Home Solar Energy, Types of Solar Cells, and Silicon Sourcing (Part 7)

In this article, we will document the three most common types of solar cells and how this technology has proven itself for decades. We'll also give a brief history of silicon sourcing and explain why we were set for rapid growth back int the 90s and now we are again. Finally, we'll make note of new solar technologies that will change the solar industry as we know it (i.e. thin film and nano-solar). All of these factors are great news for homeowners wishing to upgrade to solar generated electricity.

The following topics will be explained in varying levels of detail; how a solar cell converts sunlight energy via the use of different types of silicon, the use of silicon and where it comes from, and a little about the history of silicon sourcing over the past 18 years.

The Future Solar Panel and Home Solar Manufacturing

As the residential solar power industry has matured and showed a steady growth of about 40 percent a year, the silicon industry is now responding with new production and caches of raw materials. Many silicon refineries and new silicon sourcing companies are getting the funding and moving towards rapid production in the next dozen or so months. There are plans and announcements by several companies such as GE, BP, and others about launching new facilities that produce silicon at a fraction of the cost we may be experiencing today. This is all exciting news for home solar power enthusiasts and for those wishing to upgrade to residential solar generated electricity.

The silicon industry is or has been slow to increase overall manufacturing capabilities because of the large growth during the early 1990s that eventually when stale. The extreme growth expectations were hyped and many industry experts expected much expansion in the early 1990s. This just did not happen 18 years ago. Fortunately, we are now experience much more accepting market, social expectations of our movement to renewable technologies, and governmental support to make the switch to home solar power.

In the past, the solar silicon refining industry made solar panel manufacturers sign long-term contracts at extremely high prices to secure any silicon at all. For example, a solar manufacturing plant had to slow production to a trickle because of a lack of silicon. The economics have now changed since 2006 making massive silicon contracts viable at better prices.

Nano-Solar and Thin Film Solar Cells: It's the Future

We are now at the dawn of a home solar energy revolution. The solar power manufacturers invented and are beginning to manufacture new solar modules that do not use silicon at all. There are alternative materials using nano-technology that are and will continue to radically change the consumption and production of solar generated electricity.

Often the newest technologies, like thin film or nano-solar cells, are somewhat experimental with limited or no actual field testing. This is not true for many of the silicon based solar panels on the market today. Homeowners, right now, have the opportunity to rent residential solar energy systems and side step the expensive system purchase by renting. Because there are now large sources of silicon, homeowners now have the choice to upgrade to solar on a large scale across many markets in the United States that were once thought too expensive to install residential solar systems.

Sourcing of Silicon for Home Solar Energy Systems

The material used to make most solar cells today is the abundant element called silicon. In simple terms, silicon is one of the most common elements on Earth. It really is no more than sand. It can be melted down, added to other materials, and manufactured into thousands of products. Availability of solar grade silicon has been one of the limiting factors in the solar module manufacturing industry for the past several years.

The story goes something like this. Solar grade silicon is produced in large scale, expensive to build processing facilities. "Well, isn't it just sand?" One might ask. Of course, sand is basically silicon, but with a lot of impurities. Solar grade silicon is highly refined silicon that is purified through gasification and then "doped" with precise impurities to create free electrons, which is explained in following articles.

There are basically 3 types of silicon going into current solar energy systems being installed today;

1. Silicon Crystals: A silicon atom has a positively charged nucleus that is surrounded by negatively charged electrons. The critical thing about silicon is its structure. It has 4 electrons around its nucleus that allow for easy bonding to other elements and for its organization into crystal. Crystals conduct electricity much better than randomly organized elements. These outer electrons are available for bonding to other electrons. Every silicon atom bonds with 4 other silicon atoms to make a repeating crystalline structure.

2. Monocrystalline Silicon: The silicon is grown as large cylinders, which are sliced into wafers that become individual solar cells.

3. Polycrystalline Silicon: Liquid silicon is poured into thin containers and cooled.

Emerging Availability of Home Solar Energy System

Want to know how to rent a home solar electric system for your house? Well, it's pretty simple. You basically pay a flat monthly rental fee just like you do today for a satellite dish or some other equipment you rent. The solar system rental rate is calculated based upon a number of factors; the average monthly energy consumption, the available utility sources and net-metering options, and the kWh rates in your market. A solar engineer will come to your home, look at your roof size, angle and shading to size the system for your location.

Going solar and using renewable, solar energy is getting simpler every day. The following article explained in some detail why the sourcing of silicon has slowed in the overall residential solar power market in the past. This is just not the case any longer and more options are emerging daily for the average homeowner to rethink solar power and renewable solar energies.