August Issue 2009

It has been six months since Shahid Sayeed Khan, CEO of Indus Earth Trust, installed a hybrid system, a 1kW turbine and 1.5kW solar panels, in his house in Clifton in Karachi. It powers all the lights and fans in the house. Reema Shoaib, resident of Askari 3 in Karachi, also has a hybrid system installed in her house with a generation capacity of 1kW from the turbine and 500W from the solar panels. Her system can support 30 lights, 11 fans, three television sets, one computer and kitchen appliances such as a blender and chopper. Saif Karamali, resident of Defence in Karachi can run two television sets, one fridge, 30 lights and six fans powered by two 500W turbines.

And all these electrical appliances are run while the electricity is out.

What all three have been able to do — other than adopt an eco-friendly solution — is to rid themselves of the inconvenience and expense of operating generators, or have the UPS conk out two hours after a power outage. The turbines and hybrid systems serve as alternatives to today’s popular options: an UPS or generator.

Power generated through wind and solar energy is stored into a battery bank. Different companies use different kinds of batteries to support the wind turbine and hybrid systems, which also vary with the country the equipment has been purchased from. For every kW of power, says Mohammed Sarwar of Mesec Group, who installed the hybrid system that was bought from Germany in Reema’s house, four 200 amp batteries are required for energy storage; he advises the use of Medicell batteries. Ali Mabzi, managing director of Mabzi International Pvt Ltd, who installed the turbines bought from China in Saif’s house, says one requires four 120 amp batteries, popularly known as truck batteries, for a 1kW turbine. The backup provided by the battery bank depends on the electrical load of the house, but is estimated at five hours.

To increase backup, one may also add to the battery bank. Saif, who requires four batteries, has a custom-made six battery pack. Additionally, he also draws electricity from KESC to charge the batteries. This allows him to store more energy and run the refrigerator. “What can also happen is that if the electricity goes out, and you are using the energy stored but the wind is also blowing at the same time, energy is being consumed and generated at the same time, increasing the number of hours of backup,” says Ali. Furthermore, to run heavier appliances, says Mohammed Sarwar, a larger motor is required for the turbine. But that the house can be run on the power generated from the turbines and and panels round the clock, is a myth. Ali explains that it is a fluctuating resource: the power generation depends on how much wind or light is available in a day and how much energy the batteries can store.

However, not everyone can install wind turbines in their homes and it is strictly on an area- and house-specific basis. Going by international standards, a wind speed of 9-12 metres/second is required for a 500W-1kW turbine to function. The propeller should also be 30 feet above sea level, a height at which wind is at its optimum. Saif’s turbine is supported by an 18-foot pole whereas Shahid’s is on a six-foot pole as Clifton is on a higher terrain than DHA.

But even if the location is suitable, there are still a fair share of hurdles to be overcome. For Shahid, the electrical discharge from the turbines into the existing electrical system took some sorting out, while, for Saif, it was a case of second-time lucky before the turbines started working for him. The turbine they first got was a 2kW model. “It was not suited for a rooftop,” says Saif. “The turbine in itself was good, but the inverter — which charges the battery and regulates the power to your house — was faulty and thus unable to deliver the power produced.” Such a large unit also produced vibrations that passed through the house, and the propellers were noisy, a nuisance to neighbouring houses.

Saif says the installation of the turbines has aroused the interest of people living in his neighbourhood, and some have even come to inquire and get details about them, but, when most hear of the cost, they turn away. The prices of these units vary depending on which country they are imported from and what the size of the turbine or solar panel is. “You can purchase [the turbines] from China, Holland, Germany, US, and there are agencies locally that can supply them,” says Shahid.

“For a 1kW wind turbine with installation,” says Sarwar, “we charge a sum of $3,500 (approx Rs 280,000).” Ali quotes the price of a 500W turbine at Rs 75,000. The prices of batteries range anything from Rs 10,000-20,000, depending on the type (wet, dry) and whether they are local or imported. Solar panels on the other hand, are thrice the price of a wind turbine.

As far as maintenance is concerned, “The wind turbine is a moving part as is the propeller and the motor in it,” says Shahid. The motor needs to be oiled once a year, says Ali. And the battery needs attention too. If it is a wet battery, then the water level needs to be checked each month and distilled water needs to be filled in. In the case of a dry battery, once in three months. The propellers need to be cleaned occasionally to keep the dust off them, as is the case with solar panels.

A minimum of two lakh rupees are required for a wind turbine — with installation — and more for a hybrid system, as solar panels cost between Rs 300 and Rs 400 per watt. No combined package is offered for a hybrid system, and the turbines and panels have to be bought separately, but can be purchased from the same company, if they deal in both. Saif purchased his turbines on lease. “To get a lease for ours wasn’t easy to secure, since it was something new, but if the government were to encourage banks to lend and lease it would become far more feasible.” Mesec Group also provides turbines for wind farms and villages by the name of Pak Wind Energy, and thus they have a ready stock of 30kW equipment. Ali on the other hand caters to a niche market and imports pieces on demand.

Considering that the market is fairly new for alternative energy in Pakistan, especially the domestic sector, those looking into it as an option for their homes must do a lot of homework on their part and the companies providing these services. At the same time, they should also be prepared to make a risk-based investment. Several companies are cashing in on this steadily growing market, but not all are reliable. And then there are those like Shahid and Mabzi, who advocate the use of alternative energy and have installed a hybrid system in their own houses to lead by example and encourage others to do the same.