Monday, January 18, 2010
Bidirectional Solar Tracking System
Solar power is the conversion of sunlight to electricity. Sunlight can be converted directly into electricity using photovoltaic (PV).
Electro-optical solar trackers are usually composed of at least one pair of anti-parallel connected photo-resistors or PV solar cells which are, by equal intensity of illumination of both elements, electrically balanced so that there is either no or negligible control signal on a driving motor. In auxiliary bifacial solar cell, the bifacial solar cell senses and drives the system to the desired position and in PC controlled date and time based, a PC calculates the sun positions with respect to date and time with algorithms and create signals for the system control. This thesis use the combination of three methods above method in order every minute there is 90 degree incident light fall on the PV cells.
As briefly, this thesis is about a bidirectional solar tracking photovoltaic system. Bidirectional movement is being actuated by two dc motor. A H-type motor driver is designed in order to control motor in 4 mode, forward, reverse, forward breaking and reverse breaking. Motor is being controlled by a programmed PIC18F4250 that receive signal from sensors.
The motors change the altitude and longitude angle of 20 pieces series connections of PV cells, in order the sun’s incident angle is always perpendicular to the PV cells. Most of the converted energy is used to charge up batteries instead of supplying power for the control and driving system. Dimension of the PV cell is 15cm X 30cm, total 20 pieces PV area is 0.9m.
Dimension of mirror is 15cm X30cm, total 30 piece mirror area is 1.35m. Solar concentration ratio is 2suns. V of solar cell is about 16V and 130mA, hence nearly 2W per piece. Estimated cascade 20pieces of PV will give 35W due to several power losses in the circuitry and other relevant factor.
Increase demand for green tech to bring down cost
Increase demand for green tech to bring down cost
By DHARMENDER SINGH
PUTRAJAYA: Malaysia will have to first have a plan to increase demand for renewable energy sources like solar panels if it is to truly promote the use of cheaper and more environment friendly power sources, said Energy, Green Technology and Water Minister Datuk Peter Chin Fah Kui.
Chin said the Government was serious about pursuing the use of renewable and efficient energy sources and the formation of the National Technology Council headed by the Prime Minister himself, that would meet in December for the first time, was proof of its commitment.
However the price of alternative power sources like solar or photovoltaic (PV) panels was still not low enough for a large portion of the people in Malaysia to use because, despite having several large manufacturers of such panels, local demand was still too small to allow for mass production.
“The solar PV industry can generate cumulative business revenues of more than RM560bil by 2020 or 4% of the national GDP (Gross Domestic Product), as well as turn Malaysia into a knowledge-based and high-technology manufacturing and services base capable of creating up to 100,000 jobs.
“But the only way to increase demand and allow mass production is by increasing awareness among the public on the benefits of using alternative power sources as well dispelling misguided notions that such options are expensive and low in efficiency,” he told a press conference after launching the Second National Photovoltaic Conference 2009 here on Tuesday.
Chin said progress had been made in the use of renewable energy in Malaysia despite having listed it as fifth fuel source in 2001, but things were set to change further with the allocation of RM1.5bil for green technology under Budget 2010.
“We have also finalised the new National Renewable Energy Policy and Action Plan which we will unveil after it is endorsed by the Cabinet, hopefully next month.
“With this I hope renewable energy will play a prominent role in our future energy mix and contribute significantly to our future economic development,” he said.
He said the Government was aiming to have 5% of the power in the country coming from various renewable sources, apart from hydro-electric plants, by the year 2050.
While it seemed like a modest target, he said, the Government was taking into account that it would take time for the people to turn to such power options.
World Council for Renewable Energy general chairman Dr Hermann Scheer, who was also at the press conference, said that even Germany had experienced a slow start when it first started to move towards introducing renewable energy sources several decades ago, although now it was known as one the most advanced in its use.
He said the percentage of increase in the use of PV and other sources of renewable energy would increase annually and once it had gained momentum, it would be possible to have entire communities running completely on them as could be seen in various places in Germany.
Chin said he also hoped that developers would play a part in promoting the use of solar panels by installing them in the houses they constructed and also called on people to demand such added features when they purchased such properties.
