Tap and Switch

Some of the readers may have come across one or more of the words ‘water treatment plant’ (WTP), ‘sewage treatment plant’ (STP) and ‘effluent treatment plant’ (ETP). A brief description of these three is given below. All these processes deal with treatment of water so that the levels of certain substances in it are reduced to acceptable levels based on what the water will be used for after treatment. While water treatment mainly deals with processing the water so that it becomes fit for specific uses, both sewage treatment and effluent treatment are done on used water or ‘wastewater’ to remove the contaminants added to it due to use so that it is fit for being released into other water bodies. Directly releasing untreated wastewater into natural water bodies leads to situations such as  rivers foaming excessively and lakes catching fire . Water treatment plant Water treatment plants are used for treatment of ‘raw’ water before supplying it further for use by people. Water from...

It is known that there are a number of different types of power generating stations in use. This piece will discuss the effects of their behaviour on planning of power generation. Demand Curve To begin with, let us consider the demand curve. ‘Demand’ is the amount of power instantaneously required by a piece of equipment. The combined demand of all the equipment running at any given time, plus the losses involved in transporting electricity from the generating station to the end user, are to be matched by the power generation in the power plants. This matching is essential as power cannot be stored on such a large scale, and because it is necessary to operate the power plants and maintain the grid in a stable condition. The demand curve usually follows a pattern over a 24-hour period. The demand is never zero, it does not drop below some minimum non zero value. Think of the midnight-early morning period, when electricity usage is minimum – things such as fans and refrigerators...