International Conference on Mechanical, Industrial and Energy Engineering 2010 23-24 December, 2010, Khulna, BANGLADESH * Corresponding author. Tel.: +88-01912669030 E-mail address: tanzir68@gmail.com MIE10-110 Power System Integration and System Planning of MHD Power Plant S.M.Ferdous 1,* , Enaiyat Ghani Ovy 2 , Sayedus Salehin 2 , A. N. M. Mushfiqul Haque 1 , Md. Rezaul Hasan 1 , M. Shahed Hossain 3 1 Department of Electrical and Electronic Engineering, Islamic University of Technology, Gazipur-1704, BANGLADESH 2 Department of Mechanical and Chemical Engineering, Islamic University of Technology, Gazipur-1704, BANGLADESH 3 Department of Mechanical Engineering, Khulna University of Engineering & Technology, Khulna-9203, BANGLADESH ABSTRACT MHD power plants can be built as new stand-alone or combined cycle plants or an MHD plant can be added on i.e. retro fitted to an existing plant. A retrofit option is particularly attractive for older plants that have to be reconditioned since these may increase the generating capacity of the existing plants and at the same time, reduce the emission of pollutants and cooling water requirements. This would extend the life of an existing power plant and improve its environmental intrusion. This paper describes system planning and power system integration of a model MHD power plant. Many of the thermal power plants commissioned in Bangladesh are 30-40 years old. Retrofitted MHD power plants may be an option to increase the performance of these plants as there remains a large coal reserve in Bangladesh where the gas reserve is approaching towards its end. The feasibility studies of MHD plants demonstrated that combined cycles using both open and closed cycle MHD processes should be economically competitive. The technology has reached the stage where the feasibility of retrofit demonstration plant is considered by several countries including USA, Russia, China, Japan, India and Australia. A developing country like Bangladesh may step forward to adopt the technology to handle its recent energy crisis. Keywords: System Integration, Retrofitted MHD plants, Pollution control, Power conditioning, MHD-steam combined cycle. 1. Introduction The integration of MHD power plants, being a new technology, into electric utility service is a complex and tedious process as it would require a specific technology that would enable it to generate with the existing large interconnected utility networks with sufficient reliability. Studies have been showed that the efficiency of a combined cycle MHD steam power plant can be at least more than 20% about that offered by a conventional steam plant [1]. This should be possible at capital costs comparable with existing steam plants. Since the late 1950’s MHD has been under development as a candidate for control station generation using fossil fuels particularly coal [2]. The system schematic for a coal fired MHD plant is shown in fig.1 [3]. Two major limitations have been detected as prime constraint of MHD power plant integration to the utility. One is design and development of extremely high temperature sustainable system components (as MHD operates in a temperature range of 1500k-2500k). The other one is to determine the dynamic behavior of the plant when connected to the utility service (both transient and steady state stability) [3-4]. Due to its high operating temperature compared to any conventional power generating technology, MHD could still add up to 15 percent at the top end of other combined cycles. MHD is potentially a natural choice for conversion of high temperature energy output from future nuclear power plants. A combined nuclear-MHD system design with high efficiency has two major advantages [5]: • A reduction in thermal pollution • No CO 2 emission as with fossil fuel driven plants In most of the countries around the world including Bangladesh, solar and wind power has been introduced as a source of alternative energy, but only on a relatively small scale, since it is not yet economic. Oil fired plant is still widely used, but attempts are being made to replace it and this is where MHD could fit in. MHD is the only plant where coal can be used directly without pre cleaning. A system planning strategy needs to be developed to determine whether a MHD plant can be established to respond to power system requirements. A country like Bangladesh where energy crisis is one of the major rational concern, may step forward to consider MHD power plant as an option for power generation. With a large reserve of coal and replenishing reserve of gas combined cycle MHD/steam plant may be an answer to the problem. A retrofitting or repowering old station with MHD as a topping can significantly improve the efficiency. The older steam power plants commissioned in Bangladesh are operating way below the acceptable efficiency range. This may be improved substantially by retrofitting MHD plants with some modification at an acceptable economical expenditure. This paper is divided into seven sections. Section 1 and section 2 discusses the requirements and planning of the system. Section 3 and 4 focuses the comparative analysis of open cycle and closed cycle MHD plants. Finally section 5 and 6 discusses the process of retrofitting and MHD plant to any existing unit along with power conditioning. The conclusion part comments on the acceptability of MHD technology for Bangladesh.