Posts tagged ‘photovoltaics’

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2011 May 22 19:18
by roma

NABCEP Preparation, Toastmasters Ice-Breaker


All this week, I have been going through Heatspring Institute's Solar PV Installer Boot Camp Training. Most of the preparation material is from the Photovoltaic Systems textbook by James P. Dunlop. The book is over 400 pages, so one of the values of the course is that it focuses on the important concepts, only. If it wasn't for that, it would be quite hard for me to identify the crucial topics, as I usually tend to rely on the side of over-learning.

I've also been working on my Ice-Breaker speech for Toastmasters. I will present this speech on May 25th. There are so many things to choose from in my life that the hardest part is deciding on what not to include. I am reminded of Garr Reynolds' focus on the importance of simplicity in Presentation Zen.

2011 May 1 20:07

NW Solar Expo (Saturday and Sunday)


Helped Solar Oregon with a model electric car demo exhibit at the NW Solar Expo over the weekend.

The organization had gear-driven and pulley-driven solar car kits from SunWind.ca on hand. We (volunteers) assembled the cars on Saturday. We then took them apart half-way, leaving the axle and motor mounts on the body. Expo attendees re-assembled the cars and raced them down a track.

Since we were inside, we needed a light source powerful enough for the solar panels. Ironically, this turned out to be 20 incadescent light bulbs connected mounted on a PVC-pipe frame. Here we were on the warmest day of the year (so far) showing the wonders of solar energy by powering PV panels with light from inefficient bulbs.

I realized that this situation mirrored the overall state of the renewable energy industry. Renewable energy is good. To show this to the non-converted public, however, companies must concoct elaborate schemes through which the public wonders "why bother?". This is not necessarily the fault of the energy industry. Just something to consider. If we want to convince not just the converted, we must leave not one inkling of doubt and we must make the show grand.

We had no ruler when we were assembling the kits on Saturday morning, so many of the axles were a bit misalinged. The value in this exhibit was thus not only the ability to see solar cells in action, but also to experience tinkering with the design of the solar cars. Some attendees didn't have patience and had us help, but many chose to persevere and figure out how their designs could be improved.

Video of a race:


The curiosity of a boy named Cadence, who came in with his mom, just couldn't be satiated. He stuck around for almost 2 hours. After assembling the regular car, he started experimenting. This video shows his super car with two motors:


Don, who thought up of this whole idea, kept saying that the sun powered these cars much better than our bulbs. I took the car outside to test it:


As we were packing up, I spoke to Don about the deterrents to a more widespread acceptance of solar. Don mentioned that save for Arizona, nobody thinks that their locale has enough sunlight to justify using solar panels. Very interesting and valid point! Food for thought!

2011 April 29 22:10
by roma

NW Solar Expo - Friday


I volunteered at Expo's information desk after returning from SolarWorld. Quite a bit of networking. I got to see some people I had met before. Chance Currington from SunLightSolar gave me some excellent advice about networking and strategies for learning more about the industry. I also saw Matt Lind from Advanced Energy Systems, whom I met two weeks before at the FutureEnergy Conference. I met some other folks with whom I had interesting discussions.

The exhibitors were mainly solar module, inverter and rack manufacturers, local and regional contractors, roofing companies, and data companies. I'm struck by the absence of Asian PV manufacturers. No Chinese and Japanese companies? Interesting.

I'm volunteering at the Expo again tomorrow and Sunday.

2011 April 29 21:59
by roma

Largest PV Plant in the Western Hemisphere


SolarWorld, which operates a PV manufacturing plant in Hillsboro, arranged a tour for attendees of the NW Solar Expo. I got to go as a volunteer.

We assembled in the morning at the convention center for a 1-hour intro class by Danny Hytowitz of SolarWorld. We then went to the plant by bus. At the plant, Kevin provided us the tour.

Kevin wanted to show us as much as possible, so he conducted the tour at a brisk pace. There were about 10 attendees in total. Most were small-scale contractors and some government agency representatives.

Kevin showed us some panels from SolarWorld's earliest days. I got a chance to take a photo of the raw silicon that SolarWorld sources (unfortunately we weren't allowed to take pictures during the plant part of the tour). Turns out, a lot of it is from Russia.

The first thing that we saw through a window out onto the plant floor as we were roaming the hall were a bunch of cardboard boxes with labels C through D. Kevin explained that these silicon wafers, which did not meet SolarWorld's QC, would be sold to competitors. ! Throughout the tour, Kevin kept stressing that SolarWorld tests ALL its products, throughout the different stages of the manufacturing process.

We then went up to the second floor and saw, once again through a window, a room where about 80 20-foot tall machines were growing silicon crystal. Here and there were technicians checking up on things, but this operation was without a question the work of machines. 21st century!

I found out from Peter Hicks, SolarWorld's new western region trainer, and a former employee of SunEdison, that the silicon in these ingots was doped with boron before the melting process.

We then made our way to the factory floor where the round ingots are "squared". This shape is what you eventually see as one of the 60 cell in a solar module.

We stood in the hallway listening to Kevin speak while a very industrious robot arm 10 feet away was busy putting labels on different components.

We walked in the hallway adjacent to the part of the plant where wafers were made into cells. It was here that the tops were doped with phosphorus (I learned this stuff just in time to understand the science behind this perfectly). We passed a room with what looked like small nuclear reactors. This was SolarWorld's water treatment facility (they reuse water 4 times before sending it out to the city's water treatment facility).

Kevin then took us to the adjacent building, where the ready cells are soldered into strings of 10. Six of these strings are then laminated onto glass, which is then attached to a frame. We were on the second floor overlooking the plant floor, near the engineering division. A guy at a desk was speaking German on the phone (SolarWorld started in the US, but was bought by a German company. Its headquarters are now in Germany). We didn't get to see this part of the manufacturing process because of a maintenance break.

Overall, I was very impressed with the tour and the company. A lot of companies talk about sustainability. SolarWorld seems to be act on its desire to minimize the environmental impact at all stages of its operations and its product's life cycle. I like to think it's their German roots. Without a doubt, seeing this factory in action was a special treat and quite inspiring.

I went to speak with a representative from Kelly Services, a recruiting agency that oversees entry-level factory floor jobs. However, the representative told me to just apply online.

2011 April 28 13:30
by roma

Understanding How PV Cells Work


I opened up a pamphlet from SolarWorld explaining how photovoltaic cells work, but wasn't satisfied with the explanation geared towards the layperson. N-type, P-type? What is this stuff?

Turned out that I had to go all the way back to my 1-st year college chemistry textbook. It took me a couple of days to review electron orbitals, valence electrons, periodic table properties, electronegativity, and metallic, ionic and covalent bonds. All done with the help of videos at khanacademy.org.

Finally, I got to the bottom of the actual constitution of a photovoltaic cell. That is, I can picture the extra electrons floating around in the matrix of the silicon - phosphorus mix in an n-type layer. I can also visualize the "hole" created by a lack of electrons in the silicon - boron mix of the p-type layer.

I posted some lingering questions on the allaboutcircuits.com forum. In the meantime, I will go onto reading about different types of fuel cells, as well as reading about photochemistry.