NON-CONVENTIONAL ENERGY SOURCES INCLUDE BIOMASS, HYDROPOWER, WIND POWER AND SOLAR POWER. NON-CONVENTIONAL ENERGY SOURCES THAT RELY ON WEAYTHER CANNOT BE COUNTED ON TO SUPPLY ENERGY AROUND THE CLOCK BECAUSE WIND SPEEDS COULD BE LOW OR THE WEATHER COULD BE CLOUDY FOR SEVERAL DAYS. SOME NON-CONVENTIONAL ENERGY SOURCES ARE LIMITED BASED ON GEOGRAPHIC FEATURES. HYDROPOWER CAN NOT WORK WHERE THERE IS NOW A DOWNHILL FLOW OF WATER AND WIND POWER WORKS BEST IN THE PLAINS BECAUSE OF THE HIGH WIND SPEED. NON-CONVENTIONAL ENERGY SOURCES EMIT LESS POLLUTION INTO THE AIR THAN FOSSIL FUELS, WHICH REDUCES GLOBAL WARMING AND ACID RAIN. THEY ARE ALSO RENEWABLE RESOURCES UNLIKE FOSSIL FUELS, WHICH WILL EVENTUALLY BE DEPLETED. THIS BOOK CONTAINS THE FUNDAMENTEAL AND BASIC INFORMATION OF SUBJECTS AND THE SELECTION OF CONTENTS MAKES IT AN APPROPRIATE  TEXTBOOK FOR THE STUDENTS.