The sun’s out, the days are long…a good time to talk solar power. We’ve all seen them—the panels on the roof or in the backyard, but how do they work? What do they do?
In a nutshell—when the sun’s light hits something it creates heat; think sitting in a beach chair wishing you had an ice-cold drink. Solar heat collectors—usually large, shallow, roof-mounted boxes with black interiors and glass-covered tops—can be used to capture that heat for heating and hotwater. But sunlight can also be harnessed to produce electricity thanks to photovoltaic cells in solar panels. Now the sunlight’s energy doesn’t turn into heat, it turns into electrical current. Here’s how:
The solar panel is made up of crystals. The atoms in the crystals are all bound together by electrons. When the sunlight hits the crystals the photons (particles of sunlight) excite the electrons in the crystals allowing them to move freely, thereby creating a direct current (DC) of electricity. That current flows out of the solar panel into an inverter, which changes it into an alternating current (AC). This AC power can then be used in three ways: it can go directly to the appliances in a house to be consumed; it can be stored in a battery for later use; it can be fed into the grid.
Solar power on private properties can be either tied to the grid or off-grid.
In the grid-related option the property will use the electricity it requires and then feed back any excess into the grid. When the solar system is not producing electricity the property will get what it needs from the grid.
In an off-grid system a rechargeable battery is situated right after the inverter. Here, the excess electricity is stored until it is needed. The property will therefore keep and use only its own electricity and is considered self-contained.
What are the advantages? Once the system is installed and paid for the electricity is free, is not subject to cost variations, and is a clean, environmentally friendly alternative to fossil fuels. And it doesn’t matter if the sun doesn’t shine all day every day, you can still tap into your own reserves or the grid if you need to.
There are also some great incentives available right now in New Hampshire through the NH Public Utilities Commission for both commercial and residential properties. For example, if you’re fitting a new solar water heating system in your home you could get a rebate of between $1500 and $1900. For more information go to http://www.puc.state.nh.us/.
And if you want to know more about solar power and if it would be right for you go to: solar-new-hampshire.org. [link to: http://www.solar-new-hampshire.org/]
Sources: solar-new-hampshire.org; gosolarcalifornia.ca.gov; ucs.usa.org; howstuffworks.com; greenenergytimes.org