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R esearch by Barclays Bank recently estimated that the UK's power infrastructure needs an investment of £215 billion by 2030. The investment is required to satisfy a number of critical requirements. The needs include the replacement of aging assets, deployment to new industrial, residential and transport developments, and, most significantly, support for the transition from a centralised generating model towards a distributed model – in other words, a smart grid. Significant research has been conducted in the UK and globally into the electrical plant requirements necessary for the dynamic behaviour of equipment such as transformers, switchgear, power electronics and large-scale storage systems. Although there is still some way to go to perfect these advances, clear progress is being made. With the help of the Low Carbon Networks Fund (LCNF) initiative, some excellent proof of concept projects have been undertaken in the UK in areas such as dynamic thermal plant rating, grid storage, voltage control, electric vehicle charging points, network balancing, and so on. However, one area yet to receive sufficient attention is the communications technology needed for all the additional devices which will be required by a smart grid. At many innovation project presentations, the communications element of the scheme is glossed over or represented by a fluffy cloud of some description. Large innovation projects, run in a highly professional manner from the electrical perspective, appear to rely on a communications solution which is usually somewhat Heath Robinson, being neither reliable nor secure enough to be considered for mass deployment. Although smart grid communications requirements are still being defined (and even the meaning of 'smart grid' is still being debated), there are some indicators already of what will be required. Compared with the number of remotely addressable devices in today's electricity NETWORK / 36 / NOVEMBER 2016 utilising some services from public telecoms operators coupled with self-provide systems (especially pilot cable and VHF/UHF radio systems) usually supported by niche equipment vendors. This approach has worked well for decades, and successive upgrades to the technology have allowed the controlled use of an increasing number of secondary substations to facilitate the functioning of the highly reliable electricity network that we have today. However, a huge change is now looming. Smart grid comms standardisation There is perhaps an assumption by electrical design engineers that a telecoms solution will present itself from some as yet unknown source, either through a self-provided con- nection via a small internal telecoms team, or by placing an order with an external tel- ecoms operator. Unfortunately, neither of these options is currently available for rapid deployment or satisfies the relevant techni- cal criteria. The enormous increase in the number of devices and the data throughput required in the future will necessitate an increase of something like two orders of magnitude over the capability of the current supporting telecoms infrastructure. This capability cannot be built using the limited internal telecoms resources of most UK power companies. The electricity industry will have to bring in external resource to design and implement the upgrades required for the telecoms infrastructure to support smart grids. Typically, DNOs' telecoms teams are fully occupied in managing the move away from legacy time-division multiplexing (TDM) and plesiochronous digital hierarchy (PDH) telecoms services – which are rapidly becoming obsolete – to IP and ethernet alternatives. This migration is in itself an enormous undertaking. The same teams are also managing a large number of new connections to wind and solar installations using telecoms technology which is very limited in its expansion capability. In short, SMART GRID TELECOMS networks, the number of devices requiring connection is expected to have to increase 100-fold to support smart grid applications. Additionally, data rates to each of these devices will need to increase by 10-100 times compared with current throughputs of, typically, 300-1200bps at 11kV level. The duty cycle of many of these systems is also very low. There are also some specific requirements to be considered regarding the suitability of communications systems in the utility sector. While these are well known to those within the electricity industry, that is not necessarily the case for those outside it. Those specific requirements include: • Very high levels of security (in line with critical national infrastructure guidelines). • Availability of service throughout urban, rural, extreme rural and sub-surface locations. • High degree of power autonomy of telecoms services (including black start criteria at many locations). • Backwards compatibility with legacy equipment – oŸen proprietary serial interfaces developed by individual distribution network operators (DNOs) and now defunct equipment vendors. • Requirement for long-term future support (for decades) of systems. • The incremental cost of adding extra devices. Historically, the specific needs of these types of communications systems have been satisfied through a mixture of arrangements "Large innovation projects, run in a highly professional manner from the electrical perspective, appear to rely on a communications solution which is usually somewhat Heath Robinson."