Solar Energy Tutorial
Renewable energy (solar energy) is the cleanest, most abundant renewable energy source available.
The U.S. has some of the world’s richest solar resources.
Today’s technology allows us to harness this resource in several ways,
giving the public and commercial entities flexible ways to employ both the light and heat of the sun.
Frequently Asked Questions
This page is designed to:
❶ Explain how solar systems work.
❷ How homeowners, business owners, and mankind directly and indirectly benefit every time a solar energy system is purchased or leased.
❸ Provide you with the information pursuant to the most popular means in which Americans are obtaining solar energy systems nationwide.
The “grid” is the electrical connection of wires between an electrical utility’s generators and the customer’s electric meter. The grid also includes electric wire connections with other utilities. There are two types of definitions to be concerned with: “On the grid” and “Off the grid”. “On-grid” is when your house is connected through your electric meter to the grid. When you are On-grid, you receive electric power from the grid to serve all your electric needs. You can generate none, some, or all of the electricity you need while connected to the grid. There are restrictions on how you can generate electricity when you are On-grid. Obviously then, “Off-grid” is when your house is not connected to the grid. When you are Off-grid, you have to generate all of the electricity you need by some other means; such as gas generators or solar panels.
The process by which electricity is produced by sunlight shining on certain materials called semiconductors; such as selenium. A PV module can be used to power anything from small electronic items such as calculators and road signs up to homes and large commercial buildings.
Photovoltaic material constructed with wires attached to it so that the electricity generated when light shines on it can be used. Solar cells contain no moving parts and generally last thirty years or more with minimal maintenance.
An array of solar cells connected together and mounted in a rigid frame so that it can be installed on a roof or other flat surface.
The mounting of solar panels to metal bars which are themselves attached to one’s roof or other structure. This construction method gives the panel array a rigidity they need to be connected to the inverters and to prevent wind damage to other objects.
Solar panels produce direct (DC) current while your house uses alternating (AC) current. Simply speaking, these are two different forms of electricity. Therefore, the inverter, which is directly connected to the solar panels, is needed to convert the DC electricity coming from the solar panel to AC electricity so that it can be used by the house or grid.
Because most electric utilities are required to accept electricity from you when your solar panels generate more electricity than you need at the time, a special electric meter is used that can measure both the amount of electricity going to the grid (local electric company you are connected to) and the amount of electricity coming to you when you are not generating all the electricity you need. Both of these meter readings are read, usually monthly, and the amount of electricity you sent to the grid is subtracted from the amount of electricity that came to you from the grid. If more came to you, you pay the electric company. If more went to the grid, that amount is credited towards your next month’s bill and you pay nothing.
Photons strike and ionize semiconductor material on the solar panel, causing outer electrons in the atom to break free of their atomic bonds. Due to the semiconductor structure, the electrons are forced in one direction creating a flow of electrical current. Solar cells are not 100% efficient in crystalline solar cells, in part because only certain light within the spectrum can be absorbed. Some of the light spectrum is reflected, some is too weak to create electricity and some creates heat energy instead of electricity.
Rapidly falling prices have made solar more affordable than ever. The average price of a completed PV system has dropped by fifty-nine percent over the last decade.
The cost of PV has dropped dramatically as the industry has scaled up manufacturing and incrementally improved the technology with new materials. Installation cost have come down too with more experience and trained installers. Globally, the U.S. has the third largest market for PV installations, and is continuing to rapidly grow.
The simple answer is No. The reason is, solar panels need light (preferably sunlight because it is brighter and free) to generate electricity. Viewing the 5 minute video “How Solar Panels Work” on the Solar Energy Tutorial page of this website may be of interest to you in understanding more about solar panels.
You can only store the energy you do not need at the time it was generated. For example; at some point in time, your solar panels generate 6 kilowatts (KW) and you only need 4 KW, the extra 2 KW can be stored. On the other hand, if your solar panels only generated 3 KW (on a cloudy day) and you still needed 4 KW, you would use all of the 3 KW and you would get the other 1 KW from your electric company through your electric meter. In this case, there would be no extra generation to be stored.
Extra energy generate by solar panels can be stored in 2 different ways.
- In batteries.
Batteries can only store a limited amount of electricity based on the size of the battery or total number of batteries you have. When the batteries receive all of the electricity they can hold (they are fully charged), no more electricity can be stored in them. Your batteries will be charged up first before any other extra electricity is sent to the grid.
As a side note, batteries usually are only good for a few hours up to a couple of days and are very expensive at the present time. Also, the electricity stored in your batteries can not be used for your home unless there is no electricity available from your electric company (blackout) .
- On the grid (back to your electric company).
Extra energy that is stored to the grid is available to you automatically whenever the generation from your solar panels do not generate all the energy you need and will be sent to you as you need it. Any stored energy not used this month will be rolled over to next month and will be available to you when you need it. All extra generation stored next month will be added to the rolled over amount. There is no extra charge for your stored energy that is returned to you.
Refer to the answer to the question “What is the grid?” for more information.
5 Reasons homeowners want solar energy
5 Reasons why homeowners don’t buy solar
❶ Save money
❷ No out-of-pocket expense
❸ Increases the value of your home
❹ Helps your home to sell faster.
❺ Improves the environment.
❶ It costs too much.
❷ I have no money.
❸ I need a new roof.
❹ I’m selling my house.
❺ I’m too old to get the full savings.