Biogas
Biogas is a gaseous renewable energy source[1] produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste, wastewater, and food waste. Biogas is produced by anaerobic digestion with anaerobic organisms or methanogens inside an anaerobic digester, biodigester or a bioreactor.[2] The gas composition is primarily methane (CH
4) and carbon dioxide (CO
2) and may have small amounts of hydrogen sulfide (H
2S), moisture and siloxanes. The methane can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used in fuel cells and for heating purpose, such as in cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat.[3]
After removal of carbon dioxide and hydrogen sulfide it can be compressed in the same way as natural gas and used to power motor vehicles. In the United Kingdom, for example, biogas is estimated to have the potential to replace around 17% of vehicle fuel.[4] It qualifies for renewable energy subsidies in some parts of the world. Biogas can be cleaned and upgraded to natural gas standards, when it becomes bio-methane. Biogas is considered to be a renewable resource because its production-and-use cycle is continuous, and it generates no net carbon dioxide. From a carbon perspective, as much carbon dioxide is absorbed from the atmosphere in the growth of the primary bio-resource as is released, when the material is ultimately converted to energy.
The London Borough of Hackney (/ˈhækni/ ⓘ HAK-nee) is a London borough in Inner London, England. The historical and administrative heart of Hackney is Mare Street, which lies 5 miles (8 km) north-east of Charing Cross. The borough is named after Hackney, its principal district. Southern and eastern parts of the borough are popularly regarded as being part of east London that spans some of the traditional East End of London with the northwest belonging to north London. Its population is estimated to be 281,120.
The London Plan issued by the Greater London Authority assigns whole boroughs to sub-regions for statutory monitoring, engagement and resource allocation purposes. The most recent (2011) iteration of this plan assigns Hackney to the 'East' sub-region,[2] while the 2008 and 2004 versions assigned the borough to "North" and "East" sub-regions respectively. The modern borough was formed in 1965 by the merger of the Metropolitan Borough of Hackney with the much smaller Metropolitan Boroughs of Stoke Newington and Shoreditch.
Hackney is bounded by Islington to the west, Haringey to the north, Waltham Forest to the north-east, Newham to the east, Tower Hamlets to the south-east and the City of London to the south-west. Hackney was one of the host boroughs of the London Olympics in 2012, with several of the Queen Elizabeth Olympic Park venues falling within its boundaries.