Illuminating through solar energy

By Aurangzeb Soharwardi

The government and Pepco are making all possible efforts to exploit maximum electricity generation sources to bridge the existing demand and supply gap. The electricity demand has risen to almost 17,000 mw in recent days owing to huge domestic, industrial, commercial and agricultural consumption. Particularly, the extensive use of home appliances has considerably enhanced electricity demand. This situation has led to the dire need of using alternate sources of energy, mainly the solar energy.

The earth receives an incredible supply of solar energy – the sun provides sufficient energy in one minute to meet the world’s energy demand for a full year. Solar energy is produced by the sunlight and not the heat and is based on the production and function of solar cells which are called photovoltaics (PV); the word Photo meaning light and voltaic electricity.

The life of a solar panel is approximately 20 to 25 years. In Pakistan, only three energy sources, i.e. gas, oil and hydro, account for 93 per cent of the total primary energy supplies of 51 MTOE (2003-04). The share of coal in primary energy is very low – only 6 per cent. The share of nuclear power in total energy supply is only 2.2 per cent, which is very low as compared to 30 per cent in Western Europe and 19 per cent each in North America, and Eastern Europe. The power sector in Pakistan is a mix of hydel and thermal units dominated by two vertically integrated (in generation, transmission and distribution) public sector utilities; Water and Power Development Authority (Wapda) /Pepco and Karachi Electric Supply Corporation (KESC). In addition to these, there are two nuclear power plants; Kanupp and Chanupp, and a number of independent power producers (IPPs) and small power producers (SPPs) established since 1994. Today many rental power plants are on their way to meet Pakistan’s electricity requirements.

Today's solar energy technology has evolved and solar projects are appearing in both developed and developing countries. Solar powered lighting systems can be used on streets, highways, parks, parking lots, airports, docks, residences, particularly in residential flats, and many civil and military uses. Solar street lights were initially used in areas where electricity was not always available, such as in remote or disaster hit areas. Street lights using solar technology can be quickly and easily deployed and can give years of reliable and maintenance-free operation.

Solar lights are full of electronics. The solar panel converts the sun's energy to DC electricity. Voltage is then regulated to a specific value by an electronic circuit to charge the battery. Solar lighting systems can be implemented in any remote location where the cost of installing power supply is too expensive or problematic. Traffic road management systems have begun to spread in some places. Airports, as well are big consumers of solar runway lights. A growing number of solar street lighting projects are running in Africa, Asia and the Middle East, while pilot projects are being run in some European and US cities. Well designed solar street light systems can provide an excellent alternative to traditional electric street lighting, in addition to significant energy and maintenance savings.

Pakistan has made considerable progress in solar system development. Realizing the importance of technology and the abundance of solar energy in Pakistan, AEDB has taken the initiative of indigenous development and promotion of these types of power plants. Presently, AEDB is installing three solar thermal power plants of 10-35 kwe for demonstration purpose. These plants will be made operational at College of Electrical and Mechanical Engineering, Rawalpindi and then they will be installed at suitable locations for rural electrification. After the successful demonstration of these plants, the private sector will be facilitated to install 50-100 mwe solar thermal power plants. Due to global warming, areas of Thar, Balochistan, Sindh and Punjab are getting hotter, so in these areas, solar panels can be very useful and they'll produce sufficient amount of electricity and reduce the heat radiation spreading on the landmass. Furthermore, the southern provinces receive a lot of heat throughout the year; solar energy can be saved and exported to countries that desperately need energy in winters to keep their heating systems functioning.

As compared with other technology mediums for producing power, solar technology is truly ‘environment friendly,’ because it is generated from the sun. Many technologically advanced systems like, photovoltaic module component, solar air heating system, etc. can be used to meet energy needs.

Presently in Pakistan, almost 600 houses are being electrified through solar energy and efforts to put home appliances are also underway. LED technology is increasingly being used in streetlight applications due to its longer life and energy-saving qualities. Compared to an HPS streetlight, an LED streetlight will last up to 50,000 hours, significantly reduce light pollution and save energy and will also be better equipped to withstand extreme hot and cold temperatures, which makes it suited for outdoor use. Moreover, LED streetlight has a 100 to 1,000 times faster response, which results in sharp, pure colour.

In a project, BBE LED has installed 56W LED streetlight; LU2 in Peshawar. This is one of the most efficient models which can replace the 150w or even 250 HPS streetlight. All over Pakistan, millions of street light connections are managed by the streetlight divisions of PEPCO (Pakistan Electric Power Company). The average number of street light connections range from 25,000 to 57,000, which comes to about 2 million connections. This stupendous electricity consumption amount is a non productive burden. If the streetlights are converted to solar, it can save a considerable amount of electricity. A huge number of traffic signals along with advertising billboards are also consuming a substantial amount of electricity. The traffic flow is jeopardized once the electricity goes off, resulting in switching off of the signals. This non productive excessive use of energy has put an additional burden on the electricity generation capacity and its distribution system.

The Deputy Chairman of Planning Commission has said that the existing energy crisis could be overcome easily by converting all the streetlights, park lights and traffic signals to solar energy while chairing a meeting, organized by Pakistan Council of Renewable Energy Technologies (PCRET).The Planning Commission is working on projects which will help electrify thousands of villages every year. The Alternative Energy Development Board (AEDB) has also taken an initiative to provide villagers the comforts of lighting, cooking and water disinfection through solar energy technologies. During the previous financial years, a total of 601 villages were solar electrified in 2004-05 and about 400 villages in 2005-06 by the board. One such example is the village of Narian Khorian, where 100 solar panels have been installed by a local firm, free of cost, to promote the use of solar energy among the masses. Through these panels, the residents of 100 households are enjoying light and fan facilities.

Solar energy makes sense for Pakistan for several reasons, including the fact that 70 per cent of the population lives in 50,000 villages that are very far away from the national grid, according to a report by the Solar Energy Research Center (SERC). For Pepco, connecting these villages to the national grid would be very costly, thus giving each house a solar panel would be cost efficient and would empower people both economically and socially. It may be clarified that it is the sun’s light and not its heat that produces electricity. A very successful experiment was conducted in 2002, when the illumination of a vast public park in Gilgit city was converted to solar energy.

Similarly, Roomi park in Rawalpindi is lit up by solar energy too. All the parks in the country can be put onto solar energy, thereby saving huge amount of megawatts produced through other sources. An LVD based solar street light was erected on the 11th of March 2009 in DHA Karachi. The newly introduced LVD lighting technology possesses almost 40 per cent energy conservation compared to HPS for similar or better illumination and a much better CRI.

Many companies have been involved in Photovoltaic business in Pakistan. Complete solar systems in all parts of the country, mainly for house electrification, telecommunication, water pumping, navigation, highway communication, oil and gas fields and street lighting have been installed. Solar water heaters of 20,000 liters capacity have been installed and are in use at the Attock Oil Refineries, Rawalpindi.

We should establish not one but several factories for the manufacture of solar panels and cells in Pakistan and also encourage big construction companies to go solar while constructing mega construction projects. We have sufficient quantity of raw materials at our disposal and skilled human resources. All the concerned organizations and departments must work in complete harmony to plan and execute solar energy projects in Pakistan for optimal benefits. It will also reduce a huge burden from Pepco’s shoulders to plan, establish and maintain a vast electricity infrastructure, besides exploring electricity generation opportunities.