Energy consumption is a key factor in measuring the economic growth of a city/country. Even after 2015, fossil fuels are supplying the major part of energy demanded by people from all over the world. Air pollution, water pollution, biodiversity loss, deforestation, and global warming due to carbon emissions and climate change are some of the negative aspects of consuming fossil fuels for meeting the energy demand. So, it is high time to generate renewable energy, also known as green energy. Green energy is defined as the energy generated from the renewable sources such as sunlight, wind, biomass, and geothermal energy. For household/commercial purpose, the most critical issue is the effective reduction in the cost of electricity. For saving energy in buildings, vehicles, communication networks, and industries/factories, it is important to develop an energy monitoring/management systems. Like energy production, energy saving is also equally important because the amount of energy saved can be considered as the amount of energy generated. Therefore, it is extremely important to save energy as much as possible in consumer/industrial applications.