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use of solar energy and to share information
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The Four Major Components 
(This article is from Mr. Solar's March 2001 newsletter) 

There are four major components to solar electric systems; Solar Panels, Charge Controllers, Batteries and Inverters. All of these components are necessary to have a functioning Solar Electric (PV) system.

The solar panel is the basic building block of the system, this is your battery charger. If you have several solar modules wired together you have created a solar array. The size of the solar array determines the amount of power or energy that will be produced. Your location is also a factor in the amount of energy produced. If you live in Florida, Southern California, or Texas you will produce more than if you live in Oregon, Maine or Maryland. In general the closer to the equator you live your system will produce a larger amount of energy.
Do you want to know how much power can be produced in your area. Check out our FAQ question
*How much power will a solar module produce at my location?*

Charge controllers come in many different sizes and types. They all basically do the same thing. The charge controller prevents the solar panel or array from overcharging your battery. Batteries are the energy storage for your system. Without batteries there is no way to store the energy your solar panels produce during the day. Typically loads receive their power from batteries instead of directly from the output of a solar panel. A solar panel produces a high voltage that will damage electronics if loads are powered directly. A common application for solar panels directly powering a load is water pumping. Instead of storing energy you store water. This way you can pump during the day and have water all night.  Batteries will provide you with the energy you need at night.
The last major component is the Inverter. The inverter converts the DC energy stored in your batteries and turns it into the AC power you use in your home. Inverters are rated by wattage and the quality of their output. You can use a 50 watt inverter that plugs into your car 12 volt outlet to power a computer, or you could have a 4000 to 11,000 watt inverter system that powers your home.
These major components can be put together in many different ways. Minor components like wire, disconnects, circuit breakers, and fuses are also needed for a complete system. Now that you know what the major components are, let me introduce you to how these different components are used in systems**. 

-Chest freezers are 9-22% more efficient than upright models.
-Using a pressure cooker cuts energy use by 50-75%.
-Small appliances and electronics account for 14% of average household energy use.
-The averaged air-conditioned home uses more than 2000 additional kilowatt hours per year.
-In colder climates windows are responsible for 10-25% of a homes winter heat loss.

Stand Alone or "Cabin" Systems Solar:
You need---Charge Controller---Battery---Inverter---AC Loads or Solar---Charge Controller---Battery---DC Loads
A Stand Alone solar system is just as it sounds. It is not connected to the utility or other types of charging sources. This type of system is used when utility power is not present and is too costly to bring in from the nearest pole. If you have a shed set off from the house, a cabin in the mountains, or a summer home by the lake that is without power this type of system can often be very cost effective. When compared to bringing in the power lines, the initial cost can be less. Some of the pros of this type of system are: The lack of reliance on the utility, potential cost savings. Some of the cons of this type of system are: Even though there may be a cost savings over running utility line, there can be a high initial cost. You have to know your loads and have the system designed correctly since you don't have utility power for backup. ++++++++++++++++++++++++++++++++++++++++++ 
Utility Tied System Solar (grid-tie): 
You need---Inverter---Utility 
This system is the newest addition to our site. The system utilizes an inverter that does not require batteries. During the day, the power generated is fed back into the utility. If you are producing more power then you are using your meter can even spin backwards. Due to the simplicity of the system, it has the lowest cost per watt. The downfall of this system is that when the utility grid fails the system will shut down.
Battery Backup System Utility (off-grid)
You need---Battery Charger---Batteries*Inverter---AC Loads 
This is a system that does not involve solar power. This system utilizing an inverter that has a built in battery charger. It will charges batteries and hold them at 100% waiting for a power outage or a brownout. Your critical loads will never see the power outage. Computers, home health equipment, and lights will continue to operate when the utility grid fails. This is a system that is great for areas where power is lost for short periods of time. The limit on this system is the amount of battery capacity that you have. The larger the batteries the longer your run time will be. 
Utility Tied Battery Backup System with Solar (hybrid system): 
This system operates on the same principal as the Battery Backup System. The difference is the addition of solar. The solar is used to charge your battery bank. When the batteries are full the excess power is fed back into the grid. In the event of an outage, your critical loads are powered by the system, and the solar panels continue to charge the batteries. The benefit of this system is that you have the ability to sell power back and have the piece of mind that you critical loads will continue to operate. The drawback is the cost per watt is higher then a Utility Tied System.
Tips on Conservation 
Check energy guide labels on all new appliances purchased, this gives you the cost of energy used per year. Flow control faucets can reduce the heating bill by as much as $86 per year. When on vacation, turn off the hot water heater. Run only full loads in the dryer, and if possible, dry two or more loads in a row to make use of heat already in the dryer.