Globally, Governments are seeking to lower greenhouse gas (GHG) emissions in the fight against climate change, to reduce waste to landfill, and to increase the use of renewable energy in compliance with international agreements. Consequently, in many countries, subsidies have been made available to encourage the growth of the biogas sector. According to the International Renewable Energy Agency (IRENA) a third of global power capacity is now based on renewable energy, and nearly two-thirds of all new power generation capacity added in 2018 was from renewables. Much of the recent growth was provided by solar and wind energy, but global…