Solar power station project inches forward

MBONGENI MGUNI
Staff Writer | Friday July 23, 2010 00:00

 

The feasibility study is expected to be complete in 12 months, paving way for project capitalisation by the BPC and its funding partners, construction and eventual commissioning.

The multi-million Pula project has its genesis in a 2006 renewable energy-based rural electrification agreement between the Government of Botswana and the United Nations Development Programme (UNDP). The solar power station is part of a range of initiatives to reduce the country's dependence on fossil fuel and costly diesel-fired power stations.

Last year, consultants to the BPC finalised a Pre-Feasibility Study (PFS) indicating that Botswana has good solar irradiation, capable of supporting a solar power station. The study also identified Jwaneng, Selebi-Phikwe, Serowe, Letlhakeng and Maun as ideal sites for the construction of such a station.

The study also proposed that the station take the form of 4 x 50 megawatt units, with the possibility of Independent Power Producer (IPP) involvement.

This week, the BPC kicked off a headhunt for feasibility study consultants towards the proposed solar power station. According to the BPC's tender documents, funding for the study has been sourced from the World Bank and the African Development Bank, who are also financing the P11 billion Morupule B Power Station and associated transmission works.

The power utility confirmed the PFS' indications for possible solar sites in Botswana.

'The outcome of the study confirms that indeed Botswana is receiving enough solar irradiation that can be harnessed to generate electricity through concentrating solar power technology.

'Five suitable sites have been identified and parabolic troughs were the recommended concentrating solar thermal power technology, among others,' the documents read.

Parabolic troughs, a widely used type of solar thermal energy collectors, are favoured in large solar power stations worldwide as they offer the lowest cost in the range of collector technology available. Parabolic trough technology is used in the more than 80 percent of the world's solar power stations, including those within, above and beyond the 200 MW range.

The consultants being sought by the BPC will be required to provide various technical and financial solutions to the proposed solar power station.These include performing a detailed financial and economic analysis, consisting of the calculation of electricity generation costs and a 'sensitivity analysis' on the electricity costs in relation to capital and operational expenditure, solar irradiation variance and plant degradation. 'The scope of work will also include identification of project risks and coming up with appropriate mitigating measures as well as performing a detailed assessment of plant location and design from the pre-selected areas referred to in the PFS,' tender documents read.

The feasibility study consultant will also be required to provide details on various technical components of the solar power plant such as solar fields, instrumentation and control, power block steam cycles and potential supplementary firing. Once the feasibility study is complete, BPC is expected to engage financiers like the World Bank and African Development Bank (ADB), for capital expenditure, enabling the development of Botswana's pioneering solar power station. Once completed, the power station will eclipse Morupule Power Station's current capacity, alleviate the prevailing power shortfall and diversify the country's power supply sources. It is expected that the power station will be used to supply the country's booming mining sector.

Globally, solar power stations are concentrated in the United States and Europe, with the largest of these being the 354 MW station in the Mojave Desert in California, United States of America (USA).