Look around you. Do you have a digital watch on your wrist, a smart car key in your pocket, a cell phone in your hand or a laptop in your briefcase?

We are carrying more and more silicon on us wherever we go.

I didn't notice the creep into my life so dramatically until recently. And now it's impossible to ignore how dominant silicon has become.

I’ve been working in solar (primarily crystalline silicon) for the past two decades, at many factories and at many installations. Before that, I was engineering in a silicon fab for Texas Instruments pulling single-crystal silicon boules and cutting them up into monocrystalline wafers. These days, wafers are further cut into computer chips, or they are made into photovoltaic (PV) cells by infusing boron- and phosphorus-producing solar electric wafers, or PV cells.

By 2013, polycrystalline silicon production, used mostly in producing solar cells, is projected to reach 200,000 metric tons per year. The monocrystalline semiconductor silicon production, used in computer microchips, remains below 50,000 tons/year.

It was a recent trip to an electric utility where I was performing smart grid certifications that made me realize the ubiquity of silicon in our lives.

Today, utilities and independent system operators have computer banks and control rooms that monitor the grid for their territories. These are becoming more sophisticated and are starting to resemble major server farms. In addition, smart meters and sensors along the grid are sending information to both autonomous and monitored controls.

And as silicon-based PV becomes more dominant as a distributed resource, the inverter is handling more of the grid and high-value smart grid functionalities -- feeding that information back into the sophisticated computer banks of utilities.

This animation depicts the inside of a silicon photovoltaic cell and demonstrates how a photon excites an electron.

Silicon is on me and around me at all times, sometimes in very large quantities. Computers are controlling more and more solar cells made out of crystallized silicon every day. And when my data goes into the cloud, a silicon-based infrastructure takes over to manage it.

Sustainability expert Randy Udall got me thinking about silicon’s desire when he asked the question: "What does carbon want from me?"

Those words gave a consciousness to the element of carbon and its place everywhere in our society. Carbon is being freed from a ground-based existence to power our society and become an integral part of our lives.

Carbon is silicon’s analogue, a non-metal directly above silicon in the periodic table.

Which brings us to another set of questions: What does crystallized silicon want from me? Are we controlling silicon or is silicon controlling us?

Silicon is such a special material: an inexpensive semiconductor that can send trillions of zeros or ones around in my computer, or help a solar cell flip an electron into conduction band, freeing it to do work with the help of a photon jolt.

If I recall correctly from chemistry class, silicon is the most abundant material in the earth’s crust after oxygen. It's also the eighth most available element by weight in this universe. It has gained all the notoriety in the periodic table of computing elements that has allowed it to be the star of the earth’s elemental show.

Why does silicon want to be crystallized and be put into service in our society? What can it possibly gain? The only answer I can think of is order. By being placed into a crystal lattice structure by humans, it is more ordered than in its diverse, non-crystallized state. In the near future, crystallized silicon might want to be dominant in energy storage. It probably wants to be recycled and continue to be in an ordered state as long as possible.

One place where you can see silicon presenting itself in these energy/solar/computer activities is at the SEMICON West-Intersolar conference this July in San Francisco. I'm predicting that you will see more and more smart grid gear at this year’s Intersolar SF exhibit. The California Public Utility Commission (CPUC) is now requiring smart grid functionality in PV inverters (new CPUC rule 21). In the north and south halls, the silicon industry's latest innovations will be on display; a few solar companies are often hidden away in the south hall. The west hall is all solar, and the Intercontinental houses the solar sessions. This year, SEMI is also hosting some PV sessions.

It is exciting to see the PV industry rallying around the transformative power of silicon. Keep watch as this element continues to shape our future -- and our energy system.


Joseph McCabe is a solar industry veteran, an American Solar Energy Society Fellow, and a professional engineer, and is internationally recognized as an expert in solar including new business models for PV. Joe can be reached at energyideas {at} gmail {dot} com. 

Acknowledgements: Michael Pollan’s The Botany of Desire inspired this piece. Thanks are also due to Randy Udall.