your solar PV system research, it is crucial that you check with your Homeowners Association (HOA) or Architectural Review Board (ARB) to make sure that an installation of solar PV system is allowed on the roof of your house, or mounted in your yard. Some subdivisions have strict restrictions dealing with additions to houses. Check your covenants to make sure.
Solar PV Contractor
Finding the right solar PV contractor is critical. Santee Electric Cooperative Does Not recommend a specific solar PV system type or installer. However we do advise obtaining a solar PV contractor that is experienced and certified by NABCEP (North American Board of Certified Energy Practitioners) in South Carolina.
Your contractor should handle most of the steps necessary to install your solar PV system and connect it to Santee Electric Cooperative's electric grid. However, as a homeowner it is prudent that you take an active role. Understanding the key steps that need to be done will help you communicate with your contractor more effectively.
There are a number of things a contractor should do:
• Help you select and install the most productive generating system for your home
• Work with Santee Electric Cooperative to ensure your system is properly interconnected to the grid
• Obtain all necessary permits from state, city, county, HOAs/ARBs, etc.
• Provide warranty information
• Set-up a repair and maintenance schedule
It is suggested that you request bids from at least 3 solar PV contractors. There are two important figures that a contractor should give you:
1) The amount of electricity the system will produce
2) The installed cost of the system per watt
Some questions that you may want to ask:
o Do you have a valid contractor's license?
o Do you have credible references?
o How long have you been installing solar PV systems?
o Have you installed solar PV systems in my area/neighborhood?
o Do you have manufacturer or other training for the type of system you will install?
o Does the installation contract clearly state what is included and what is not included in the price?
o Do you have insurance?
o Do you offer a warranty for equipment and workmanship?
Do Your Math click here
In order to determine what an investment in solar can do for you, you need to know:
• Your cost to install,
• How much electricity you will save,
• And the payback of the system.
Contact Your Utility
Since you are connected to Santee Electric Cooperative, you are required to let them know that you are connecting a solar installation (Interconnection Agreement.) You will also want to discuss your plans with your cooperative representative, so that he or she can provide information to you that you will need.
There are several good reasons why you will want to speak with your Santee Electric Cooperative representative:
• They know what you need to interconnect your solar panels to the grid
• You may need some information or history on your electric usage which they can provide
• They will have experience from working with other member-owners who have gone through the interconnection process and this may simplify it for you.
It is important to realize that your solar panels will generate electricity whenever there is any sunlight, and that there is a potential for power line workers to receive an electric shock. There are standards for the equipment you will be installing which help protect the workers, and the required paperwork and inspections are to make certain that you and your installer have a proper installation.
Below is a checklist of what must be done to interconnect. To further assist you, your cooperative representative will go over and discuss this list with you.
o Interconnection application
o Application fee
o Provide the required electrical drawing
o Provide a signed interconnection agreement
o Install the required disconnect
o Provide the necessary insurance documentation*
Sizing Your System
Sizing your system correctly so that it provides the optimum return on your investment requires a closer look at:
• Your patterns of electric usage
• What the panels will generate when they are placed in the orientation on your home
Oversizing your system means you will send more excess electricity onto the grid. Payment or credit for this electricity is determined by Santee Electric Cooperative and the laws and policies it must follow. Under sizing your system could mean that you pay a lot for a relatively smaller system when you could increase the size for just a little more cost and get extra benefit.
The best way to approach this is to look at how much electricity you use each month, and how much electricity the solar installation will produce each month. Remember that your use and production go up and down during each day and think about how much solar electricity you will really be able to use. Your installer and Santee Electric Cooperative representative may be able to answer questions about what is best for your situation.
Financing and Tax Incentive Considerations
You may be paying for your own system at the time of installation, and looking to be paid back in savings on your electric bill. There are other financing options, such as leasing the system or borrowing the money to pay for the project. There are also incentives available, such as tax credits, which can make the project more favorable to you. You will want to look at both South Carolina and Federal incentives. The Database of State Incentives for Renewables and Energy Efficiency (DSIRE) is one database that tracks these incentives. Additionally, the South Carolina Energy Office is a good source of information.
Estimate Costs and Savings
There are some tools available to help you calculate how much electricity you will produce, and what you can save. Calculator
Notify your utility if you make major change(s) to your solar PV system especially size or insurance.
*This insurance needs to be kept in place as long as the system is connected.
Ready, Set, GO!
Congratulations!!! You've done your research and are ready to install your solar PV system to your house. To make the process as effortless as possible, and to make sure that the installation is done properly, below is a final checklist of questions to ask of your installer and/or others.
- Has my installer provided me copies of all required permits? (state, city, county, local, etc.)
- What building code requirements is my installer following?
- Has my installer met the fire safety code and discussed with me?
- What insurance is needed?
- Have I provided liability for the interconnection?
- Do I need additional homeowner's insurance?
- Will I be able to monitor the output of the solar? (You will probably want to track the output to see how the system is working. There are many Data Acquisition Systems (DAS) available that will allow you to see this data via internet link)
- Has installer provided the warranties on the pieces of equipment and installation? (e.g., the panels, the inverter, the workmanship, etc.)
- Do I know who to contact to fix problems, make repairs or replacements?
- Does my Cooperative have all the information and documents needed to interconnect my solar PV system?
Maintaining your System
As is the case with all appliances, your solar PV system will require some maintenance over its lifetime. Solar PV systems are very durable and can usually last up to 20 plus years. However, the general consensus is to check your panels every 1 to 2 years or whenever you notice a significant drop in production on a clear sunny day.
Some simple maintenance tips:
- Check to see if panels are cracked or stained?
- Check to see if leaves are on or under the panels?
- Check to see if panels are being shaded by tree growth?
- Check to see if panels are dirty?
Dirty solar PV panels can significantly reduce the amount of energy your home system can generate. Dirt can come from dust or soot from nearby roads or from rainy or dry weather conditions.
If you are adding a solar PV system to an existing home, be sure to check your homeowners' insurance policy. Since you are adding to your home, you may need to make a change to your policy. It is advisable that you contact your homeowners' insurance company when you're first starting the solar process.
Homeowners should ensure that equipment and workmanship are covered under appropriate warranties. There are several warranty components to your solar PV system including:
- Workmanship-Labor warranty provided by the installer to protect the homeowner against defective workmanship …
- PV Panel-Product workmanship and materials, plus a minimum performance/production warranty of 20 years …
- Racking Equipment-Check with your installer to discuss details.
- Changes- Notify your utility if you make major change(s) to your solar PV system especially size or insurance.
Array - A group of solar panels collectively makes up a solar array.
Grid - The network of power-lines which connects power plants to substations and on to distribution lines which take power to homes or businesses. It can be used to refer to a transmission-level grid or a distribution-level grid, which have slightly different functions.
Grid-tied (or grid-connected) system - A solar electric system in which the array can receive power from the electric utility, and can also supply power to the grid.
Insolation - The amount of sunlight reaching an area, usually expressed in Watt hours per square meter per day.
Interconnection Application - The form which your electric cooperative representative will ask you to complete. This form initiates the process of connecting your solar PV system to the grid.
Interconnection Agreement - The document which defines the terms and conditions under which your system will be connected to the utility grid, including the technical requirements necessary to ensure safety and power quality.
Inverter - A device that converts DC power captured by the photovoltaic cells on solar panels into AC power that can be used to power your home or business. This device is an integral part of a solar system. Large solar systems may have more than one inverter.
Irradiance - The solar power incident on a surface, usually expressed in kilowatts per square meter. Irradiance multiplied by time gives insolation.
kW (kilowatt) - A measurement of power. A kilowatt is one thousand Watts. The size of a solar system is often measured in kW. A typical size solar system for a home is 3-7 kW; for a medium sized business is 10-100 kW.
kWh (kilowatt-hour) - A measurement of energy consumption or energy generation. One kilowatt hour is defined as the amount of energy consumed by a 1000-Watt appliance running continuously for 1 hour. This is the measurement your utility company uses to calculate your electric bill and will be the measure of your solar system's output.
Meter - An electricity meter or energy meter is a device that measures the amount of electric energy consumed by a residence, business, or an electrically powered device.
Module - An encapsulated panel containing a number of electrically connected PV cells.
Net-metering of solar electricity generation is used to calculate the difference between energy that is used and energy that is produced. The customer is then billed for the electricity he uses, or receives a credit if excess electricity is produced by the solar electric system owned by the customer.
Orientation - Position with respect to the directions of north, south, east, west.
Panel - A group of modules arranged and attached in one plane, or can be used interchangeably with "module".
Photovoltaic (PV) - The process of converting light into electrical energy. A photovoltaic cell is a device which converts light into electrical energy. The PV cells are manufactured into a module, which is then wired into an array, and ultimately into a PV system.
Pyranometer - An instrument used for measuring solar irradiance.
Racking - Structural supports used to hold the modules in place. Racking is used to mount the modules on the roof, the ground or as a panel on top of a pole.
Rated output of a module - The DC power output of a module under standard test conditions, (the module is at 25 degrees C and 1000 W/sq.m. of solar irradiance, and typically ranges from 100 to 340 watts). It is important to note that the actual operating conditions will usually be different from the standard test conditions. 1000 W/sq.m. can be thought of as the solar intensity of a clear sunny day. If the temperature of the panel is more than 25 degrees C (77F) it will reduce the output that you get from the panels, or if the panel is colder, the DC output can actually be higher than "rated".
Tilt (or tilt angle) - The angle of inclination of a solar panel or solar module measured from the horizontal (plane of the ground).
Watt - see kilowatt.
The Interconnection Standard contains the requirements, in addition to applicable tariffs and service regulations, for parallel interconnection of Member owned small generation systems and energy storage technologies (collectively sometimes hereinafter referred to as "Distributed Resources") which are rated at less than 2 MVA. Distributed Resources meeting the criteria and conditions included and/or referenced herein will normally be approved for interconnection except in extenuating site specific circumstances.