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NETWORK / 23 / OCTOBER 2016 KEY POINTS • The Thames Valley area, to the west of London, takes in parts of Oxfordshire, Berkshire, Buckinghamshire, Hampshire and Surrey. • It has a diverse mix of industrial, commercial and small business development, along with a range of housing types with some areas of deprivation. • Activity is centred on Bracknell, where the project's lead local authority partner, Bracknell Forest Council, is newly committed to developing a lower carbon economy and is keen to promote the uptake of such technologies. • To date, there have been no signifi cant low-carbon initiatives, making the project's focus area the ideal blank canvas for the proposed trials. form of feeder level monitoring. This approach is generally con- sidered justi ed by the relatively high reliability of LV cables. The success of this philosophy has been supported by three key enablers. Power has exclusively • owed from the top of the LV network to the customer, DNOs understand the typical daily electricity usage patterns of various customer types. But, perhaps most crucially, DNOs have learnt to quantify the diversity of customer demand and how this typically reduces the peak demand from its theoretical maximum. This allows them to install e€ ciently sized cables and develop a more economic overall network design. If trends emerge that mean customers start using electricity in less diverse ways or even start exporting power to the network, then the success of the traditional LV network design begins to be undermined. Voltage deviation Customers who t solar panels to their homes, install electricity storage behind the meter or buy an electric vehicle don't need to gain consent from the network company beforehand. If this only happens at one or two households, this is unlikely to overload or cause serious voltage deviations on the local feeder. It's also less of a problem if the customer behaviour remains su€ ciently "diverse". But it is becoming clear that non-diverse devices, such as domestic solar, and large loads, such as electric vehicles, are being connected in volumes that may result in changes to traditional design assumptions. Real time visibility The NTVV project trialled a range of network monitoring techniques. The project demanded a rm understanding of electricity usage patterns of trial participants and information on the power • ow of LV feeders in the trial area. This justi ed the development of a LV network monitoring system, involving the tting of monitors in substations and at customers' properties. In addition to the bene ts provided by real-time visibility of LV networks, NTVV indicated that signi cant value was found in storing all of this information for later analysis because it would give network planning teams a more robust basis on which to forecast network • ows and usage, which will be key to e€ ciently planning and operating future LV networks. However, monitoring of the LV network created a lot of data. To leverage the full value of this data required a smart system to take it from the eld and to make it available to many diverse users. Within NTVV, the data was extensively presented in Scottish and Southern Electricity Networks' Distribution Management System (DMS) for operational users, and stored in Pi ProcessBook for accessibility by planning teams. NTVV also developed best practice for the selection of the monitoring and data management solution. A key learning was that there is unlikely to be a "one-size- ts-all" solution in the short term and installers may need to nd the "sweet spot" between maximum relevant data, accessibility and overall cost. Selection of future systems is likely to be driven by what is available as DNOs gain experience and learn what gives them best value. Cellular communications Traditional LV systems were never designed with the requirement for telemetry in mind. As a result, NTVV had to establish methodologies to allow measurement systems to be tted into legacy LV feeder pillars without the need for customer interruptions or compromising engineer safety. Monitoring equipment used during the trial provided half- hourly and real-time streamed data. The trials showed that streamed data may only be justi ed when used for the control of smart devices. In mainstream business-as-usual operation, all monitors tted should be able to stream data, but this would only be enabled where appropriate. NTVV focused on monitoring substations and users in the urban area in and around Bracknell. Because of the general prevalence of cellular networks in the area, the project was able to take advantage of the plug-and-play nature of data networks such as 2G and 3G. However, in some trial areas, access to GSM and UMTS cellular communications was found be more challenging. In these cases it was found that communication and connection rate can generally be improved by means of a • exible antenna mounting arrangement, allowing the antenna position London Bracknell