The vast energy storage capacity of Great Britain’s gas networks has been highlighted by the UK Energy Research Centre (UKERC) in a new report.
The findings are based on analysis of the hourly linepack volumes within gas transmission and distribution networks over a period of more than five years starting in 2013.
The research shows they were able to provide up to 690GWh of within-day storage by varying the amount of gas injected into higher pressure pipelines. The figure does not include any capacity from purpose-built storage facilities.
Although the daily storage capacity of distribution networks was slightly lower in absolute terms – 377 GWh compared to 427 GWh – they provided much on a proportional basis. For context, the maximum hourly linepack for the transmission network over the period (4.1TWh) was nearly five times the figure for distribution networks (834TWh).
UKERC says the findings have important implications for the decarbonisation of heat, noting that power grid has “no inherent means of storing electrical energy within the delivery infrastructure itself”.
“There is a real risk that without sufficient focus on managing and decoupling demand for space heating and hot water in particular, when considering shifting demand off the gas system (e.g. onto the electricity system), that too much of the need for within-day flexibility will be shifted across too,” the report explains.
“Reducing the need for the existing levels of within-day linepack flexibility in Britain is an energy system challenge that requires a substantially increased level of focus and effort in the near to medium term.
“The scale of the within-day flexibility currently provided by the natural gas transmission and distribution networks points to a formidable energy systems challenge; how to provide low-carbon within-day flexibility to future energy systems at a reasonable cost.”
Given its lower energy density compared to methane, the report also calls for detailed analysis of how the storage capacity of gas networks would be affected by conversion to hydrogen.