In the utility sector, we’re all used to hearing about various innovations afoot in the electricity and water distribution sectors. Sensors, smart networks and demand response light up utility blogs and magazines. This is all good news, but amidst the hype of its noisier cousins, it’s easy to overlook the steady, diligent innovation of the gas distribution networks (GDNs).
GDNs have quietly set about implementing programmes to prepare for a tomorrow that demands both lower carbon emissions and protected prices. And though sensors and data will play a role, fundamentally it boils down to good old-fashioned engineering excellence. An excellent example of which is the gas pressure regulating valve.
Tomorrow’s gas pressure regulator
Pressure regulating stations (PRSs) are a core component of any gas distribution network, with thousands scattered around the country. PRSs typically perform reliably and effectively, with decades-old designs that have hardly been touched due to a laudable “if it ain’t broke, don’t fix it” philosophy.
However, despite robust performance and design, there is room for improvement over the standard PRS. Current set-ups rely on gas regulators with designs that have remained essentially unchanged for over a century. These designs incorporate a rubber diaphragm that is gradually corroded by the gas flow over time. Regular replacement of the diaphragm is key to ensuring continued reliable performance.
This can make operational expenditure (opex) on PRSs relatively high. It is an expensive thing to send a pair of engineers to often remote locations dotted around the country to maintain the PRS and replace the valve diaphragm. Doing it semi-regularly can become a major financial drain
Therefore, if a modern gas regulator design was capable of standing up to equally stringent safety and performance requirements while reducing maintenance costs, improving reliability and with similar or reduced initial capital expenditure (capex) outlays, it could be a major gamechanger for GDNs.
High reliability, lower whole-life costs
In the IM series gas regulator valve, that is what Oxford Flow has set out to provide. Featuring just a single moving part (reducing the likelihood for failure) and no rubber diaphragm to replace, the valve is capable of drastically reducing opex for comparable capex and performance.
This modern gas regulator valve is also known to have a superior response time to the traditional gas regulator, making it easier to install and set-up and less likely to cause network pressure spikes when doing so.
A hydrogen future
However, there are less incremental innovations that may also be in the pipeline for GDNs. With the threat of climate change and encroachment of legally binding targets on carbon emissions, policymakers are considering options for the decarbonisation of heat.
One of the frontrunner ideas is to gradually switch today’s existing natural gas network to carbon-free hydrogen. The idea holds appeal as much of the existing infrastructure and investment can continue to be used.
Of course, boilers and appliances in homes and business would require upgrading, and so would elements of the gas distribution infrastructure, including the PRS.
One issue is similar to today’s: frequent replacement of rubber diaphragms in gas regulators. However, as a much smaller particle, hydrogen may erode the rubber much more quickly than natural gas. Without the rubber seal, there is no fail-safe system and the network becomes unsafe. There remains research to be done into how much hydrogen will accelerate this process, both in a pure form and blended with natural gas. However, it is likely that a modern design without a rubber diaphragm will be an important component in a future hydrogen network.
Another potential issue for a hydrogen network – again requiring further research – is plantation. If hydrogen molecules are blended with natural gas and this causes aerobic reactions – or if small gaps allow some air in and cause the same – this can cause moss or plantation issues in the pipes and valves. If this is allowed to build up it could cause blockages and disruption to the end-user.
This is because current gas regulator designs involve a convoluted flow path, which allows debris to get stuck and accumulate. A modern gas regulator relies instead on an axial flow path, which could make it easier for debris to pass straight through and be caught in the GDN’s strainers downstream.
With early trials underway and talk of more in the early 2020s, such as Northern Gas Network (NGN) and Cadent’s Hydeploy2, the time is ripe for GDNs to consider the infrastructure implications of taking such a course. Indeed, they already are – for example, NGN’s H21 and Southern Gas Network’s (SGN) Hydrogen 100 projects are both broader initiatives to pave the way for a hydrogen future.
Is the timing right for the gas regulator revolution?
Innovation comes into play at many levels, from wholesale overhaul of the country’s approach to heat, to incremental improvements in daily asset operation that add up to major cost savings. There remain research and trials to be done at both levels, but it seems clear that an update on the centuries-old gas regulator has a significant enabling role to play on both fronts. The time is right for a quiet gas regulator revolution.
Paul Johnson, Operations Director at Oxford Flow, has over 25 years’ experience as a fluid flow specialist. He began his career as Flow Programme Manager and Laboratory Manager at the National Engineering Laboratory in Scotland, before moving to the National Physical Laboratory (NPL) where he worked as Research Programme and Business Manager. He later joined technology and management consultancy PA Consulting, where he worked as Innovation Lead for the Energy and Utilities Practice in London.