The three key elements: time, location and human

"The establishment of the work is the predestined affinity between Solarlab and Tuan An, for which Solarlab has waited for 30 years ...", that is a humourous saying of Mr. Trinh Quang Dung (in charge of Solarlab, the author of this work), a saying that speaks out all the hardness in carrying out this solar power project in Vietnam for the last 30 years.

An investment of around 2 billion dong is likely to discourage any undetermined investors, not counting the three factors of time, location and human which all contributed to the success of the work. It began in 2007 when Mai Linh Group had an intention to invest on a solar power work at the company’s headquarter situated at No.168 Hai Ba Trung.

Solarlab and Mai Linh Group studied how to design such a project; the work, however, has never been finished due to the lack of a favourable location. The Mai Linh building has changed ownerships several times and was rebuilt so no one could be sure whether it was strong enough for a grid solar power work on the top floor with total weight of twenty tons. Furthermore, at that time, grid solar power technology was still unfamiliar yet to Vietnam in particular and South East Asia in general.

Nonetheless, later on, it seemed like destiny has brought representatives of Tuan An Corporation and Solarlab together in the middle of 2009. This time, all the elements of time, place and human were perfectly favourable and the work went on smoothly. Its success affirms the position of Vietnamese solar power technology and its ability to catch up with the world standard. The “perfect time” was marked since power shortage in Vietnam created a strained atmosphere among people, while a campaign to stop global warming and reduce greenhouse gas emission had been officially announced; and renewable energy and solar power in particular were received more attention from the public. Under such condition, the Department of Science and Technology of Ho Chi Minh City joined to support the project.

Always low-price electricity

This is the first grid solar power project in Ho Chi Minh city, a collaboration of Solarlab and South Thai Ha joint stock company (in charge of manufacturing devices on the designs under technical supervision of Solarlab and Institute of physics of Ho Chi Minh city). It was launched in September 2009 and after 6 continuous months going through many hardships, the effort was paid deservingly.

The project went on very well and was finally finished on March 2010. The entire arrangement of solar power panels has total capacity of 12.6 KWp and covers the surface of the building’s top floor, an area of over 100 m2. This is the largest solar power work in Ho Chi Minh city so far. The operation room with specialized, high capacity battery of accumulators (1,600 Ah /48V) ensures a continuous source of electricity all the time, independent of the National electricity grid. Every day this system of solar power produces 70 kWh, enough to supply the demand for priority electricity (constitutes 30% of total electricity demand of Tuan An Building)

Electricity generated from the solar power panels is transformed into alternative current with PV Madicub (an electricity transformer device used for transforming solar power into normal alternative current 220V 50Hz) and then ‘stored’ with power from national grid. The preference of power usage in the whole building, however, is set to solar power. Only when there is a shortage in solar power supply, does the building need to use electricity from national power grid.

One purpose of developing solar power technology is to support the load for the national grid and enable consumers to use EVN’s electricity at peak hours with price of off-peak hours (price of grid electricity at night is only 500 dong per Kwh, while during peak hour it is about 2000 dong, calculated accumulatively).

When a power cut or an electricity wire problem occurs, the system will switch instantaneously to use backup solar power network from the 1600 Ah accumulator set, using a backup Madicub device (an electric transformer from 48 VDC to 220 VAC 50 Hz).

From 10 PM, the smart controlling system automatically switches to use national grid electricity at low price (500 dong per kWh). The excess electricity generated from solar power panels during the day is immediately stored in an electricity storing system of the work. All the activities of the system are recorded by software, then stored in computer’s hard. The data can be accessed by technicians anytime for research and testing purpose; and if necessary they can also be accessed from satellites using a Web-box device.

With this new technology of using solar power, Vietnam has registered as the sixth country in Asia mastering solar power technology, together with Japan, China, Korea, Taiwan, Thailand.

By Nguyen An