The real genes of Geniverse

Did you know that while dragons and their model species drakes are fictional and fanciful, the genetics of these virtual Geniverse creatures is based firmly on the real-world genetics of model organisms?

The drake genes and traits have been carefully compiled from the actual genes and associated traits of the anole lizard, mouse, fruit fly, zebrafish, and other model species. The genes for forelimbs, wings, color, and other drake traits are genes that are involved in the development of those traits in real organisms. There’s real biology behind the Geniverse narrative as well: the disease that plagues our hero’s dragon friend is modeled on a rare human metabolic disorder, ornithine transcarbamylase (OTC) deficiency. In fact, since the genes of humans are similar to the genes of the model organisms we use in real life—that’s why we can learn so much about human genetics from them—the genes of the Geniverse drakes are quite similar to human genes.

In addition, the interactive models that students use to conduct virtual experiments in Geniverse are powered by genetics programming that accurately simulates real-life patterns of inheritance in humans as well as model organisms. Students who learn with Geniverse are learning to analyze experimental results that would be obtained from these genes in a laboratory.

Nomenclature Genomic Location
Symbol w Chromosome 1
Name wingless Linkage map 70 cM
Species Dracomimus familiaris Genome coordinates unknown


Summary information
Phenotype: The wingless gene affects wing development in drakes. Homozygotes for the wingless allele (w/w) lack externally visible wings entirely. The skeleton of wingless drakes has a vestigial dorsal shoulder and a remnant of the proximal wing bone. Note: This gene and phenotype are taken from the fruit fly, d. Melanogaster, and the human correlate gene, called Wnt1, is 80% similar to the wingless DNA sequence.
W/W or W/w w/w


Alleles and Phenotypes
Allele Summary
W Presumptive wild-type allele
w Recessive allele
Genotype Phenotype
W/W Normal wings
W/w Normal wings
w/w wingless


Nomenclature Genomic Location
Symbol Wnt1 Chromosome 1
Name Proto-oncogene Wnt-1 Linkage map unknown
Species Dracomimus familiaris Genome Coordinates 1: 70 Mbp

At the University of Massachusetts at Amherst, students are utilizing bioinformatics tools to build new drake genes, mutant alleles, and phenotypes based on investigations of the scientific literature. In an exploration of multiple genetic mechanisms, students have created drakes whose genotypes give rise to deafness and dwarfism, cancer and cold tolerance, polydactyly, and the ability to spit spider silk. We’re thrilled to see these additions to our drake genome!

Modeling linear Fresnel reflectors in Energy3D

Fig. 1: Fresnel reflectors in Energy3D.
Fig. 2: An array of linear Fresnel reflectors
Linear Fresnel reflectors use long assemblies of flat mirrors to focus sunlight onto fixed absorber pipes located above them, thus capable of concentrating sunlight to as high as 30 times of its original intensity (Figures 1 and 2). This concentrated light energy is then converted into thermal energy to heat a fluid in the pipe to a very high temperature. The hot fluid gives off the heat through a heat exchanger to power a steam generator, like in other concentrated solar power plants such as parabolic troughs and power towers.

Fig. 3: Heap map view of reflector gains
Compared with parabolic troughs and power towers, linear Fresnel reflectors may be less efficient in generating electricity, but they may be cheaper to build. According to Wikipedia and the National Renewable Energy Laboratory, Fresnel reflectors are the third most used solar thermal technology after parabolic troughs and power towers, with about 15 plants in operation or under construction around the world. To move one small step closer to our goal of providing everyone a one-stop-shop solar modeling software program for solarizing the world, I have added the design, simulation, and analysis capabilities of this type of concentrated solar power technology in Version 7.1.8 of Energy3D.

Fig. 4: Compact linear Fresnel reflectors.
Fig. 5: Heat map view of linear Fresnel reflectors for two absorber pipes.
Like parabolic troughs, Fresnel reflectors are usually aligned in the north-south axis and rotate about the axis during the day for maximal efficiency (interestingly enough, however, some of the current Fresnel plants I found on Google Maps do not stick to this rule -- I couldn't help wondering the rationale behind their design choices). Unlike parabolic troughs, however, the reflectors hardly face the sun directly, as they have to bounce sunlight to the absorber pipe. The reflectors to the east of the absorber start the day with a nearly horizontal orientation and then gradually turn to face west. Conversely, those to the west of the absorber start the day with an angle that faces east and then gradually turn towards the horizontal direction. Due to the cosine efficiency similar to the optics related to heliostats for power towers, the reflectors to the east collect less energy in the morning than in the afternoon and those to the west collect more energy in the morning and less in the afternoon.

Like heliostats for power towers, Fresnel reflectors have both shadowing and blocking losses (Figure 3). Shadowing losses occur when a part of a reflector is shadowed by another. Blocking losses occur when a part of a reflector that receives sunlight cannot reflect the light to the absorber due to the obstruction of another reflector. In addition, Fresnel reflectors suffer from edge losses -- the focal line segments of certain portions near the edges may fall out of the absorber tube and their energy be lost, especially when the sun is low in the sky. In the current version of Energy3D, edge losses have not been calculated (they are relatively small compared with shadowing and blocking losses).

Linear Fresnel reflectors can focus light on multiple absorbers. Figure 4 shows a configuration of a compact linear Fresnel reflector with two absorber pipes, positioned to the east and west of the reflector arrays, respectively. With two absorber pipes, the reflectors may be overall closer to the absorbers, but the downside is increased blocking losses for each reflector (Figure 5).

Simulation-based analysis of parabolic trough solar power plants around the world

Fig. 1: 3D heat map of the Keahole Plant in Hawaii
Fig. 2: SEGS-8 in California and NOOR-1 in Morocco
In Version 7.1.7 of Energy3D, I have added the basic functionality needed to perform simulation-based analysis of solar power plants using parabolic trough arrays. These tools include 24-hour yield analysis for any selected day, 12-month annual yield analysis, and the 3D heat map visualization of the solar field for daily shading analysis (Figure 1). The heat map representation makes it easy to examine where and how the design can be optimized at a fine-grained level. For instance, the heat map in Figure 1 illustrates some degree of inter-row shadowing in the densely-packed Keahole Solar Power Plant in Hawaii (also known as Holaniku). If you are curious, you can also add a tree in the middle of the array to check out its effect (most solar power plants are in open space with no external obstruction to sunlight, so this is just for pure experimental fun).
Fig. 3: Hourly outputs near Tuscon in four seasons

Fig. 4: Hourly outputs near Calgary in four seasons
As of July 12, I have constructed the Energy3D models for nine such solar power plants in Canada, India, Italy, Morocco, and the United States (Arizona, California, Florida, Hawaii, and Nevada) using the newly-built user interface for creating and editing large-scale parabolic trough arrays (Figure 2). This interface aims to support anyone, be she a high school student or a professional engineer or a layperson interested in solar energy, to design this kind of solar power plant very quickly. The nine examples should sufficiently demonstrate Energy3D's capability of and relevance in designing realistic solar power plants of this type. More plants will be added in the future as we make progress in our Solarize Your World Initiative that aims to engage everyone to explore, model, and design renewable energy solutions for a sustainable world.
Fig. 5: Hourly outputs near Honolulu in four seasons

An interesting result is that the output of parabolic troughs actually dips a bit at noon in some months of the year (Figure 3), especially at high altitudes and in the winter, such as Medicine Hat in Canada at a latitude of about 51 degrees (Figure 4). This is surprising as we perceive noon as the warmest time of the day. But this effect has been observed in a real solar farm in Cary, North Carolina that uses horizontal single-axis trackers (HSATs) to turn photovoltaic solar panels. Although I don't currently have operation data from solar farms using parabolic troughs, HSAT-driven photovoltaic solar arrays that align in the north-south axis work in a way similar to parabolic troughs. So it is reasonable to expect that the outputs from parabolic troughs should exhibit similar patterns. This also seems to agree with the graphs in Figure 6 of a research paper by Italian scientists that compares parabolic troughs and Fresnel reflectors.

The effect is so counter-intuitive that folks call it "Solar Array Surprises." It occurs only in solar farms driven by HSATs (fixed arrays do not show this effect). As both the sun and the solar collectors move in HSAT solar arrays, exactly how this happens may not be easy to imagine at once. There doesn't seem to be a convincing explanation in the Internet forum where folks discussed about it. Some people suggested that the temperature effect on solar cell efficiency might be a possible cause. Although it is true that the decrease of solar cell efficiency at noon when temperature rises to unfavorable levels in the summer of North Carolina can contribute to the dip, the theory cannot explain why the effect is also pronounced in other seasons. But Energy3D accurately predicts these surprises, as I have written in an article about a year before when I added supports for solar trackers to Energy3D. I will think about this more carefully and provide the explanation later in an article dedicated to this particular topic. For now, I would like to point out that Energy3D shows that the effect diminishes for sites closer to the equator (Figure 5).

Designing panda solar power plants with Energy3D

Fig. 1: Panda power in Energy3D
Fig. 2: Panda power in Energy3D
A Panda-shaped photovoltaic (PV) solar power plant in Datong, China recently came online and quickly went viral in the news. While solar power plants in cute shapes are not a new thing (I blogged about the Mickey Mouse-shaped solar farm in Orlando, FL about six weeks ago), this one drew a lot of attentions because the company that built it, Panda Green Energy Group, is reportedly planning to build 100 more such plants around the world to advertise for renewable energy. According to the company's website, the idea of building Panda-shaped solar power plants originated from Ada Li, a student from Oregon Episcopal School. Li proposed her idea at the COP21 Conference in Paris.

The construction of the 100 MW Datong Panda Solar Power Plant began on November 20, 2016. It is expected to generate 3.2 billion KWh in a life span of 25 years. The plant consists of two types of solar panels of different colors: black monocrystalline solar panels and white thin-film solar panels. The two types form the characteristic shape and pattern of a giant panda, the national treasure of China and the logo of the World Wildlife Fund. Considering the number of people who complain about solar power plants being eyesores in their neighborhoods, these attempts by the Panda and Micky Mouse solar farms and their future cousins may provide examples to mitigate these negative perceptions.

Fig. 3: A close-up view of Panda power.
Fig. 4: A close-up view of Panda power.
One of our summer interns, Maya Haigis, who is a student from the University of Rochester, spent a couple of hours to create an Energy3D model of the Datong Panda Solar Power Plant after I shared the news with her today. The power plant is so new that Google Maps currently show only a picture of it under construction. So Maya went ahead to draw the power plant based on an artist's imagination taken from the news. Her design ended up using about 34,000 solar panels. To make it look like a real giant panda with its trademark black and white fur, I had to quickly add a light gray color option for solar panels in Energy3D. Maya's work came out to be amazingly realistic (Figures 1 and 2). This is even more remarkable considering that Maya had no prior experience with Energy3D.

Panda Green Energy said in the press release that they designed the power plant also for the purpose of engaging youth to join the renewable energy revolution. They are planning to reach out to schools for student site visits. There is also a plan to make the power plant a tourist attraction. I am not sure people would pay to go there to see it. But with Energy3D, we can imagine the experience by taking a virtual tour with the 3D model (Figures 3 and 4). The engineers among us can run Energy3D simulations to analyze its performance and investigate whether such an effort makes scientific sense.

So what about inviting children all over the world to "paint" the brownfields that have scarred our planet with this kind of good-looking solar power plants using Energy3D as a "solar brush?" Welcome to our Solarize Your World Initiative!

Energy3D turns the globe into a powerful engineering lab for everyone

Fig. 1: Dots represent regions supported in Energy3D.
Many of the readers of my blog may not know Energy3D is, in fact, also a Google Maps application. Energy3D allows users to import a satellite image of a site through the Google Maps API as the "ground image" in its 3D coordinate system, on top of which users can draw 3D structures such as buildings or power plants. Built-in simulation engines can then be used to test and analyze these structures without having to switch to another tool and leave the scene (something known as "concurrent design" in the CAD industry). These engines use large geographical and weather datasets for the site as inputs for simulations to accurately take environmental factors such as air temperature and solar radiation into account. As the climate is probably the single most important factor that drives the energy usage in buildings where we live and work, it is important to use weather data from a typical meteorological year (TMY) in a simulation. If no weather data is available for the site, Energy3D will automatically select the nearest location from a network of nearly 400 supported worldwide regions (Figure 1) when you import the satellite image from Google Maps. The following table lists the numbers of regions in 75 countries that are currently supported in Energy3D. The United States is covered by a network of 164 nodes. So if you are in the United States, you will have a better chance to find a location that may represent the climate of your area.

Afghanistan 1 Algeria 6 Argentina 3
Australia 5 Austria 1 Belarus 1
Belgium 1 Belize 1 Brazil 5
Brunei 1 Canada 10 Chile 12
China 31 Colombia 2 Costa Rica 1
Cyprus 2 Czech 1 Denmark 1
Egypt 1 Finland 1 France 8
Germany 12 Greece 2 Guatemala 1
Hungary 1 Iceland 1 India 4
Indonesia 1 Iran 3 Iraq 1
Ireland 1 Israel 1 Italy 4
Japan 6 Jerusalem 1 Jordan 1
Kenya 1 Kuwait 1 Lebanon 1
Madagascar 1 Malaysia 2 Mexico 3
Morocco 3 Nepal 1 Netherlands 1
New Zealand 2 Norway 1 Pakistan 2
Panama 1 Peru 1 Philippines 1
Poland 7 Portugal 2 Qatar 1
Republic of China 1 Romania 1 Russia 3
Saudi Arabia 2 Serbia 2 Singapore 1
South Africa 5 South Korea 2 South Pole 1
Spain 8 Sri Lanka 1 Sweden 1
Switzerland 3 Tanzania 2 Thailand 1
Turkey 3 UAE 1 Ukraine 1
United Kingdom 5 United States 164 Vietnam 1

Fig. 2: Solar sites in Fitchburg, MA.
Energy3D's capability of turning Google Maps into a gigantic virtual engineering lab has tremendous potential in STEM education and energy revolution. It allows students to pick and choose sites for designing renewable energy and energy efficiency solutions that are most relevant to their lives, such as their home and school buildings (Figure 2). It gives students an authentic tool that supports them to scientifically investigate all sorts of possibilities to design a more sustainable world and effectively communicate their ideas to the public. And, most importantly, with Energy3D being a free tool that anyone can use at zero cost, this can happen at the global scale to engage every student in the world to act now and make a difference!

This global vision is not new. Back in 1995, the National Science Foundation funded my colleagues Boris Berenfeld, Bob Tinker, and Dan Barstow, who were at TERC at that time, a grant to develop a curriculum that they touted as the Globe Lab. The Global Lab Curriculum meant to provide an interdisciplinary, one-year course at the secondary level that supports science standards and school reform through intercultural, scientifically meaningful, and collaborative student investigations in environmental studies. Students were given the opportunity to experience all aspects of genuine scientific research: problem identification, background study, project design, collaboration, data analysis, and communication.

Fig. 3: Solar power plants around the world.
More than 20 years later, technology has advanced so much that we now have many more resources and tools to rethink about this idea. With Google Maps and weather data for countless regions in the world, Energy3D is poised to become a true example of Globe Lab for science and engineering. The integration of the software and our Solarize Your World Curriculum with the current, unstoppable waves of renewable energy innovation and movement worldwide will create numerous exciting possibilities for youth to become truly involved and engaged in shaping their world and their future (Figure 3). While we undertake this grand challenge, it is utterly important to keep in mind that renewable energy does not just stand for some kind of green ideology related only to potential tax hikes -- it also represents trillions of dollars worth of business opportunities and investment in the coming decades committed by almost all governments on the planet to revamp the world's energy infrastructure to provide cleaner air and healthier environment for their citizens. Given this level of global significance, our work will only become more essential and the implications will only become more profound.

As we are mourning the loss of Bob Tinker, one of the architects of the Global Lab Curriculum, carrying on this line of work will be the best way to remember his visions, honor his contributions, and celebrate his life.

Remembering Robert F. Tinker

Concord Consortium Senior Research Scientist Sherry Hsi remembers our founder Bob Tinker who passed away on June 21st. For more personal stories about Bob and his impact, and to share your own, visit

Barbara, Bob, and Sherry

The Concord Consortium East Coast Office – Me, Bob Tinker, and Barbara Tinker, August 2016

There are few times in the world when you can say you met a person who has changed your life. I’ve had the benefit of many wonderful mentors in my life, but Bob Tinker was the mentor who was my academic non-academia father. In 1996, I was in graduate school at UC Berkeley when I first met Bob. Marcia Linn brought me to SRI International where Roy Pea was convening different stakeholders to share the possible formation of a center for innovative learning technologies. Bob was so enthusiastic and energetic about ideas. Unlike others in the room, Bob wasn’t wearing a suit or tie. He was wearing a vest adorned with buttons, one of which read “Go VHS!” (for Virtual High School). He looked more like an activist. He was fighting for social justice, equal opportunity, and science education.

Bob invited me to visit the Concord Consortium shortly after the nonprofit opened on 37 Thoreau Street in Concord, Massachusetts. This is where I first met Ray Rose, Sarah Haavind, Bruce Droste, Carolyn Staudt, George Collison, and other education technology thought leaders. Netscape Navigator was two years old, yet the team was already implementing a model international online STEM professional development program for teachers and architecting the first virtual high school.

That was just the beginning of a wonderful adventure and mentorship. Bob and I would chat about crazy ideas like putting wireless cameras on birds and nestboxes, using mobile devices for citizen science, or designing smart museum exhibits that would be aware and responsive to visitor interactions. He would share with me drafts of how an idea – always in his signature blue Palatino font – would be iteratively shaped into a winning proposal. He showed how the most daunting and intimidating problems could be made accessible if you were willing to go back to core ideas, build models, and tinker a while without the fear of failure.

During my postdoc with the Concord Consortium and the Center for Innovative Learning Technologies, we explored ways to design and scaffold science inquiry using probes and handhelds in creeks and watersheds. We also sparked and seeded projects to grow the capacity of educational mobile STEM designers by hosting a design competition at the Exploratorium. (The winning app simulated the results of cross-breeding different fish on Palm Pilots.) Bob joined remotely to the live webcast by telephone. I remember how his super amplified voice boomed over the audience like a television voice from God, enthusiastic about the potential that collaborative learning and mobile devices could have on education.

Bob was the reason I left K-12 classroom research to work at the Exploratorium. He spent a few weeks of of the year in 1998 as an Osher Fellow when the museum was led by Goery Delacote, fellow physicist. He contributed to ideas during the formation of the Center for Media and Communication where I subsequently accepted a research position. He and Rob Semper asked what-if questions around the possibility of supporting deeper visitor engagement within the museum and extended science learning beyond. What if the whole museum had ubiquitous wireless access and fast networks for media sharing? Imagine that when 802.11b was new! This led to the Electronic Guidebook Project and a strand of early experiments to test inquiry using handhelds, RFID, cameras, and beacons with exhibits. Today, this pioneering work continues to re-emerge in different forms across many museums.

Bob was more than an academic mentor. He and his wife Barbara invited me into their home, lifted my spirits when life got tough, and pushed me back out into the world. Our most recent collaboration was working together on an NSF-funded project to bring Internet-of-Thing sensors and actuators into laboratories for high school biology to support science and engineering practices together with computational thinking. This brought me back to the Concord Consortium, but this time, in the West Coast office. Unlike when we first met, high-speed multi-site web video conferencing was now possible with a single click. The Maker movement now gave us so many low-cost DIY options to play with. We spent the last year connecting and chatting by Zoom from his workshop in Amherst.

I will miss his chortling, his outbursts about Reagan, his spreadsheet genius, his photography of nature, and his genuine care in all people. I enjoyed chasing ideas and money together, but my favorite memories are seeing him race down Pier 15 with my youngest son Lucas to see fog appear, hearing him hum and wash the dishes while Barbara and I played Schubert after dinner in Carlisle, and sneaking out of a PI meeting for a moment to watch a rainbow form right after a rain shower. He was always willing to share the last piece of toffee or ask for two spoons when he ordered dessert.

Bob – wherever you are, I hope you are flying high. Thanks for helping me grow. You gave me so many gifts and words of encouragement along the way. I feel lucky that our paths crossed in this large chaotic universe. You are one of a kind. I miss you terribly.

VHS Faculty

VHS online faculty: Bob McLean, Ray Rose, Bruce Droste, Me, Sarah Haavind and others waiting to meet Senator John Kerry October 1997.

Exploratorium Palace

Bob Tinker with Bernard Osher and Sally Duensing at the Exploratorium Palace of Fine Arts in 1998. Photo credit: Ron Hipschmann

Center for Innovative Learning Technologies

Center for Innovative Learning Technologies created in 1997. Slide credit: Roy Pea

Center for Innovative Learning Technologies

Center for Innovative Learning Technologies created in 1997.

Barbara and Bob Tinker

My academic non-academia parents Barbara and Bob Tinker at Aaron’s wedding in 2006.

Handheld Design Awards for Education

Live webcast of the Handheld Design Awards for Education at the Exploratorium, San Francisco Palace of Fine Arts, 1999.

Judging and handheld demonstrations at the Exploratorium in 1999

Judging and handheld demonstrations at the Exploratorium in 1999. Left: Phil Vahey, Justin Manus, Jeff Hawkins, Me; Right: Stephen Bannasch and Carolyn Staudt demoing probeware from the Concord Consortium

Marcia Linn and Bob Tinker

Marcia Linn and Bob Tinker at a Technology-Enhanced Learning in Science (TELS) event, Washington, D.C.

A typical web video conference

A typical web video conference when collaboratively working through hard problems together – Robert Tinker, Me, Hee-Sun Lee, and Chad Dorsey – October, 2016.

Bob Tinker at the March for Science

Bob Tinker at the March for Science in Amherst, MA – April 22, 2017. Photo credit: Barbara Tinker

Modeling parabolic troughs in Energy3D

Fig. 1. The absorber tube of a parabolic trough
A parabolic trough is a type of concentrated solar collector that is straight in one dimension and curved as a parabola in the other two, lined with mirrors. Sunlight that enters the trough is focused on an absorber tube aligned along the focal line of the parabola, heating up the fluid in the tube (Figures 1 and 2). If the parabolic trough is for generating electricity, the heated fluid is then used to vaporize water and drive a turbine engine. A power plant usually consists of many rows of parabolic troughs.

Fig. 2. A view from the absorber tube.
Parabolic troughs are another common form of concentrated solar power (CSP), in addition to solar power towers that Energy3D has already supported (there are two other types of CSP technologies: Dish Stirling and Fresnel reflectors, but they are not very common). According to Wikipedia, there are currently more parabolic trough-based CSP plants than tower-based ones.

In the latest version of Energy3D (V7.0.6), users can now add any number of parabolic troughs of any shape and size to design a solar thermal power plant.

Fig. 3: Parabolic troughs at different times of the day

Parabolic troughs are most commonly aligned in the north-south axis so that they can rotate to track the sun from east to west during the day. This kind of trackers for parabolic troughs works in a way similar to the horizontal single-axis tracker (HSAT) for driving photovoltaic solar panel arrays. You can observe their motions when you change the time or date or animate the movement of the sun in Energy3D. Figure 3 illustrates this.

Like photovoltaic solar panel arrays, parabolic troughs have the inter-row shadowing problem as well. So the distance between adjacent rows of parabolic troughs cannot be too small, either. But unlike solar power towers, parabolic troughs do not have reflection blocking issues among mirrors. Figure 4 shows this.

This new addition greatly enhances Energy3D's capability of modeling CSP plants, moving the software closer to the goal of being a one-stop shop for exploring all sorts of solar solutions. In the coming weeks, we will start to build 3D models for parabolic troughs in the real world.
Fig. 4: Inter-row shadowing in parabolic trough arrays

Robert F. Tinker (1941-2017)

Concord Consortium Senior Scientist Charles Xie remembers our founder Bob Tinker who passed away on June 21st. For more personal stories about Bob and his impact, and to share your own, visit

It is in deep sadness that we mourned the passing of Dr. Robert Tinker on June 21, 2017. Bob was the founder of the Concord Consortium and the Virtual High School. For 18 years, he had been my mentor, friend, and supporter. It is hard to accept the fact that he is no longer with us.

My collaboration with Bob began in 1999, when I was doing a term of postdoc in the field of computational biophysics at the newly-established University of Cyprus. My job was to write computer code to simulate molecular motion and quantum transport in proteins. As it is difficult to imagine these nanoscopic processes from raw data generated in simulations, I had to resort to developing real-time, interactive visualizations of simulations so that I could make sense of the results. It was at this point that our trajectories merged. Around that time, Bob and colleague Dr. Boris Berenfeld just got a grant from the National Science Foundation to develop a tool that can visualize the motions of molecules and allow students to mess with them, hoping to create a powerful virtual "microscope" that can bring the obscure molecular dynamics to life on the computer screen for everyone. While Boris was surfing the then-barren Internet to find who had done what in this tiny niche, he came across my Java Molecular Dynamics applet that I created for the purpose of teaching myself Java while experimenting with interactive molecular dynamics. Boris, Bob, and Barbara (Bob's wife) immediately realized that the applet was exactly what they were looking for. After a few rounds of email exchanges, they hired me as a consultant for the project.

While we made progress on the development of what became the Molecular Workbench software later, the plan to employ me as a staff scientist at the Concord Consortium didn't go so well. For some reason, I couldn't come to the U.S. for a job interview (there was no video conference software at that time and it costed more than $3 per minute to make an international call). So Bob decided to stop by Cyprus on his way to an international conference in Israel to make sure that I wasn't just a cat that happened to know how to hit the keyboard in the right places. Even though I didn't know much about the American culture back then, the language of science needed no translation. So we hit it off at the meeting (except that it was kind of weird that the interviewee was actually the host and the interviewer was actually the guest). I made sure that he had enough authentic Mediterranean meze platters and got a chance to submerge himself in the pristine water of the Eastern Mediterranean Sea before he headed back to the States.

I arrived in the U.S. at the end of 2000, basically having nothing but a suitcase. Bob and Barbara welcomed me with an open house and gave me a room to stay for a while until I could find a place of my own. In the next eight years until he "retired," I was fortunate enough to be able to talk to him almost every workday as our offices were right next to each other. As we all remember, he was always optimistic, even in dark times such as September 11, 2001. As the years went by, funding at the Concord Consortium went up and down, but he was such a gifted grant writer that he could always manage to grab some money to keep me focused on the Molecular Workbench project until I became fully independent and found my own path and passion. After he and Barbara retreated to their retirement home in Amherst, they continued to invest their time and energy in the future of the organization. Bob went on to pen many proposals and secured a series of large grants to fund important work at the organization. Unlike many people who think programming and tinkering are "low level" jobs that the Principal Investigators should not have to do, Bob had always been creating his own prototypes and conducting his own experiments all the time to get firsthand experiences. This is probably the reason why he was so insightful with his ideas -- one cannot possibly have a deep understanding about the world if one does not bother to explore in it. He just loved science, programming, and teaching so much that he never stopped learning, thinking, and working until his final days. It is very hard for me to hold back my tears while writing about his last request to me just a few weeks ago, asking me to carry on some work on electronics that he couldn't complete because of illness. With that, he had completely dedicated his entire life to STEM.

Bob's vision about STEM education always put innovation first. He had transcribed the DNA of innovation into the Concord Consortium. His spirit had translated into a culture of innovation that is driving our research and development. With many new emerging technologies, the future ahead of us is full of exciting opportunities. With the combined power and promise of the Internet of Things (IoT), artificial intelligence (AI), and mixed reality (VR/AR/MR), the next decade will undoubtedly bring a new wave of innovation to propel STEM education to a higher level. As a pioneer of probeware for science education who completely understood the pivotal importance of sensors in IoT systems and embedded intelligence, Bob would have been thrilled to set out to explore these new territories with us.

Khi Solar One

Khi Solar One (KSO) is a 50 MW solar power tower plant located in Upington, South Africa, which was commissioned in February, 2016. KSO has 4,120 heliostats on 346 acres of land. Each heliostat is as large as 140 square meters, reflecting sunlight to a tower as tall as 205 meters. KSO has two hours of thermal storage. The power plant is expected to generate a total of 180 GWh per year.

A low-resolution simulation of Energy3D predicts that on February 28 (close to when the Google Maps image was most likely taken) and June 28 (a winter day in the southern hemisphere), the total daily input to the solar tower (not the output of electricity generated by the turbines) is about 2.6 MWh and 1.9 MWh, respectively, as is shown in the graphs below.

The Energy3D model of the KSO can be downloaded from this web page, along with other solar power plants.

Creating computer models for all solar thermal power plants in the world

Fig. 1: Energy3D models for six solar power towers
Fig. 2: The Gemasolar Plant
One of the unique features of Energy3D is its ability to model, design, and simulate solar power towers. Figure 1 shows the Energy3D models for six solar power towers: Gemosolar (Spain), PS10 (Spain), PS20 (Spain), Greenway (Turkey), Themis (France), and Badaling (China). To support the research and development on concentrated solar power (CSP) -- a solar power solution alternative to photovoltaic (PV) arrays that may be able to provide some baseload capacity, I have been working on creating a library of 3D models for all the existing and planned solar thermal power plants in the world. The ultimate goal is to develop Energy3D into a versatile CAD tool for all forms of CSP (and PV), based on accurate simulation of existing plants first. The acquisition of the capability of reliably modeling both CSP and PV will enable Energy3D to truly support our Solarize Your World Initiative.

Fig. 3: The Gemasolar Plant
Fig. 4: The Gemasolar plant (June 30)
This article shows a bit of progress towards that goal. I have recently added in Energy3D weather data for scores of sites that already have CSP plants or are planning to build CSP plants. Many of these new sites are in Africa, China, Europe, and South America (some of them were requested by our users in Algeria and Chile). These newly added locations bring the total number of sites supported in Energy3D to more than 250. This growing network should provide you weather data that are approximately applicable to your site (but let me know if your site is not currently covered by Energy3D to your satisfaction). When you import your Earth view in Energy3D, the software will automatically choose the supported location that is closest to your site. If there is already a power tower, you can use the length and direction of its shadow in the picture to estimate the date and time when the picture was taken -- this can be done by turning on the shadow and adjusting the date and time spinner of Energy3D until the calculated shadow approximately aligns with the real shadow. After this is done, the heliostats that you add to the scene will approximately point to the same direction as in the image.

In this article, I picked the impressive Gemosolar Thermosolar Plant near the city of Seville, Spain as a showcase. The plant has 2,650 heliostats on 520 acres of land, each of which is as large as 120 square meters. The tower is 140 meters tall. The annual output is approximately 110 GWh. With molten salt tanks, it can store up to 15 hours of energy. Using a low-resolution setting, it takes Energy3D 5-10 minutes to complete a daily simulation and up to a couple of hours to complete an annual simulation. If you can afford to wait longer, you can always increase the simulation resolution and improve the accuracy of results (e.g., more points on the reflectors better account for blocking and shadowing losses).