Yemeni researcher says solar cells can produce electricity [Archives:2007/1096/Reportage]
Almigdad Dahesh Mojalli
Dr. Marwan Dhamrin, a postdoctoral research fellow for the Japan Society for the Promotion of Science, presented research in Milan in early September regarding using solar cells to produce electricity directly from sunlight.
His research involves the quality of N-type multicrystalline silicon wafers – a key material in manufacturing transistors and integrated circuits – in solving numerous issues, including possible high solar cell conversion efficiency, using recycled silicon feedstock and its stability under sunlight.
Dhamrin says a solar cell is an electronic device employing semiconductor material to generate electricity directly from light. The first solar cells were made in the United States in the early 1950s by Bell Laboratories.
“The main semiconductor material used in solar cell industry is P-type silicon wafers,” Dhamrin explained, “however, due to strong demand for silicon from both the solar cell industry and other electronic devices industries, such as memory RAM, processors, chips and integrated circuits, silicon prices skyrocketed from $30 per kilogram to more than $100 for long term contracts and even $200 in small markets.
The researcher went on to say that the difference between N-type and P-type is in the type of the electronic minority carrier's nature to be electrons in P-type silicon and holes in N-type silicon. N-type silicon was avoided in the early stages of solar cell development due to quality degradation in space applications due to strong radiation effects.
“P-type silicon offers better quality in space applications but fails to prove the same quality in terrestrial applications to maintain higher conversion efficiency due to well-known light-induced degradation problems in typical boron doped P-type silicon.
“N-type silicon is significantly superior and now has a light-induced degradation effect which makes it a better choice for higher conversion efficiency devices. Japanese firm Sanyo just announced a world record of 22.3 percent conversion efficiency on large area N-type silicon solar cells at the same conference using relatively expensive single crystalline silicon.
“However, they're paying great attention to developing N-type multicrystalline silicon especially and they're helping our laboratory to improve its quality.”
According to Dhamrin, Sharp, one of the big producing companies, produces approximately 100 million solar cells annually, which is equivalent to at least 1 million tons of silicon. The impact of such increase is very strong and takes its toll on the final price of kilowatt-hour of electricity, he says.
“And although our target is to reduce the kilowatt hour price to that of other conventional oil-based electricity, it's very important to search for other silicon feedstock, for instance, using recycled N-type silicon from scrap material used in the semiconductor industry.”
He further noted that Sharp is the main firm producing the world's solar cells, producing approximately 17 percent of the world's total market, followed by the massive German company, Q-cell.
Sharp's 2006 production capacity was 600 megawatts equivalent to more than 100.23 million square centimeters of solar cells.
Dhamrin has received numerous awards during his study, including:
1. The Japanese Society for the Promotion of Science's Postdoctoral Fellowship Award for April 1, 2006 to March 31, 2008.
2. The Business Venture Laboratory's Postdoctoral Fellowship research grant for April 1, 2005 to March 31, 2006.
3. The 2003 Third World Conference on Photovoltaic Energy Conversion's Best Poster Award.
4. The 2005 15th International Photovoltaic Science and Engineering Conference's Best Poster Award.
5. The 2005 15th International Photovoltaic Science and Engineering Conference's Best Paper Award.
Most subjects related to suppressing the light-induced degradation of silicon solar cells.
Dhamrin says he thinks of returning to Yemen, “However, I think it's better to get the best research opportunities and explore all possible and available technologies in order to make the right technology transfer in the future. Having a doctor of engineering isn't really enough to go back and teach at Sana'a University, so one should make as many science publications and achievements as possible before returning home.
“Yemen still is far from modern technology and there's no infrastructure for the semiconductor industry. Such technology transfer requires more human and financial resources too,” he added.
Born Feb. 27, 1975 in Taiz, Dhamrin obtained a bachelor's in physics in 1998 from Sana'a University's faculty of science. Being a prominent student, following graduation, he was appointed a demonstrator in the university's physics department until early 1999.
In 1999, the Japanese government approved his application for the prestigious Monbokagakusho Scholarship, considered at the same level as the United States' Fulbright scholarship, to pursue higher education. He earned a master's in electronic and information technology from the faculty of technology at Tokyo University of Agriculture and Technology.
Dhamrin is enrolled in the doctoral program at the same university working in the semiconductor engineering field and specializing in how to improve solar cell conversion efficiency.
“I'm now a postdoctoral research fellow for the Japan Society for the Promotion of Science. The society approved my research application and science grant, along with another 300 scientists from around the world, from among 5,000 applications.”
Dhamrin continued, “The JSPS Fellowship is considered the top science opportunity in Japan. They gave me a 12 million Yen two-year science grant to continue researching at the same university.
“My family must put up with my lengthy research, where I spend most of my time in the laboratories of universities or private firms,” he concluded.
Traffic officers treat offenders badly, report says
By: Hamed Thabet
A recent report by a local non-governmental organization alleges that the Interior Ministry's Public Traffic Department detains drivers involved in traffic incidents for weeks without charge.
Issued in late September by the Democracy Awareness and Human Rights Development, the report said the traffic department has detained 60 Yemeni drivers, most without charge.
Vehicular accidents are common in Yemen, injuring many and killing others as a result. Drivers who do such offenses are imprisoned, but some are detained without clear charges.
“Citizens sometimes remain in traffic department jails more than two months and some are jailed without charge. This is illegal,” the report adds.
According to the report, senior traffic officers may illegally send offenders to traffic department jails. “Senior officers may send whomever they want to jail, even if the individual isn't guilty. The funny thing is that many prisoners don't know why they're detained,” the report notes.
It cites examples of drivers detained without charge. One such prisoner, Abdulmalik Al-Feel, recounted, “A beggar fell in front of my motorcycle, so I took the individual to the hospital. What did I get in return? Traffic officers were waiting for me and put me in jail for 10 days.”
Another prisoner, Wahib Al-Thabhani, said, “An individual helped an injured man hit by a car and took him to the hospital after the car's driver fled. When traffic officers arrived, they took him to jail where he remained three days for investigation.”
However, traffic department officials maintain that there are no prisoners without charges. Traffic department head Yahya Shobail told the Yemen Times that offenders do not remain in jail for many days and are released shortly.
He said, “We don't jail anyone without reason. Drivers who cause accidents are jailed for investigation. When victims are badly injured by drivers and must be hospitalized, in this case, drivers remain in prison a few days by order of the traffic department or the attorney general.”
Shobail made it clear that whenever drivers cause accidents, an investigation must be conducted. “These steps are normal everywhere in the world. Drivers must be held responsible for their behavior, which isn't our problem. We can't call them prisoners because they remain in detention for only a short time, usually less than a day,” he noted.
According to the traffic department, those under age 18 aren't detained. “In exceptional cases, we place those under age 18 in a traffic office until his parents or a responsible guardian comes to us,” Shobail explained.
He added, “Our first goal is to serve citizens and look after their problems in order to solve them as soon as possible. In many cases, drivers make mistakes, but never consider themselves guilty. For sure, whoever is jailed will say that he isn't guilty and that we have jailed him for no reason.”
The report also noted that the condition of such jails is very bad, with rooms in poor condition and dark because they have no windows. “The conditions of traffic department jails are wholly unsuitable for anyone, even for a few minutes,” it stated, adding that rooms are dirty and detainees suffer from the stench coming from them.
According to the report, there are two adjoining rooms and a very small hallway with one bathroom for the two rooms. Each room's capacity is a maximum 10 individuals; however, the number of detainees exceeds 10.
Additionally, the report said, “The condition in the jail is unhealthy. Detainees don't receive any health care due to carelessness on the part of concerned authorities.”
What's even more awful, the report went on to say, is that prisoners aren't allowed to use their phones, which is the only way to contact their families.
After obtaining permission from its officials, the Yemen Times visited a traffic department jail to interview detainees being held there on various charges about the treatment they have received. There were 42 individuals in the two adjoining rooms.
Wael Mahfouz Al-Qadasi, a 23-year-old driver from Sana'a, said, “I hit a man with my truck and he's now in the hospital.” Al-Qadasi says he feels fine so far and that everything is available for him at the jail.
An 18-year-old driver jailed on a charge of killing a man with his car stated, “I feel like I'm in a five-star hotel. I'm satisfied.”
However, one driver detained at the jail said, “Of course, people will tell you with a big smile that everything is fine and they love staying at the jail because they have no other alternative. If they did say anything else, they'd get in trouble. I'm saying this because I was there once.”
Shobail denies the report's claims. “It's illegal to treat citizens as the report says. Detainees are treated well,” he says, adding that a telephone is available for them to call their families.
He notes that sunlight also reaches the jail's rooms. “If what the report says was true, be assured that the attorney general would punish us. Our officers don't have orders or even the authority to treat drivers badly.”