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Projects: Projects for Investigator
Reference Number	NIA_NGTO027
Title	SMART GEO GRID
Status	Completed
Energy Categories	Other Power and Storage Technologies(Electricity transmission and distribution) 20%; Other Cross-Cutting Technologies or Research(Environmental, social and economic impacts) 80%;
Research Types	Applied Research and Development 100%
Science and Technology Fields	PHYSICAL SCIENCES AND MATHEMATICS (Computer Science and Informatics) 10%; ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 30%; ENVIRONMENTAL SCIENCES (Earth Systems and Environmental Sciences) 60%;
UKERC Cross Cutting Characterisation	Not Cross-cutting 100%
Principal Investigator	Project Contact No email address given National Grid Electricity Transmission
Award Type	Network Innovation Allowance
Funding Source	Ofgem
Start Date	01 September 2018
End Date	01 December 2018
Duration	ENA months
Total Grant Value	£55,095
Industrial Sectors	Power
Region	London
Programme	Network Innovation Allowance
Investigators	Principal Investigator	Project Contact , National Grid Electricity Transmission (100.000%)
	Industrial Collaborator	Project Contact , National Grid plc (0.000%)
Web Site	https://smarter.energynetworks.org/projects/NIA_NGTO027
Objectives	A novel approach is proposed to account for the uncertainty in predicting the behaviour of soils and their consequential impact on the safe functioning of key assets. At the heart of the proposed approach is the idea of integrating autonomous data logging with data input from modelling and GIS-based informatics to enable decisions to be made to improve safety and preserve the lifespan of assets. This approach was envisaged from the recognition that, while modelling is highly important in predicting future trends, it is limited by uncertainties associated with site-specific conditions. On the other hand, data acquisition from site provides an invaluable insight into the local conditions of the relevant soil mass, but when used in isolation requires potentially erroneous extrapolation to predict future trends. Combining the two offers a highly effective approach to allow for mitigating action to be taken before a critical condition is reached. This project will cover the following work packages:WP 1: Modelling through numerical simulationsTypically, thermal dissipation calculations are carried out in which the thermal resistivity is prescribed as a constant value, chosen by the user. Different scenarios are then considered; for example, analyses are carried out using representative values of thermal resistivity corresponding to “dry” and “wet” soils. It is proposed to carry out a more fundamental analysis, in which thermal resistivity is not prescribed as an “input value” but rather is considered a function of parameters defining the underlying soils behaviour (in particular, the porosity of the soil and the degree of saturation, which itself is permitted to vary with time). WP 2: Experimental investigationAt the heart of SMART GEO GRID is the idea that simulations alone are not sufficient since any simulation is only as good as the chosen values for the material/constitutive parameters (as well as the initial and boundary conditions). Instead, future predictions must be made conditional upon the measurements recorded at site through sensor acquisition. Only then can trust truly be placed in the simulation results and sufficient confidence gained with regard to the option to de-rate. It is proposed that a laboratory based set-up consisting of apparatus in which a short (i.e. “plane strain”) section of cable is mounted in a soil, which is to be instrumented with temperature and water content sensors. Heating elements mounted inside the section of cable will simulate the heating induced by the flow of electricity. The subsequent water content variation and temperature profiles throughout the soil mass will be measured with the intention of providing a set of data, experimentally obtained, against which the simulation results can be “trained” to provide accurate predictions.WP 3: Parameter estimation: combining the experimental investigation and simulation resultsThe key aspect of our proposal is the uniting of numerical simulations and data acquisition. The third work package considers this important aspect, specifically addressing the question: how should the simulations be adjusted in light of the measurements to facilitate accurate future predictions? This work package will principally involve software development, using algorithms to “train” the simulations in response to the acquired data. Initially, the study will just focus on material parameter tuning, aiming to develop robust software that can adjust the appropriate material and constitutive parameters in a fully automated way to allow for faithful future predictions. Software will be developed using synthetic training data initially (i.e. data generated from numerical simulations) before attempting to apply it to the results of our laboratory experimental testing programme.WP 4: Costing and practicality reportA desk study to investigate all of the practical aspects of deploying this sensor acquisition approach proposed in this project will be undertaken; allowing the full costs of the system to be understood. The project has the following objectives: Develop numerical models of the soil condition and link this to the thermal loading of underground cables. Validate the models with experimental results from an equivalent laboratory setup. Train software to provide predictions of the soil condition; allowing a forecast to be made. Develop a costed proposal for deploying this technology in the GB network.
Abstract	The material surrounding buried electrical cable is required to dissipate heat at a sufficiently high rate to prevent thermal overloading. In design, conservatism can be applied to attempt to prevent critical situations from arising. For example, the cable spacing can be chosen with an appropriate factor of safety. However, soils are highly complex materials, possessing material properties that are not constant but rather vary temporally and spatially, sometimes by several orders of magnitude. Envisaging and accounting for all eventualities is a highly challenging and potentially costly task. As an example, both the thermal and electrical resistivities of soils are highly dependent on water content; in the event that a soil mass dries out, both its thermal and electrical resistivities will rise considerably, limiting its capability to dissipate heat and electricity.This project has the following objectives: Develop numerical models of the soil condition and link this to the thermal loading of underground cables. Validate the models with experimental results from an equivalent laboratory setup. Train software to provide predictions of the soil condition; allowing a forecast to be made. Develop a costed proposal for deploying this technology in the GB network.
Publications	(none)
Final Report	(none)
Added to Database	02/12/22