UNIT VI lecture notes on quantity surveying.pptx

quanity surveyinh

1. UNIT 6 ENERGY AND ENVIRONMENTAL POLLUTION ENERGY SOURCES: Energy is defined as capacity to do work. It is required for formation of environment as well as for its existence. There are two types of energy sources: Conventional energy resources Non-Conventional energy resources

2. CONVENTIONAL ENERGY SOURCES Once used cannot be replaced easily. Examples: Fossil fuels (coal, natural gas, petroleum) Nuclear fuels (uranium, thorium) ADVANTAGES: Higher output in terms of power and energy Easy for transportation Can produce large energy at low costs. DISADVANTAGES: Availability is limited. They cause air pollution

3. NON-CONVENTIONAL SOURCES: Also called renewable energy resources. They are inexhaustible The sources are solar energy, wind energy, tidal energy, biomass energy. SOLAR ENERGY: It is the main source of energy for almost all the activities on earth. Solar energy is used in the form of: 1. Solar water heater for heating water. 2.Photovoltaic cell for generation of electricity.

4. WIND ENERGY: It makes use of wind mills which are erected at high altitudes to run with the help of air currents. The energy generated is used for generating electricity, pumping water for agricultural purpose for grinding food grains etc.

5. TIDAL ENERGY: It is the type of hydropower used to generate the energy. It makes use of fluctuations in the sea level during high and low tides. Its main drawback is high initial cost and variable output.

6. BIOGAS ENERGY: Biogas is the gaseous product released form anaerobic decomposition of different bio-wastes. In this process the organic waste are anaerobically fermented by micro-organisms. The gas produced contains 60% methane and 40% CO 2 .

7. Effects: The waste may contaminate ground water. The municipal dumping site cause fly nuisance, odour around the site. Water logged air is unsuitable for agriculture. Excess fertilizer and pesticides make land unfertile. Remedial measures: Use of proper irrigation methods to avoid water logging. Controlled use of pesticides and fertilizers. Apply Solid waste management at municipal solid waste dumping site. Use incineration technique for ho spital waste Deep burial of radioactive waste