By Muhammad Soban ISLAMABAD, Feb 01 (INP-Wealthpk): Throughout economic development, mankind has been heavily dependent on different sources of energy over the centuries. In the 19th century, coal was the primary source of energy, while in the 20th century oil has become the primary energy source for economies to move on. Currently, the total population of the world is around 7.8 billion, increasing at a rate of 1.03 percent annually. The need for energy requirements has thus been growing globally over the years. Many countries are facing an energy crisis that is impacting on their economies. Pakistan is also one of the countries that have been facing the energy crisis over the last two decades. Its energy demand is growing 11 to 13 percent annually. Many conventional energy sources, including oil, gas, hydel, coal, and nuclear, are used to meet the energy requirement around the world, but these sources are depleting over the years. The demand is increasing but due to limited supply, the prices are rising in the international market. To fulfil the energy requirement, the world is moving towards renewable energy resources like the solar energy, wind energy, marine energy, and bioenergy. In bioenergy, biogas is one of the renewable sources of energy. Biogas is the gaseous product of anaerobic digestion. It is a biological process in which micro-organisms break down biodegradable material in the absence of oxygen. Biogas comprises methane (50 to 70 percent) and carbon dioxide (30 to 50 percent), with trace amounts of other particulates and contaminants. Biogas can be produced from various waste sources, including wastewater, animal manure, and industrial and commercial organic waste. It can also be produced from lignocellulosic biomass, including crops and forest residuals, dry fermentation, and thermochemical conversions. According to the World Biogas Association (WBA), humans generate 105 billion tonnes of organic waste every year. This organic waste releases harmful methane and other greenhouse gas emissions directly into the atmosphere during their decomposition. These organic wastes include food waste, sewage and garden waste, food and drink processing, and farm and agricultural waste. Currently, only 2% of this waste is treated and recycled. Furthermore, the WBA report suggests global Greenhouse Gas (GHG) emissions can be reduced to 10 percent by 2030 by simply managing these important bioresources more effectively. Estimates indicate that digesting 1 million tons of food waste would produce 115 million cubic meters of biomethane, equivalent to 650,000 barrels of oil. The concept of biogas is not new in Pakistan and can be traced back to the 1970s. More than 1,700 biogas plants were installed across the country through different programs of the Government of Pakistan in 1974. Lately, the Energy Development Board, Pakistan Centre for Renewable Energy Technologies, National Agricultural Research Council, Asian Development Bank, Pakistan Poverty Alleviation Fund (PPAF), Rural Support Programmes Network (RSPN), National Rural Support Programme (NRSP) and smaller NGOs also provided funds for installation of thousands of biogas plants across the country. The potential of biogas in Pakistan is very high. According to the International Renewable Energy Agency statistics, Pakistan’s energy production capacity from total renewable energy sources is 12,896MW. There are many indirect benefits associated with these renewable energy resources, especially biogas. It is a cheap energy source in far-flung areas where people cannot access natural gas for cooking. Biogas can provide them with an excellent alternative to fossil fuels. They can use biomethane gas for cooking and power generation. There are different types of biogas plants that can be installed to produce biogas at the small and large scale. Humans and animals produce different types of organic wastes, including crops residuals, animal manure, waste water, and food wastes. This waste decomposes and produces different gases that are causing climate change. Turning these wastes into biogas can be better used in generating electricity and heating, and as digestate [the material remaining after anaerobic digestion of a biodegradable feedstock].