Solar panels with sun reflecting on them

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Solar Basics

Solar systems, both solar electric and solar hot water systems, are available for both homeowners and commercial business owners. Today's renewable energy systems are reliable and have numerous benefits:

  • Clean and reliable energy
  • Job creation
  • Added resale value to the home
  • Cost of electricity offset over the lifetime of the system
  • System longevity—solar panels are generally warranted for 25 years and have an expected life of 40+ years
  • Low operation and maintenance costs

Types of Solar Systems

  • Solar Electric - Photovoltaic Energy
  • Solar Hot Water Systems - Solar Thermal

 

Diagram of solar panels and how they work

 

How it Works:

Use the sun's energy to create electricity. Photovoltaics, or solar electric systems, are a semiconductor technology that convert light energy into electrical energy. Here's how it works:

  1. Photons from the sun strike the face of a solar cell, which is made up of two layers (silicon and either boron or phosphorus).
  2. Photons knock off electrons in the base layer and bounce them to the upper silicon layer.
  3. The electrons travel through a wire from the top layer to an inverter, and then return to the bottom layer of the cell where they begin the journey again.
  4. The inverter converts electricity from direct current (DC) to utility-grade alternating current (AC).

 

Types of Systems:

Off-Grid Independent System:

  • No connection with utility lines, which makes it most practical in isolated locations.
  • A set of batteries store the electricity, although a gasoline generator is sometimes used for emergency backup.
  • This system will frequently make use of more than one resource.

Grid-Connected System:

  • The system is connected to utility lines.
  • It provides the benefits of renewable energy with the consistency of the utility.
  • Utilities allow net metering, which enables surplus power to be sent back to the grid and power to be drawn from the grid when more electricity is needed.
  • When the grid is down, there will be no electricity available.

Grid-Connected Battery-Backed System:

  • This system combines the consistency of being connected to the utility with the ability to store excess power in a set of batteries.

 

 

solar hot water system diagram

How it Works:

Use the sun's energy to heat your water. Solar hot water heating systems consists of solar panels, in the form of collectors, which are connected to the building's existing water heating system. It is one of the most inexpensive renewable energy systems and often has a fast economic payback. 

Components:

  1. The flat-plate collector system (most common type) is composed of an insulated aluminum box with tempered glass on the front. Behind the glass, there is a black plate with a grid of copper pipes attached to it. A non-toxic antifreeze mixture fills the collectors and all piping.
  2. When the sun shines on the collectors, the antifreeze mixture heats up.
  3. A pump circulates the heated antifreeze mixture from the collectors to a heat exchanger.
  4. The heat exchanger transfers the heat from the antifreeze mixture to the water, which can then be used for either domestic purposes or as a space-heating system.
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