An Introduction to Solar


Last week on Thursday and Friday I attended the Solar Power 2005 conference. My primary goals were to try and talk with some of the public companies that I follow in this sector and also to try and gain a better understanding about the industry. I understand the fundamentals of solar technology, but I was looking to get a better understanding of the industry itself and not just the technology. This conference (like many other industry specific conferences) was geared towards people that are already in the industry. So being at an industry conference like this and talking and listening to people that live in this industry is a great way to gauge the health of that industry. Overall, everyone that I met with and overheard was upbeat about their business. Everyone seemed to have more work than they could handle. I overheard that there were several new faces and companies at the event. It was also reported that the attendance of over 1,300 was larger than normal. These are all healthy signs of a growing industry. The first session of the conference was ideally suited for me since the focus was an “Introduction to Solar.” There were about 200 people in attendance for this first session. Here are my notes from this introduction session. You may find some interesting tidbits in here, I certainly did. solarpanel.jpgThe use of solar power has be used for almost 200 years. In the 17th and 18th centuries people used to coat water storage tanks with solar absorbers so they can heat the water for showers. The last time solar energy was in prominence was during the 70’s during the last oil shock. At that time there were many tax incentives to install thermal solar panels used to heat water. The speaker at the conference stated that “These tax credits were one of the worst designed since people were actually able to make money on the credit by installing cheap and poor performing systems.” This gave the entire solar industry a bad name during this time frame and it has taken over 20 years to overcome this tax dodge reputation. Today we have solid companies and new technologies that are not just solar thermal based. With the 2005 Energy Bill that was just passed, we also see the return of solar tax credits and incentives. But these incentives are tempered with limits. Today we have three predominant uses of solar power.

  1. Thermal solar: which is still in use today but new technology have vastly improved the performance.
  2. Photovoltaic Systems (PV): which is where people now equate what solar energy is all about. These PV systems can be either crystalline silicon based, photo sensitive polymer based, or organic based photo receptors.
  3. Concentrating Solar Power (CSP): systems are based on a series of mirrors or reflectors that focus the sunlight into a central photo receptor. These systems tend to be very large and produce hundreds of megawatts of power. The Stirling systems are an example of this technology.

Now when someone typically mentions solar power, most people now think about PV systems and the silicon based technology. PV is easy to understand for most people since they have been exposed to this technology for many years. You may have a solar powered calculator sitting on your desk now and these have been around for over 30 years. sharp_roof_close.jpgBack in the ’70’s the government was researching energy independence and a great deal of research capital went into PV technology at this time. There was also a great deal of research into PV as power requirements for in-orbit space flight required cheap electrical generation. Over the last 25 years the the costs have decreased and the technology has improved. The biggest advance in the reduction of cost were primarily based on advanced manufacturing techniques. Many of the solar cells used to be hand tied onto the platform. Now with automated manufacturing solar panels can be constructed in minutes compared to what used to take 6 hours. There has been a consistent 5-7% decrease in cost per year. However, the raw materials are now becoming an issue. 95% of all PV solar panels utilize silicon to make the photo receptive cells. Silicon is now facing a sever shortage. The silicon usage has grown over 10 times from 1996 to 2004. The biggest contributer to this increase is caused by the semi-conductor industry. The internet dot com bubble of the 90’s had many of the silicon manufactures ramping up to meet the supply. When the dot com bubble burst, the silicon suppliers were left holding their excess inventory and they stopped investing in new manufacturing plants. The solar manufactures were able to use this inventory at dramatic savings as they started to ramp up. That inventory is now dried up and the solar panel manufactures are now using over 1/3 of all the world supply of silicon. New silicon manufacturing facilities are under construction now but are at least 1-2 years out from coming online. So this demand imbalance may actually cause the cost of PV solar panels to increase over the next couple of years. Many of the new and exciting PV technologies don’t use silicon in their construction. They can use synthetic polymers or organic materials that can be printed onto the thin films. This process is very similar to the photo film technology. There is also research in nanotechnology to provide alternative methods to coat photo sensitive surfaces. These new non-silicon based technology is where most of the interest and R&D is currently being focused. solar_stirling.jpgThe third type of solar power is Concentrated Solar Power (CSP). The typical PV systems are considered distributed technologies. The energy generated will be at or very near the point of use. The CSP technology uses the typical utility company model where the power is generated at a centralized facility and is then transported to the location of usage. The typical CSP system will house acres of mirrors that focus the sun power to a photo receptor. There are also systems that utilize troughs that super heat fluids for the generation of power. These systems are typically used for multiple hundred megawatt applications. This technology was heavily developed in the ’80’s but went underground due to lack of funding. With the passage of the recent Energy Bill the interest in this type of technology has seen much greater action. Privately held Stirling Energy has recently signed contracts with SCE and SDG&E to provide electricity from its CSP based fields. Many people feel that you have to live in the Southwest in order to utilize solar energy. The reality is that the entire US is ideally suited for solar. When you look at solar usage, the US is currently third behind Germany and Japan. Both of these countries currently have the solar footprint of Northern Michigan, but they are both able to make solar power work for them. This is the first of many postings about the conference. I will try to have everything posted over the next day or so, so please stay tuned.


  1. This was a great blog, I wasn’t able to attend the Solar Energy Conference and was so happy to find your notes on here. Thank you for sharing the information and I look foward to learning more.


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