Line Rating
To keep up with increasing low-carbon generation and changes in consumer demand patterns, the capacity of existing electricity transmission networks has to be increased. This is expensive, so any way to avoid upgrading the lines, while still increasing the system’s capacity must be explored.
ReadOne way to increase the system’s ability to transmit electricity, whilst avoiding upgrading costs, is to the raise the static line rating (the amount of electricity that can be transmitted down the line without the conductors exceeding their designated operating temperature) of certain parts of the network.
The temperature of the conductors is affected by various factors. For instance, it’s raised by electric current passing through them, high ambient temperatures and solar radiation, and lowered by the cooling effect of wind and low ambient temperatures.
Of these factors, ambient temperature, solar radiation, wind speed and wind direction are weather related, but lots of electricity companies use the same static line ratings in areas that experience very different weather patterns.
These weather effects are currently only accounted for at a national level. Therefore, it’s exceedingly likely the static line rating for some transmission routes are overly conservative and can be increased by taking into account local weather.
This project is looking at how the weather affects the static line rating for each span in every route in the transmission network of the UK’s National Grid, helping them to identify routes that can safely have their static line ratings increased.
Substation Maintenance
In order to ensure faults are always kept to a minimum, electricity substations must undergo maintenance, including the cleaning and re-greasing of multiple components.
ReadThe maintenance windows currently in force on the almost 500 National Grid owned and operated electrical substations in England and Wales are based on the assumed local environment of each one. The variables that impact that environment include the level of airborne pollutants and any factors that could lead to corrosion.
The levels of these variables are currently assumed based on data that’s out of date. For example, levels of SO2 – a key driver for corrosion – have dropped dramatically over the past 20 years.
Using out-of-date data can lead to sub-optimal maintenance scheduling. This means certain low-risk substations are being over-maintained, resulting in unnecessary expenditure, while high-risk sub stations are being under-maintained, potentially causing faults.
This project will use the latest data to re-evaluate the levels of airborne pollutants and factors that lead to corrosion. Each substation will then be given a “maintenance risk score”. Current maintenance schedules will then be checked against this new data, and any substations whose maintenance schedule is at odds with their new “maintenance risk score” will be highlighted.
This will give the National Grid the most accurate data with which to make decisions regarding substation maintenance.
Renewable Analysis
As the volume of renewable generation added to electricity transmission and distribution networks increases, managing these systems has become much harder.
ReadFor example, in the UK a lot of the wind farms are in Scotland, but most of the usage is in London. So, the transmission network has to work really hard to move and electrify all that way.
Solar forecast is another illustration of this. If last-minute cloud cover comes over, conventional generators have to be fired up at great expense.
We are working on a model that simulates scenarios like these, which will allow transmission and distribution companies to understand the risks renewables present, plan better renewables deployment strategies, and forecast and react to problem areas, giving them more time to reinforce their network if needed.
Flood Risk
Electricity companies have lots of high value assets out in the field. Due to the sheer number of them, some will unfortunately be at very real risk of flooding.
ReadWhile the flood defences currently in place may be effective in some cases, they are implemented on the basis of data that might be out of date, which leads to some sites being needlessly overprotected, while some are chronically under protected. All of which means that investment in flood defences could be done better.
By re-evaluating all the latest flood risk data, we can better assess the current flood defence strategies of our clients, giving them the optimum data with which to make important decisions.