Natural Lights in Desert

Posted: April 5, 2011 in News and Views



Rakshanda Khowaja, Researcher

Solar systems collect energy from sunlight; thermal systems convert it to heat, while photovoltaic (PV) systems convert it to electricity. The amount of energy produced varies according to the system’s location, the time of year and the weather, although some energy is produced even on cloudy days. Solar thermal systems can be used to heat water, dry crops or cook food. Solar PV systems can be connected directly to an electricity grid when one is present, or can be used to charge batteries to store power until it is needed. Typical applications for off-grid solar PV include home lighting, mobile phone charging, computers, vaccine refrigerators, portable lanterns and irrigation.

The capital cost of solar PV is high compared to other renewable energy sources, although the running costs are minimal. The rapid uptake of solar PV in developed countries has been made possible by subsidies, but in developing countries, where the alternative is often kerosene or dry cell batteries, solar PV is very competitive.

The benefits of off-grid solar PV in developing countries include the avoidance of fire risk and pollution from kerosene lamps, the ability to charge mobile phones, and the provision of radio, television and computer services.

Technology background: Solar systems collect energy directly from sunlight. The energy can be converted either to heat (solar thermal) or electricity (photovoltaics, or PV). Solar thermal technology can be used to heat water, dry crops or to cook food. PV systems use solar cells that convert light into electricity. Cells are usually linked together and arranged into weatherproof modules, so they can be mounted in a place where they can be in sunlight for as much of the day as possible. Solar PV systems can be made in a wide range of sizes, from a few small cells to run a calculator to a large solar farm with hundreds of large modules. The rating of a solar PV module is given in watts-peak (Wp), which is the power generated by the module in direct sunlight of an intensity of 1 kW per square meter. Although in most places and over much of the day, the solar intensity is well below this, the efficiency of PV cells is virtually independent of solar intensity, so they continue to supply some power even at low light levels when the sky is overcast. Most of the PV in operation uses thin wafers or layers of crystalline silicon as the active material, and these technologies accounted for about 93% of the global market in 2006. The production of the silicon cells, and the silicon feedstock to make them, is growing rapidly, with new factories opening, particularly in China. There is growing interest in the use of very thin films of silicon and other materials for PV. Although these currently account for only 7% of the global market, their use is increasing rapidly, and they offer the potential for significant cost reduction as production scales up.

Off-grid systems

Solar energy, since it derives from the sun, is available only during the day and varies as the sun follows its daily and yearly cycles, as well as being affected by cloud cover. An off-grid solar PV system, therefore, usually includes batteries to store excess energy when it is available and deliver it when it is needed. An electronic charge controller prevents the batteries from being overcharged, or over-discharged, which increases their useable lifetime.

Grid-connected systems

Grid-connected PV systems do not need batteries, as they are mainly used to off-set the energy supplied by the mains electricity grid to a building, or to supply power into the grid. The electronic control for a grid-connected system includes an inverter to convert the dc power generated by the solar panels to the ac power, usually at higher voltages, required by the grid.

Use in developing countries

Solar home systems

The most commonly used PV system in developing countries is the solar home system. This consists of a solar module (at a typical rating of 35 Wp) connected to a charge controller and a battery. The system usually includes one or more lights and a socket to which other electrical equipment, such as a radio, TV or mobile phone charger can be connected. Efficient lights are always recommended for PV systems, to make best use of the limited supply of electricity. Small dc fluorescent light are available down to 3 or 4W power rating, in both tube and compact forms, and LED lights are becoming sufficiently cheap and reliable to be used as well. Although the amount of electricity supplied by a solar home system is small, typically below 0.1 kWh per day, the benefits can be significant:

Electric light avoids the fumes and the fire-risk of kerosene lamps, and gives opportunities for study, income-generating work and recreation after dark.

Radio and television provide information and entertainment.

The use of mobile phones is expanding rapidly in developing countries, and gives the possibility of communications in very remote areas without mains supply. PV phone chargers are ideal to support this communications growth, and both individuals and phone-charging businesses are using them. Large programmes have provided solar home systems in many countries, including India, Bangladesh, Sri Lanka, China and Indonesia. The most successful programmes usually run on a commercial or near-commercial basis, and programmes with substantial government funding have often been less successful.

Vaccine refrigerators

Another common use for PV is for running refrigerators, especially for vaccine storage in remote clinics. Vaccine refrigerators are designed to be very efficient, but still need at least 0.3kWh of electricity per day, so larger arrays of modules (typically 240 Wp) are used. Increased battery storage capacity is usually provided, to make sure that vaccines remain cold even if the sky is overcast for several days.

Economics

The cost of electricity from PV is high compared to other renewable energy sources. average, grid-connected systems, which – despite low running costs – gives a cost for the electricity of about 20-50p per kWh. There is currently enormous demand for PV to supply government-supported programmes in Europe, Japan and the USA, and, despite rapid growth, the supply industry cannot meet demand and as a result prices have not decreased. However, the economics of off-grid PV is very different, and in developing countries the cost of a solar home system can usually be paid back in three to five years from savings made on kerosene or dry cell batteries

Thar Desert area’s an indigenous Organization Association for Water Applied Education & Renewable Energy (AWARE) Tharparkar, in collaboration with the Pakistan Council of Renewable Energy Technologies (PCRET), has installed solar panels on an experimental basis,

To produce affordable and environment gracious electricity in District Tharparkar Province of Sindh, including the Desert area.

Solar cells or solar energy units are long lasting sources of energy that can be used almost anywhere and can be a cost effective solution to the increasing energy demands,” said Mr Ali Akbar Executive Director Association for Water Applied Education & Renewable Energy (AWARE), adding that the experimental introduction He said that with the power crisis of Pakistan deepening by the day, these solar energy panels could be a successful surrogate for furnace oil based or hydroelectricity.  The benefits of off-grid solar PV in developing countries include the prevention of fire risk and pollution from kerosene lamps, the ability to charge mobile phones, and the provision of radio, television and computer services.

In the first phase of the programme, we have introduced the solar panels at twelve 01 site, Tehsil Chacharo District Tharparkar. On top of the fact that these areas have a lot of approaching, the people of these areas have been deprived of electricity for the past 60 years,” said Mr Ali Akbar Rahimoo Researcher, he said that, although these solar panels have been installed on an tentative basis, in future, they could serve as models for the implementation of alternative energy sources. Each of these solar panels comprise of two solar plates, two power saving batteries and a charge controller. The single unit costs Rs 450,000 and can power three 20 Volt energy saver bulbs and two small wall mount fans.

The solar plates, which are installed in an open space, absorb sunlight and transmit it to the controller, which after converting the solar energy into electricity transmits it to the power saving batteries. The panels can power these five electricity gadgets continuously throughout the day and the power stored in the batteries can last for up to eight to 10 hours at night. “The introduction of these solar panels is no less than a marvel for the people of these areas who never even dreamt of having electricity in their homes,” Pakistan Council of Renewable Energy Technologies (PCRET) Mr Nadeem Zakir Highlighting the advantages of these solar panels, he said that apart from being completely environmental friendly, the panels require little or no maintenance and have a very long natural life

He said that, so far, a total of 12 panels have been installed at District Tharparkar, “The total of 12 panels, six were installed in a Masjid’s in the village Samoo Rind, one in a mosque of Charnaore village located in Karoaro, three panels installed in Village Tardos mosques and 03 has been installed at a community school of the same village, one system installed in High School Tardos , other 02 system installed in Middle School Karoaro, & Charnaore ” Mr Nadeem Zakir He further revealed that there were two categories of panels. Panel A, which has an output of 200 Watt, comes with two batteries and can power two energy savers and two wall mount fans, has been installed at the mosque, while Panel B, which has an output of 500 Watt, comes with four batteries and can power four energy savers and two wall mount fans, has been installed at the school.

 

Use in developing countries

Solar home systems

The most commonly used PV system in developing countries is the solar home system. This consists of a solar module (at a typical rating of 35 Wp) connected to a charge controller and a battery. The system usually includes one or more lights and a socket to which other electrical equipment, such as a radio, TV or mobile phone charger can be connected. Efficient lights are always recommended for PV systems, to make best use of the limited supply of electricity. Small dc fluorescent light are available down to 3 or 4W power rating, in both tube and compact forms, and LED lights are becoming sufficiently cheap and reliable to be used as well. Although the amount of electricity supplied by a solar home system is small, typically below 0.1 kWh per day, the benefits can be significant:

Electric light avoids the fumes and the fire-risk of kerosene lamps, and gives opportunities for study, income-generating work and recreation after dark.

Radio and television provide information and entertainment.

The use of mobile phones is expanding rapidly in developing countries, and gives the possibility of communications in very remote areas without mains supply. PV phone chargers are ideal to support this communications growth, and both individuals and phone-charging businesses are using them. Large programmes have provided solar home systems in many countries, including India, Bangladesh, Sri Lanka, China and Indonesia. The most successful programmes usually run on a commercial or near-commercial basis, and programmes with substantial government funding have often been less successful.

Vaccine refrigerators

Another common use for PV is for running refrigerators, especially for vaccine storage in remote clinics. Vaccine refrigerators are designed to be very efficient, but still need at least 0.3kWh of electricity per day, so larger arrays of modules (typically 240 Wp) are used. Increased battery storage capacity is usually provided, to make sure that vaccines remain cold even if the sky is overcast for several days.

Economics

The cost of electricity from PV is high compared to other renewable energy sources. average, grid-connected systems, which – despite low running costs – gives a cost for the electricity of about 20-50p per kWh. There is currently enormous demand for PV to supply government-supported programmes in Europe, Japan and the USA, and, despite rapid growth, the supply industry cannot meet demand and as a result prices have not decreased. However, the economics of off-grid PV is very different, and in developing countries the cost of a solar home system can usually be paid back in three to five years from savings made on kerosene or dry cell batteries

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Comments
  1. (In response to Ali Palh’s facebook message)
    It’s true that Solar PV can be used to provide electricity in Thar desert. Such systems are widely deployed in Germany, especially on-grid system as the government had once offered a huge subsidy. Majority of households in Germany managed to install on-grid system and the production of solar energy reached an extent that electricity utility companies got frightened of losing business.

    In case of Thar, since the proposed areas are not fed by commercial grid, the on-grid systems cannot be proposed. However, the stand-alone PV systems lack centralized coordination mechanism and since the house-holds lack literacy, the management and sustainability of PV systems is doubtful.

    This problem can be solved by coupling household PV systems with wireless sensor network to relay the system parameters to a control center located in nearby city, e.g. Umerkot or Mithi. The center has to be properly equipped with power system monitoring and control equipment and technical HR mobile team who can act in case of any abnormality.

    I have been much interested in promotion of solar and wind power generation for Thar, but being away and not finding enough push / pull from civil society, could not put forward proposals. If any NGO has sufficient data of the area, they are welcome to contact me via LinkedIn or email.

    • Ali Akbar says:

      Saeen,
      Namste
      Plz share ur email/contacts, we would like to share with u about wind and solar experiecnces we have and some plans.

  2. Mehrunisa says:

    Dear Khawaja
    This is really high promising for Thar and adjoining areas.
    Regards

  3. rightsnowpak says:

    In response to facebook message sent by Ali Palh;
    Seen, in the paper work mentioned is of AWARE. This have been done practically and some details also could be found on http://www.aware.org.pk AWARE Team is thankful to Ms. Khawaja for hilighting the work. Recently AWARE also has installed 16 solar PV systems for women artisans in Thar. These r for increasing working hours of artisans, providing facility to children in same home in reading and interestingly these lights also work as repeller to snakes. If u need more info plz contact http://www.facebook.com/l.php?u=http%3A%2F%2Fwww.au%2F&h=0f509

  4. AWARE’s work is really appreciable. Well done Ali Akbar Rahmoon and team!

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