Renewable natural gas
Encyclopedia
Renewable natural gas, also known as sustainable natural gas, is a biogas
which has been upgraded to a quality similar to fossil
natural gas
. A biogas is a gas methane
obtained from biomass
. By upgrading the quality to that of natural gas, it becomes possible to distribute the gas to customers via the existing gas grid, and burned within existing appliances. Renewable natural gas is a subset of synthetic natural gas or substitute natural gas
(SNG).
Renewable natural gas can be produced economically, and distributed via the existing gas grid, making it an attractive means of supplying existing premises with renewable heat
and renewable gas energy, while requiring no extra capital outlay of the customer.
The existing gas network allows distribution of gas energy over vast distances at a minimal cost in energy. Existing networks would allow biogas to be sourced from remote markets that are rich in low-cost biomass (Russia or Scandinavia for example).
The UK National Grid believes that at least 15% of all gas consumed could be made from sewage slurry, old sandwiches and other food thrown away by supermarkets, as well as organic waste created by businesses such as breweries.
Renewable natural can be manufactured through three main processes; anaerobic digestion of organic (normally moist) material, thermal gasification
of organic (normally dry) material and produced through the Sabatier reaction
. In these cases the gas from primary production has to be upgraded in a secondary step to produce gas that is suitable for injection into the gas grid.
, Sweden
.
In the UK, the National Non-Food Crops Centre found that any UK BioSNG plant built by 2020 would be highly likely to use ‘clean woody feedstocks' and that there are several regions with good availability of that source .
is growing as a means of producing renewable biogas
, with nearly 50 sites built across the country. Ecotricity has announced plans to supply green gas to UK consumers via the national grid. Centrica has also announced that it will soon begin injecting gas, manufactured from sewage, into the gas grid. In Canada, FortisBC, a gas provider in British Columbia, has begun injecting limited amounts of renewably-created natural gas into its existing gas distribution system to begin to offer customers renewable gas options.
Sustainable Synthetic Natural Gas
Sustainable SNG is produced by high temperature Oxygen blown slagging co-gasification at 70 to 75 bar pressure of liquid and solid contaminated and wood, biomass, negative cost hazardous and non-hazardous wastes, coal and Natural Gas. This uses coal to SNG technology developed from the end of WW2 onwards, and successfully demonstrated at SVZ Schwarze Pumpe. The same technology can be transferred from the low grade lignite to fertiliser industry, where it is currently being successfully developed in China, to the renewable energy industry.
The advantage of a wide range of feedstocks is that much larger quantities of renewable SNG can be produced compared with Biogas, with fewer supply chain limitations. A wide range of fuels with an overall biogenic Carbon content of 50 to 55% is technically and financially viable. Hydrogen is added to the fuel mix during the gasification process, and Carbon Dioxide is removed by capture from the purge gas 'slip stream' Syngas clean-up and catalytic methanation stages.
Large scale Sustainable SNG will enable the UK gas and electricity grids to be substantially de-carbonised in parallel at source, while maintaining the existing operational and economic relationship between the gas and electricity grids. Carbon Capture and Sequestration can be added at little additional cost, thereby progressively achieving deeper de-carbonisation of the existing gas and electricity grids at low cost and operational risk. Cost benefit studies indicate that large scale 50% biogenic Carbon content Sustainable SNG can be injected into the high pressure gas transmission grid at a cost of around 65p/therm. At this cost, it is possible to re-process fossil Natural Gas, used as an energy input into the gasification process, into 5 to 10 times greater quantity of Sustainable SNG. Large scale Sustainable SNG, combined with continuing Natural Gas production from UK Continental Shelf and unconventional gas, will potentially enable the cost of UK peak electricity to be de-coupled from international oil denominated 'take or pay' gas supply contracts.
Biogas
Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
which has been upgraded to a quality similar to fossil
Fossil fuel
Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years...
natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
. A biogas is a gas methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
obtained from biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
. By upgrading the quality to that of natural gas, it becomes possible to distribute the gas to customers via the existing gas grid, and burned within existing appliances. Renewable natural gas is a subset of synthetic natural gas or substitute natural gas
Substitute natural gas
Substitute natural gas, or SNG, can be produced from fossil fuels such as lignite coal or from biofuels, when it is named Bio-SNG.In the Great Plains, USA, approximately 15 TWh/year of SNG from lignite coal is injected into the national gas grid...
(SNG).
Renewable natural gas can be produced economically, and distributed via the existing gas grid, making it an attractive means of supplying existing premises with renewable heat
Renewable heat
Renewable heat is an application of renewable energy and it refers to the renewable generation of heat, rather than electrical power ....
and renewable gas energy, while requiring no extra capital outlay of the customer.
The existing gas network allows distribution of gas energy over vast distances at a minimal cost in energy. Existing networks would allow biogas to be sourced from remote markets that are rich in low-cost biomass (Russia or Scandinavia for example).
The UK National Grid believes that at least 15% of all gas consumed could be made from sewage slurry, old sandwiches and other food thrown away by supermarkets, as well as organic waste created by businesses such as breweries.
Manufacturing
A biomass to SNG efficiency of 70% can be achieved. costs are minimized by maximising production scale, and by locating plant next to transport links (e.g. a port or river) for the chosen source of biomass. The existing gas storage infrastructure would allow the plant to continue to manufacture gas at the full utilisation rate even during periods of weak demand, helping minimise manufacturing capital costs per unit of gas produced.Renewable natural can be manufactured through three main processes; anaerobic digestion of organic (normally moist) material, thermal gasification
Gasification
Gasification is a process that converts organic or fossil based carbonaceous materials into carbon monoxide, hydrogen, carbon dioxide and methane. This is achieved by reacting the material at high temperatures , without combustion, with a controlled amount of oxygen and/or steam...
of organic (normally dry) material and produced through the Sabatier reaction
Sabatier reaction
The Sabatier reaction or Sabatier process involves the reaction of hydrogen with carbon dioxide at elevated temperatures and pressures in the presence of a nickel catalyst to produce methane and water. Optionally ruthenium on alumina makes a more efficient catalyst...
. In these cases the gas from primary production has to be upgraded in a secondary step to produce gas that is suitable for injection into the gas grid.
BioSNG
Göteborg Energi and E.ON are hoping to be among the first to develop a commercial scale BioSNG plant in GothenburgGothenburg
Gothenburg is the second-largest city in Sweden and the fifth-largest in the Nordic countries. Situated on the west coast of Sweden, the city proper has a population of 519,399, with 549,839 in the urban area and total of 937,015 inhabitants in the metropolitan area...
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
.
In the UK, the National Non-Food Crops Centre found that any UK BioSNG plant built by 2020 would be highly likely to use ‘clean woody feedstocks' and that there are several regions with good availability of that source .
Biogas
In the UK, using anaerobic digestionAnaerobic digestion
Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is used for industrial or domestic purposes to manage waste and/or to release energy....
is growing as a means of producing renewable biogas
Biogas
Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
, with nearly 50 sites built across the country. Ecotricity has announced plans to supply green gas to UK consumers via the national grid. Centrica has also announced that it will soon begin injecting gas, manufactured from sewage, into the gas grid. In Canada, FortisBC, a gas provider in British Columbia, has begun injecting limited amounts of renewably-created natural gas into its existing gas distribution system to begin to offer customers renewable gas options.
Sustainable Synthetic Natural Gas
Sustainable SNG is produced by high temperature Oxygen blown slagging co-gasification at 70 to 75 bar pressure of liquid and solid contaminated and wood, biomass, negative cost hazardous and non-hazardous wastes, coal and Natural Gas. This uses coal to SNG technology developed from the end of WW2 onwards, and successfully demonstrated at SVZ Schwarze Pumpe. The same technology can be transferred from the low grade lignite to fertiliser industry, where it is currently being successfully developed in China, to the renewable energy industry.
The advantage of a wide range of feedstocks is that much larger quantities of renewable SNG can be produced compared with Biogas, with fewer supply chain limitations. A wide range of fuels with an overall biogenic Carbon content of 50 to 55% is technically and financially viable. Hydrogen is added to the fuel mix during the gasification process, and Carbon Dioxide is removed by capture from the purge gas 'slip stream' Syngas clean-up and catalytic methanation stages.
Large scale Sustainable SNG will enable the UK gas and electricity grids to be substantially de-carbonised in parallel at source, while maintaining the existing operational and economic relationship between the gas and electricity grids. Carbon Capture and Sequestration can be added at little additional cost, thereby progressively achieving deeper de-carbonisation of the existing gas and electricity grids at low cost and operational risk. Cost benefit studies indicate that large scale 50% biogenic Carbon content Sustainable SNG can be injected into the high pressure gas transmission grid at a cost of around 65p/therm. At this cost, it is possible to re-process fossil Natural Gas, used as an energy input into the gasification process, into 5 to 10 times greater quantity of Sustainable SNG. Large scale Sustainable SNG, combined with continuing Natural Gas production from UK Continental Shelf and unconventional gas, will potentially enable the cost of UK peak electricity to be de-coupled from international oil denominated 'take or pay' gas supply contracts.
See also
- Anaerobic digestionAnaerobic digestionAnaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is used for industrial or domestic purposes to manage waste and/or to release energy....
- BiogasBiogasBiogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
- Biogas powerplant
- BiofuelBiofuelBiofuel is a type of fuel whose energy is derived from biological carbon fixation. Biofuels include fuels derived from biomass conversion, as well as solid biomass, liquid fuels and various biogases...
- Landfill gasLandfill gasLandfill gas is a complex mix of different gases created by the action of microorganisms within a landfill.-Production:Landfill gas production results from chemical reactions and microbes acting upon the waste as the putrescible materials begins to break down in the landfill...
- Landfill gas utilizationLandfill gas utilizationLandfill gas utilization is a process of gathering, processing, and treating the gas to produce electricity, heat, fuels, and various chemical compounds. The number of landfill gas projects, which convert the methane gas that is emitted from decomposing garbage into power, went from 399 in 2005 to...
- Renewable energyRenewable energyRenewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable . About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from...
- Renewable heatRenewable heatRenewable heat is an application of renewable energy and it refers to the renewable generation of heat, rather than electrical power ....
- Sustainable energySustainable energySustainable energy is the provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs. Sustainable energy sources include all renewable energy sources, such as hydroelectricity, solar energy, wind energy, wave power, geothermal...