Learn How It Works


How do renewable energy power systems work?

Solar photovoltaic arrays and wind or hydro turbines convert sun or kinetic energy into direct current (DC) electricity.  DC electricity is what is stored in batteries.  Solar PV, wind, or hydro electric systems may be designed for 12 volt DC, 24 volt DC, or 48 volt DC.

To keep the electricity generated by solar, wind, or hydro available it is either stored in batteries, or excess may be fed into the grid.

Most household appliances require AC power.  To change DC electricity into AC an inverter is used to convert the 12, 24, or 48 volt DC current from the battery into 120 volt AC current, the same as standard utility power for standard household lights, outlets, and appliances. Most solar homes use primarily 120 volt AC produced by the inverter.  After conversion to AC, power the inverter connects into the circuit breaker box of the house in place of utility lines. The house breaker box routes power to lights, appliances, and outlets of the house. Inverters for home power come in ratings from 50 to 5500 watts and are sized for the maximum combined load to be sustained.

A note about Direct Current appliances -  DC appliances can be very energy efficient.  A small solar electric RV, boat, or cabin may use only DC wiring and appliances.

Commonly, a standby inverter is used in on-grid/off-grid applications.  These inverters have a built-in battery charger and transfer relay. Many will auto start a backup generator. When the input terminals of a standby inverter/charger receive power from an outside source of AC (a generator or utility power) the inverter stops producing AC power from the batteries, and instead passes generator or utility AC power straight through to the house. At the same time it uses the generator or utility power to recharge the batteries. Some standby inverters even auto-start the generator when batteries need charging. A separate battery charger can be used instead of (or in addition to) a standby inverter/charger.

When stored power is low or during a power-outage/shortage, an engine driven backup generator is used to recharge the batteries or provide direct power.  The generator is shut down after the batteries have been recharged. The backup generator produces  120 volt AC power and also serves as a 2nd source of AC power such as during a temporary need for additional power for large loads like during construction.
The US Energy Information Administration Education

Our information is to help you be thoroughly informed. 
A valuable information source is the US Energy Information Administration. Here is a starting point for understanding PhotoVoltaic function. There are additional links.


How do solar panels work? - Richard Komp

This is a TEDTalks Educational video- a portion of it. To see the entire lesson go to TED-Ed HERE
For off-grid or battery based systems the DC power is stored in deep cycle lead-acid batteries or other high-performance batteries using a charge controller which controls the flow of power to the battery. To prevent battery damage from overcharging, the charge controller automatically cuts back or stops the charge when batteries become full.  There may also be a meter  to show the status of the charging process.  Batteries will allow the user to draw power from storage, even during sunless, windless, or waterless periods.  Power can be drawn slowly by light loads or quickly by heavy loads.  The batteries can instantly supply large surges of stored electricity as needed to start or run heavy power appliances that the solar panels or hydro or wind system alone could not power. Typically, 2 to 12 square feet of batteries weighing 200 to 1000 pounds are enclosed in a battery box with a vent pipe to outside. The size of the battery bank depends on the characteristics of the system including surge power requirements and the amount of reserve power needed, because lead-acid batteries need to be frequently 100% fully charged (equalized) to remain in good condition. They should never be drawn completely down to empty. Because of these needs, to get the most years from your batteries requires some supervision/maintenance by the owner. 

Other components of a renewable energy system are fuses and circuit breakers, and meters for gauging how things are working, how much power is being generated and/or stored.


Now that you know -

You've been thinking about using renewable energy sources for quite sometime, but didn't know where to start.

Now that you get it, it's time to pull the trigger.
Become a Responsible Citizen of the Planet

Talking about changing your habits to reduce the contribution is good.

Changing the way you use the earth's resources goes further. 
Do it right the first time!

You could work with someone with less experience and get an "almost" system.

Or you can call Dana at Great Solar Works! and install the real deal.

Make the right choice the first time.