We get a lot of questions about how the exact location for the “PG&E Solar Schools program Solar on a Stick” gets selected. The story about how the spot was picked at the Presidio Middle School in San Francisco (right on the north side of Geary) illustrates how this process is a little bit science and a little bit math with some important diplomatic negotiations thrown in.

Science: The solar panels are installed at the top of a pole and angled toward the sun. They have to face south and there should be nothing shading the panels. All of the PG&E Solar Schools projects are installed as close to the same conditions as possible to make sure that schools are able to compare/contrast solar systems with location and weather as the dynamic variables affecting performance. What is under the panels and around the base of the pole doesn’t really matter much, but we never want anything between the panels and the sun. There are normally a lot of areas available at schools that work well for the installation, but urban schools can present a bit more of a challenge. We don’t want to impact playground space and need to work around existing structures. We use a device called a Solmetric SunEye that measures the path of the sun and basically tells us whether or not each location is good, bad, or in between. I have to tell you that Alyssa usually does this so I am going to let her explain the devices that she uses to “test the sun.”

Thanks Glen. In the past, we used a device called a Solar Pathfinder, which has been around since the 70’s and still works well. Many get a chuckle out of the fact that I refer to the 70’s pathfinder device as “old school” but still good! In fact, we often start with this device as the lower tech (but still accurate) tool.

We walk around the school campus, and discuss which areas:

1. Are preferred by the administration (this is where the diplomatic negotiations start - everybody has a different opinion, and we need consensus before we can move forward),
2. Are relatively unobstructed by trees or structure shade and “safe” from flying objects (other than the sun’s rays),
3. Are relatively close to where we need to connect the system to a panel to feed the clean solar power into the classrooms.

We triangulate between these three necessary inputs, and take measurements at each site. When we get close to one or two potential locations, we take measurements with a Solmetric SunEye - this is the high-tech updated tool. Below is a sample of an image taken from Presidio Middle School. The lines represent hours of the day and months of the year - this site, as you can see, is pretty darn close to perfect! But the story doesn’t end here.

Math: We have to make sure that the installation is not too far from the electrical box where we connect the solar array with the PG&E electricity grid, and that the numbers work (see the Solmetric chart above). It is expensive and disruptive to run wires underneath asphalt and concrete, and even to trench in a grass yard. There can be some loss of electricity when the wire carrying the solar energy has to travel a long distance. Some of the “solar on sticks” had to be put pretty far from buildings just because of shading and other issues, but we try and measure the distance between the site where the pole might go, where the PG&E service comes in, and where our closest electrical subpanel is located. We also can’t be within 10 feet of a retaining wall or structure because of code restrictions. We weight all of the necessary inputs, and then talk as a group about the preferred location. As you can guess, not all of the inputs can be quantified - future plans for the site, personal opinions on aesthetics (including those of neighbors), and other topics come in to the discussion.

Compromise: Finally, we have to take the school’s staff and students and activities into consideration. We won’t put the panels in front of a walkway so the students would have to walk around it, and we don’t want to put the pole in the middle of a baseball field or soccer field or basketball court. We need to keep the fire lanes clear. Our favorite spots are unobstructed spots in the front of a school or near the science classrooms so that the students can see the solar panels everytime they walk in or from their desks in the science wing where they might be looking at the online data monitoring site. Ultimately, there are often non scientific and non mathematical compromises that determine the final location. And this is where we get back to Presidio Middle School, and finish our story about X marking a spot.

The Presidio Middle School is a huge and beautiful historic looking building built in 1930 that sits off of Geary Street in San Francisco. There is a wonderful gymnasium and expansive playground. The walls and roof remind you how we used to build schools a very long time ago- we built them to stand for a long time, and the artistry of the day was included in the building lines. I love the look of that school.

When we first visited the school we met with school administrators and we selected a spot for the pole based on a number of the factors that I talked about above. The location was good and everyone present agreed to it. But then Alyssa got an update from Assistant Principal John Greener. He said the woman in charge of physical education opposed the spot for the solar on a stick installation. She had plans for a long jump track in that area and the pole would interfere with her plans. She had not been at the original meeting, but she was now voicing her opposition to the area of the playground where we were about to do the installation.

So Alyssa and I met John Greener at the school office and he called several of the science teachers and the PE teacher to the playground. Alyssa and I walked around and Alyssa used her device to make a mental note of the locations where the pole could go and then we all met in a group discussion in the middle of the playground. We talked about the science issues and the math issues and then we got around to the location we had chosen originally. The first location seemed impossible, but an interesting thing happened. The PE teacher started asking about all of the various locations where the pole could go and a funny thing happened. She made a suggestion for a location and we all looked at it and everyone nodded, “that works.” It was in fact a better location from a science perspective.

For me, the spot did not look like it would be acceptable to the woman in charge of the playgrounds because it was in the middle of the playground. But what none of us had realized was that the location she offered to us was in between a number of play areas. While it is centrally located, it does not interfere with any individual play area. We had all tried to find a location that was a little “out of the way” of the play areas and she had come back with a much better location for us that is in the middle of the entire playground and very visible to traffic on Geary. We could not have picked a better location. (I did ask everyone from John Greener to science teachers to the PE teacher to Alyssa to point to the spot so that we had evidence that this was in fact the location, but I did it more for fun than to resolve any future disputes. The fight was over and the compromise worked out so much better for the project than any of our original choices. The day Alyssa and I drove to the school it sounded like a fight was brewing, but in the end everyone was laughing and happy. Science and math had won a victory…on the playground.

Story submitted by Glen Kizer

Recently I have spent a lot of time at Oakland High School because our solar school team has been working to install a system as a part of the PG&E Solar Schools Program. The system is in and there will be a solar celebration this spring, but I have been privileged to go into the school and to get to talk to some of their students and staff. What I have found is that Oakland High School (OHS) has its own solar school team and it is working well.

I spoke to a number of their AP Science Classes and two (2) block classes of 10th grade biology and I also spoke at their Science Teachers Meeting after school. Katie Noonan and Kevin Jordan, who are co-Directors of the Environmental Science Academy at OHS, asked me to talk to their students and fellow science teachers. The Environmental Science Academy is open to all OHS students and has been in existence for 10 years.  They receive special funding from the State of California and they take field trips with an environmental slant to them.  Ms. Noonan is trying to organize a tour of a nuclear power plant. 

Everyone is so excited about the fact that their school was accepted in the PG&E Solar Schools Program. Katie and Kevin have their classrooms directly across from one another and for some of the class periods they would combine students in one room or another. Both Katie and Kevin were nice to ask me to come in, and while it appeared that I was running the classes, the two of them kept things on track and were in complete control of the direction of the discussions. I realized how some really good teachers make teaching look easy, but after staying in those classrooms for hours, I also realized how really hard it is to teach. If I were the President, teachers would make more money. The students asked questions all day and the Oakland HS science teachers all seem extremely intelligent and completely committed to their students and to the sciences. Some of the teachers have been to the NEED training and more are going. It is obvious from their excitement that solar energy will become a big part of their science curricula.

In fact, a teacher, Ceasar Lopez, has a solar car contest in his 9th grade science classes every year and his class won a nation wide competition using a solar powered train.  And Ms Noonan once had a student design a solar powered water treatment plant.  This school was already excited about solar energy and now they have their own “solar on a stick” that makes electricity for the school every day. 

On several occasions I have also been able to meet with Principal Mary Scott who may be the perfect principal. She is tall and confident and appears to be both strong and yet very nice. Principal Scott is also excited about the PG&E partnership at her school. She also talks about how nice the “solar guys” were and how they moved some lunch tables for her and how well they cleaned up the spot after the installation was complete.

Ms. Scott arranged for the pole to go in next to one of the primary doors so a huge percentage of her students see the solar panels several times a day. It is also positioned just outside the science department. She is committed to the solar project and everyone understands this at the school. The administration is completely supportive of this project and that is always important because the students and the faculty need to know the business side of the school has their back. At OHS, the administration is behind them.

If the students, teachers, and school administration are three (3) of the teammates in this project, then the final player on the OHS Solar Team may be security. There is always a threat of vandalism at any school and the solar array does sometimes attract vandals. In the hundreds of installations that I have been involved with there have been almost no acts of violence against any of the solar projects, but there have been a few and it has to be considered every time we do an installation.

At OHS, the security guard near the solar panels is named Tesfai Haile, (I took a picture of him after the pole went in and then another after the panels were installed…a kind of before and after.) The first time I parked near the spot where the pole was to be installed, I worried my car would be towed, but Tesfai told me not to worry and I didn’t. After that, whenever I visit the school, I go to the back and look for Tesfai and he talks about how much better the weather is in California than Ohio (where I am from) and then we talk about solar and the students and security. Like Principal Mary Scott, he is nice and is always smiling, but he also appears to be strong and smart and is constantly watching over the school yard looking for trouble. But he is not only protecting the school, he is also watching out over those solar panels. I am sure PG&E feels better about the fact that Tesfai is watching out over their gift.

So, Oakland High School has a working solar electricity system that will help their students understand how 100% clean electricity can be generated right there on school property. Teachers will use the PV system to help teach science and math and the administration can help introduce renewable energy to the neighborhood. And all of them now understand how working together as a team they can accomplish something that none of them could have done on their own. This is a great project at a great school with absolutely wonderful people and I believe more great things are coming for their “solar team.”

With school budgets shrinking as fast as our polar ice caps, it is not always easy to come up with hands-on solar projects. Thanks to NEED, the National Energy Education Development project, we used their plans to build the fastest, lowest cost, most portable solar oven not on the market. Let me introduce Sydney, a bright, social, and witty 8th grader going to school in Paradise California. Here she recounts a solar project she did two years ago:

Hello my name Sydney Zimmerman I am 13 and an 8th grader at Paradise Intermediate. I am also a teacher’s assistant for Evergreen 6 - an amazing solar school. I was enrolled at Evergreen 6 in the 6th grade where I experienced solar energy for the first time. Mr. Holman fascinated all of us with solar energy. Well I am not a fan of science but solar energy was a subject that I was amazed with and still am. Just like the rest of Evergreen, we were anticipating the arrival of our new solar system. There was so much to learn about. We were having different lessons about solar energy everyday. With little examples everywhere there was so much to take in all at once. Evergreen taught all of us how we can cook using solar energy. One way they taught us how to cook with solar energy was using Solar Hot Dog Cookers made from Pringles cans. It was so much fun and really easy to make these cookers.

From the NEED Project Instructions (Download here- need-solar-hot-dog-cooker.pdf):

• Cut Pringles Can. Cut a 7′ line going horizontal on the side of the can then on each end of that line cut a 3′ line going vertical. Bend the flaps back but do not remove the flaps from can for they are important in cooking your hot dogs.
• Cover opening on side of the can with a transparency film and tape film into place.
• Make two small holes - one on the metal end of the can and another on the lid. Remove lid from can.
• Put hot dog on skewer. Fit the skewer through the hole on the bottom of the can. Then put on the lid fitting the other end of the skewer through the hole on the lid. The hot dog should now be in your cooker.
• Place the Solar Hot Dog Cooker into direct sunlight. Making sure the flaps are reflecting energy onto the hot dog.
• Time how long it takes to cook your hot dog.
• When Hot dog in cooked remove out of Can and enjoy your delicious Solar Cooked meal!

* You Can Experiment with your cookers using other high light sources.

Two useful tips we have learned at Evergreen over the years:

1. To make the hole in the metal end of the can, gather up a nail and hammer. Place the plastic lid over the metal end of the can. Use the small plastic dot in the center of the plastic lid to use as a pattern. This will allow you to hammer the nail dead-center in the lid and metal end at the same time.
2. Roll the 8.5 X 11 transparency film into a loose roll. Slide it into the can fom the open end. When you let go, it will expand to the size of the can’s interior, not needing tape to hold it inside.

It was a lot of fun to make these cookers and it did not cost a whole bunch. The kids get to experience solar power using something that they created themselves. I think that all teachers should try this project the kids bring in their own Pringles can and all you provide is a skewer and a transparency film, it is that easy! The kids will have fun and be able to eat what they make. It taught us a whole bunch on how solar energy can be used in different things and can be used in our normal daily lives.

These ovens are great for hikes, lunch, and to take home when they are done. Many students report taking them camping and sharing the ovens with family and friends. For those that “do not eat hot dogs,” remember there are turkey dogs and garden dogs out there. “No-Smoke Smores,” Bagel Bites and mini cheese melts can also be made in these ovens. On a hot day, hot dogs can be cooked in around 15-30 minutes. If your hot dog gets finished early, just aim the window away from the sun to keep it warm. For interesting flavor, some report a mild taste of the variety of Pringles that originally came in the can - just be careful not to clean it out before use.

Whatever your budget, Pringles can solar cookers are a great introduction to solar energy. Often students will start to think of other ways they can harness the sun’s free energy…

Spring and summer may seem to be a long way off, start collecting empty cans (with lids) now - you may be ready in time for solar hot dog season!