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flexibility in great britain’s gas networks

coincident; the increases and decreases FIGURE 2 LINEPACK OF NTS AND LOCAL GAS SYSTEM 2013-01-01 TO 2018-03-07
in linepack in the distinct parts of the
gas network happen at similar times.
A potential reason for this is the need
for flexibility in the NTS being driven
by CCGT power stations as well as
demand from the GDN, and the need for
flexibility in the GDN being driven by
space heating and hot water demand.
CCGT power stations typically ramp up
their gas demand in the heating season
from 5am-8am (to provide increases in
electricity demand), a similar time that
demand ramps up on the GDN for space
heating and hot water.
Secondly, even though there is five
to six times the amount of linepack
in the NTS in comparison to the GDN,
point, with a view to narrowing down
the amount of within-day linepack or at a household level could reduce http://www.ukerc.ac.uk/publications/linepack.html
flexibility (the useful operational the need for within-day flexibility potential options in the future.
storage) is typically higher in the GDN. if appropriately controlled; electric
Thirdly, the routine utilisation and vehicles are another technology that Conclusions
scale of within-day linepack flexibility has the potential to provide within-day The values for within-day linepack
points to the critical role of gas storage and reduce or support the wider flexibility that Britain’s GDNs currently
infrastructure in providing flexibility to system needs of flexibility. provide have not previously been
Britain’s current energy systems. Behaviour change and technology understood at a national level. This
choices such as full and hybrid heat research therefore provides additional
pumps also have potential to reduce evidence to help inform the planning
Potential implications the need for within-day flexibility by of Britain’s future energy systems. The
for research and innovation spreading energy demand further over future role of Britain’s gas networks in a
The analysis illustrates the scale of the the day. This would tend to smooth decarbonised energy system is subject
within-day flexibility currently afforded rather than concentrate demand, and to ongoing discussion and debate which
to Britain’s energy systems by virtue therefore lessen the need for within- this analysis seeks to inform through a
of having a gaseous energy vector day flexibility overall. Reducing overall greater understanding of the existing
contained in an extensive high-pressure demand is also highly likely to reduce energy system.
network of pipelines. the need for flexibility too, and is an There is a real risk that without
In comparison, the electricity grid has additional benefit from an increasing sufficient focus on managing and
no inherent means of storing electrical decoupling demand for space heating
energy within the delivery infrastructure and hot water in particular, when
itself (the electrical cables). Electric vehicles are another considering shifting demand off the
A gas grid that transports drop-in technology that has the potential gas system (e.g., onto the electricity
replacements for fossil natural gas to provide within-day storage system), that too much of the need for
such as bio-synthetic natural gas could within-day flexibility will be shifted
potentially continue to use linepack and and reduce or support the wider across too. The existing within-day
linepack flexibility in a similar manner system needs of flexibility flexibility provided by pumped storage
to today, even though overall gas is around 1/20th of the within-day GDN
demand is expected to decline. linepack flexibility alone.
However, a gas grid that transports focus on energy efficiency. Reducing the need for the existing
100 per cent hydrogen would Research to understand the range and levels of within-day linepack flexibility
require detailed network analyses to limits of potential alternative low-carbon in Britain is an energy system challenge
understand how much linepack that options should be a focus. How much that requires a substantially increased
new high-pressure pipelines could be can the need for energy system flexibility level of focus and effort in the near to
designed to hold, and the within-day be reduced by changing behaviours that medium term.
flexibility of hydrogen linepack. underlie the coincident demand for space The scale of the within-day flexibility
Reducing the need for within- heating and hot water? What are the currently provided by the natural gas
day flexibility is expected to be costs, benefits and limits to the reduction transmission and distribution networks
beneficial, regardless of the choice in flexibility afforded by measures such points to a formidable energy systems
of future primary energy supplies as better insulated homes, smarter challenge; how to provide low-carbon
and their associated networks that heating, time-of-use tariffs, flatter within-day flexibility to future energy
Britain implements to achieve a more demand profiles from heat-pumps, or systems at a reasonable cost.
ambitious net-zero target by 2050. This thermal energy storage in buildings on-
area should therefore be a target for site or at a larger scale? The UK Energy Research Centre carries
increased focus across the research and The scale of current within-day out world-class research into sustainable
innovation landscape. flexibility is so great, that it would seem future energy systems. For more
Increased deployment of thermal sensible to encourage several avenues information visit www.ukerc.ac.uk or
energy storage at a district heating of research and innovation at this tweet Dr Grant Wilson @DrIAGWilson

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