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Interview with Dr. David Lee, CEO of BioSolar - Renewable Plastics In Solar

Last week I had the opportunity to interview Dr. David Lee, Chief Executive Officer of BioSolar.  Dr. David Lee founded BioSolar in 2006 in an effort to make renewable materials for the packaging of photovoltaic cell converters.  Dr. Lee holds a Ph.D. in Electrical Engineering from Purdue University, a Master of Science in Electrical Engineering from the University of Michigan - Ann Arbor, and a Bachelor of Science in Electrical Engineering from the University of Texas at Austin.  It was a wonderful interview that provides insight into the company's mission, research and commercialization. 

I am going to start off by asking about your previous work experience.  You have worked for Applied Reasoning Systems Corporation and RF-Link Technology, Inc.  Both of those did not have anything to do with solar industry.  One was an Internet software company and the other a wireless technology corporation.  What made you take the leap into solar technology?

Actually, it is not a long story.  I majored in electrical engineering for my bachelors, masters & Ph.D.  One of my hobby projects was solar technology, especially the material science side of it.  Even though I ended up getting a Ph.D in communications science, my interest level has always been there.  

My first job was at a defense contractor where we designed satellite communication systems for the U.S. government.  I was a systems engineer.  The job of the systems engineer is to oversee the entire project.  That involves many different disciplines, not just communication systems disciplines but also different sub-systems that constitute the entire project.  My background was much more broad than what most people think.

You mentioned my experience in RF Technology.  It was a wireless technology company that dealt with both terrestrial and wireless communication devices.  Applied Reasoning was a software development company.  It also had a lot of space technology related implications in its application. 

I did not simply start the idea of a solar company all of a sudden.  I always had the dream of making solar technology something we can all take advantage of. 

As a follower of the solar industry for a number of years, I know that most solar companies focus on the solar converters themselves and new materials for those solar cell converters.  What made you decide to focus on the packaging of the solar cells instead of the actual converters?

Solar technology has been basically continually improving over the last forty years.  Crystalline and silicon solar cells have been around for a long time.  In fact over ninety percent of the photovoltaic market uses conventional technology of crystalline silicone.  This is what most people see on the top of residential roofs as a glass top.  These are rather heavy panels lined up on the top of peoples' homes.   

There are new technologies that are popping up in the last ten to twenty years.  The general category is thin film technology.  Some use the same silicon based photovoltaic junction cells.  Others use CIGS, copper indium gallium selenide, and CdTe, Cadmium Telluride.  There are various technologies popping up and other technologies that focus on different ways of generating solar energy.

One thing we found in common in all these technologies is that everyone has done such a good job in solar generation techniques and materials.  As a result the efficiency of all solar panels available in different technologies have been going up continually for the last twenty years.  We are finally reaching a point where the efficiency gains are so successful, that we are reaching a tipping point.  There will be so little gain by just increasing the efficiency.  So, they have done a really good job.

One area we felt that no one has ever looked at or tried to improve or reduce cost was the packaging area.  Our Chief Technology Officer, Dr. Stanley Levy, during his tenure at Dupont he was very well known for his solar film, packaging development.  I believed he filed thirteen plus patents for film.  This is generally one of the most important components in photovoltaic packaging.  

As a small company, we knew we couldn't go after all the different packaging available.  We understood clearly that the market could accept quickly was a backsheet component.  A backsheet is a film that encompasses the back of the solar panel.  Its function is to protect the solar panel and provide the appropriate insulation, as well as provide a moisture barrier.  

The backsheet has been around for forty to fifty years and no significant improvement was made.  It worked and engineers simply accepted that it worked. "It works so why change it."

So, the problem is that as the cost of solar modules is pushing down.  As you noticed, most photovoltaic prices have been coming down drastically in past years.  Especially in 2008, 2009.  Because manufacturers are forced to reduce cost to make the cost of dollar per watt to closer to what is being generated by fossil fuels.  We are still quite a bit away but most industry experts expect by 2013 to 2015 we will reach the cost parity.  Meaning that the cost of generating electricity by solar panels may be approaching the cost of generating through fossil fuel technology.  

One of the problems with the backsheet is that they are made from special trillium based plastic materials.  The material is called Tedlar and Dupont is the only maker of it.  Dupont has a patent on it.  It is a beautiful material that meets all the requirements.  It is tough, it is thermally stable and it gets the job done.  There are two problems.  The process of making Tedlar is highly sophisticated and requires the use of toxic materials.  I am sure they are doing a good job of keeping those toxin materials intact so they don't contaminate the environment.  The process of dealing with the toxins is a very expensive process, because of this the price has not been coming down and staying steady for some time.  

So what BioSolar is proposing is why don't we propose something that will replace the typical trillium backsheet.  Something that can be made from sustainable and renewable materials, not petroleum based materials.  So the process of making this new backsheet should be cheaper and involving less toxic processes.  

In the last three years we have been working on many different combinations of materials and processes.  We are finally getting down to the point where we have defined several of our products and the first one is going to hit production very shortly.

And that would be the backsheet?

Yes, we will coordinate Bio-Backsheet C.  It is the first backsheet made of green material that will compete with backsheet material currently on the market.  We believe we can market it at a lower price then what manufacturers are paying for petroleum counterparts.  

David Lee- BioSolar

Going into the research behind this innovation in Bio-plastics, is most of this research done in house at BioSolar or do you rely on research done by Stanford, UC Berkeley, UCLA or Lawrence Livermore Labs?  In essence where is the research coming from?

It is crucial to our product development that it be done in house with the help of third party contractors.  The contractors would have responsibility of doing one experiment or another or manufacturing at the experimental level.  All the technology itself is developed in house.  

Plastics technology is such a complex and capital intensive research subject.  A small company as BioSolar can not do things in the same level as companies being in the business for hundreds of years.  We do have a rich knowledge in one specific area, photovoltaic related materials including chemistry, physics and mechanical research.  

Stan Levy, of course, is a leader in that particular industry in packaging materials.  We do have advisors and consultants who are leaders in their fields.  You can find many of their names at our website such as Prof. Charles E. Carraher, Jr., scientific advisor. 

I understand the proprietary nature of your process, but can you give a generalized description of the process and how you made bio-plastics more applicable to the photovoltaic manufacturing process?

Sure, we are not creating a brand new type of plastic.  I think the name plastic is misleading at times.  There are bio-based materials for many different applications for a long time.  But no one has looked at using these materials for solar applications.  

For example, Nylon 11 resin is dried from Castor beans and that material has been used for underwater cables for a long time.  Which certainly dictates how durable and water repellent the material capability is.  No one every looked at using the material for solar applications.  

Of course, the material cannot be used for solar unless certain processes or certain combination of processes have been applied to it.  But that is where BioSolar comes in.  We are able to identify the materials available in nature and something that has been used, or tested and proven.  We combine these with other materials such as cellulosic films. The cellulosics we are using is from recycled cotton.

So, the individual components to make our backsheet is known to meet certain requirements already.  When you combine that it not only retains the property but possesses other properties that a photovoltaic backsheet requires.  

Again, we are not creating a brand new material as Dupont and others do, but we are identifying available materials to mankind and we combine and process it so it meets the requirements of photovoltaic materials.

Taking a look at BioSolar's business plan there are two phases of development: a first generation and a second generation.  We have talked a little about the first generation which is the film element.  You are trying to modulate that and eventually create a cell superstrate and a cell substrate.

That is correct.

But there is also a second generation, where BioSolar is seeking bio-polymer resins to actually come into the solar manufacturing process.


I was wondering if you could give us information on how far along you are with the cell superstrate & substrate and the second generation bio-polymers?  When can we look for these materials to be available?

Sure, our first goal is to get the Bio-backsheet C, which is the first level product, to completion.  It is getting very close to completion for commercialization.  Of course there will be variations of the Bio-backsheet C that will come out.  We would like to attain commercial success with the first product.

But at all times we are working on the next generation products such as superstrate and mixture resins to create other photovoltaic components.  It is an ongoing process and we have made some breakthroughs, but we are not quite there to commercialize those findings into a product just yet.  

I think it will be several years before it becomes a commercially successful product. Mainly for two reasons. Number one, these are not easy subjects that can declare this is to be used.  As we have seen the last two to three years of company development,  a material and theoretical success, proof does not equate into a final product.  Unless it is followed by a long period of testing and then acceptance.

So, BioSolar plans on focusing on backsheets for the coming year.  We want to make sure this becomes commercialized and financially viable.  Second and third generation products will be in continuous development  As concrete findings are verified, then we will announce them as they come along.  It will not be the short term, it will be at least two years.  Perhaps even three years.

I want to end this interview by talking about major obstacles.  You have already talked about BioSolar being a smaller company than Dupont and that bio-plastics in the photovoltaic process is not an easy subject to do; what do you see as the major obstacles standing in the way of large scale application of bio-materials for photovoltaic manufacturing processes?

So far as the backsheet is concerned, we have not encountered any problem in terms of market acceptance.  Stepping back, when people think of bio-based materials they think of bio-degradable materials.  In photovoltaic applications things have to last twenty five to thirty years in nature. Sometimes in the hot sun, cold weather, in changing environments so there may be a general reluctance of the photovoltaic manufacturers not to take a chance on bio-based materials.  

Bio-based does not mean necessarily biodegradable.  So there may be some psychological barriers but most of the photovoltaic companies are so pressed by the need the compete with other photovoltaic manufacturers in price, they should look at all different areas to reduce cost.  What we are looking at is that we present a 100% green based backsheet and at the same time the manufacturer can save money.  

We are hoping that other than the psychological barrier there will be no other barrier so long as we are able to meet the requirements for photovoltaic manufacturing process and provide a green product at a reduced cost.

Thank you so much for talking with us today, Dr. Lee.

You're very welcome. 


Great interview

I was very impressed with your interview. I have been looking for a good interview with Dr. Lee for a long time. I hope your story get a lot more attention. Good Job!

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