Overview of Renewable Energy Sources

Article excerpt

The past decade has seen a worldwide revival in the interest in renewable energy technologies. The World Summit for Sustainable Development (WSSD) in Johannesburg attempted to set targets for renewable energy in the energy mix of the world. The importance of the resource as clean, abundant, and competitive fuel has now been established. However there continues to be some debate on what is renewable resource of energy. Regardless of what the renewable energy is, what is clear that all sources of energy, which may be renewable do not classify as renewable. Clearly large hydro and nuclear electricity, although renewable do not fall within the definition of renewable as we see renewable. Renewable energy sources include small hydel energy, solar energy, wind energy, biomass energy and geo-thermal energy, etc. New renewable energy sources are added to this list as time passes, the latest of the new renewable resource being the fuel cell.

Renewable energy in Pakistan can be best termed as experimental. Neither are the ambitious claims of some over enthusiasts correct nor are the claims of those implementing the projects verifiable. In the book, Energy Resources and Utilization in Pakistan, Pakistan's solar resource has been calculated as 800 million MW. Clearly, even if academically true, it is far from what can be called the potential that could be harvested, at least in the foreseeable future.

Pakistan's record in the field of renewable has been rather poor. Pakistan was amongst the first developing countries to have a full-blown photovoltaic program in the late 70's but what followed became a model in the world of solar as "what not to do in solar energy". Some interest resurfaced in the mid 90's when the lucrative tariff offered by the Private Power Board lured some adventures, even ENRON and Kennetec to sign MOU for solar and wind power generation but nothing materialized. As of date renewable technologies have not made any notable contribution to national energy supplies.

Regardless of their success in Pakistan, renewable energy sources continue to get greater acceptance throughout the world as clean, perpetual and carbon dioxide free energy. Although some argue that renewable energy is not really GHG-free if the energy utilized in the manufacture of systems for the harnessing of renewable energy is accounted for, which can be quite significant in some cases. Further more the disposal of consumable and non-consumable equipment and accessories continue to be an environment issue.

Internationally, the costs of many of these technologies have dropped and their efficiencies increased. Wind has made some extraordinary strides especially in the last seven years. The World Summit has clearly signaled for new concession, financial tools, assistance, and aggressive strategies for the promotion of these technologies in the coming years.

Pakistan has a large resource base for employing renewables for meeting its energy needs. Only 55 percent of the nation's population has access to electricity from the national grid. The remaining is using kerosene, cow dung, wood and other fuels for lighting, heating and cooking. Some of the excess or often suppressed demand, especially in lighting can be met through these resources.

For the purposes of GHG abatement, the best technologies for the Pakistan market are solar photovoltaic; mini, micro and small hydro power plants; solar (thermal) water heaters; biogas and wind power plants. Fuel cell has a lot of potential but it still has a long way to go before they can be considered ready technology for Pakistan.

The now defunct Directorate General New and Renewable Energy Resources (DGNRER) had established demonstration photovoltaic modules for 18 stations as shown in Table 1.1. No significant progress has been made since their installation.

Desalination plants in coastal regions have been established under the Ministry of Sciences and Technology. …