For over 200 years the UK has relied on gas and currently supplies energy to around 85% of the population. As we move towards a greener, more sustainable future, there is an emerging focus towards more environmentally friendly gas – green gas. If we are to meet the climate change objective set through the Paris Agreement, which is to ensure global warming is kept well below 2C of pre-industrial levels, we must act now – else it will be too late. Green gas will help us make a positive step towards this critical goal.
Below are a number of green gas options, which in the future could be viable heating options for gas fires and other appliances in the home.
Biomethane – This is gas captured from anaerobic digestion. Essentially it is waste processing, which produces the gas for commercial use. Companies such as Severn Trent already use biomethane, which is injected into the grid. Energy companies such as Ecotricity are already supplying green gas through anaerobic digestion. Their green gas is produced from green gasmills, which have the following benefits:
Bio-SNG – SNG stands for Synthetic Natural Gas. This gas is produced from waste, which would have otherwise gone to landfill or incineration. This type of gas is being used with some HGV’s and it is quite feasible for such gas to be fed into the gas grid, once it has been blended to the required standard.
Hydrogen – There is current work underway to establish the potential for blending hydrogen, up to 20% into the normal gas supply, to reduce carbon dioxide (CO2). HyDeploy is looking at the level of hydrogen, which could easily be used by consumers who use gas, with no changes to their behaviour or gas appliance.
Challenges for hydrogen as heat:
Visibility – Natural gas burns with a blue flame under normal combustion. Hydrogen burns with a pale blue flame, which is not that easy to see in daylight – this has significant safety problems for obvious reasons.
Detection – Non toxic aroma such as mercaptan is added to natural gas so we can detect. However, this has a detrimental effect when using with hydrogen. There is current research taking place to look at addressing this issue.
Transportation – Compared to oil, which can be sent through pipelines, hydrogen transportation can be expensive. This is a set back since storage and transport can be considered impractical.