2014 Electricity Grid
This section provides a brief description of the UK electricity grid mix in 2014. It will provide a top level overview of the separate sectors which made up the supply grid in 2014, specifically the total installed capacities and generated output of the different energy sectors.
It should be noted that data regarding 2016 and 2015 has not been fully published nor is available, hence instead the 2014 grid is assessed because there are full and finalised publications available from the Department of Energy and Climate Change (DECC) and the National Grid.
It should be noted that data regarding 2016 and 2015 has not been fully published nor is available, hence instead the 2014 grid is assessed because there are full and finalised publications available from the Department of Energy and Climate Change (DECC) and the National Grid.
2014 Demand
In 2014, the total electrical energy demand for the UK was 302 TWh (Gridwatch & DECC, 2015) for the year. The demand fluctuates depending on the time of day, where it peaks during the working day and is at its lowest during the evening. There are also seasonal variations associated with the demand. During the winter season the overall demand is generally greater than during the summer season due to the increased heating demands. Figure 1 shows the fluctuations in demand throughout the year. Here we can observe that the demand is higher in the winter months and comparatively lower in the summer months.
Figure 2 shows demand variation during a typical winter week. Here too we can observe that an increase in heating causes an increase in demand at night compared to daytime. The week duration chart is shown in order to allow a clearer assessment of hourly changes throughout the day.
Figure 2 shows demand variation during a typical winter week. Here too we can observe that an increase in heating causes an increase in demand at night compared to daytime. The week duration chart is shown in order to allow a clearer assessment of hourly changes throughout the day.
2014 UK Installed Capacities
In order to meet the demand, the UK grid has a large network of a variety of energy systems. This section provides a breakdown of the different generation systems installed. These installed capacity data are obtained from DUKES (chapter 5.6 and 6.4) as shown in Figure 3.
In the UK, the total installed capacity is 85 GW, from which the major installed capacity share corresponds to that of the conventional power plants. Within the conventional power plants, Coal Fired has an installed capacity of 20 GW, which is 23.4% of the total and Combined Cycle Gas Turbines has an installed capacity of 34 GW, which is 39.8% of the total. These are the highest installed capacities, and are the key generation sources up to now as shown in Figure 5. Following the conventional power plants, the next big share belongs to Nuclear with an installed capacity of 10 GW and 11.7% of the total. Renewable installed capacity enclose a total of 25 GW, out of which wind takes the biggest share of total installed capacities. Low carbon technologies (Renewable technologies and Nuclear power combined) sum up a total of 35 GW of installed capacity which is almost equal to the installed capacity of Combined Cycle Gas Turbines.
In the UK, the total installed capacity is 85 GW, from which the major installed capacity share corresponds to that of the conventional power plants. Within the conventional power plants, Coal Fired has an installed capacity of 20 GW, which is 23.4% of the total and Combined Cycle Gas Turbines has an installed capacity of 34 GW, which is 39.8% of the total. These are the highest installed capacities, and are the key generation sources up to now as shown in Figure 5. Following the conventional power plants, the next big share belongs to Nuclear with an installed capacity of 10 GW and 11.7% of the total. Renewable installed capacity enclose a total of 25 GW, out of which wind takes the biggest share of total installed capacities. Low carbon technologies (Renewable technologies and Nuclear power combined) sum up a total of 35 GW of installed capacity which is almost equal to the installed capacity of Combined Cycle Gas Turbines.
Electrical Energy Generated
Figure 4 shows the generated electricity supplied by each sector in 2014. It is clear that in that year, UK was heavily reliant on conventional power plants (PP) that had a combined supply of approximately 63% of the total generation. Followed by this was Nuclear, which had an overall supply of 19%. The total supply of renewable energy systems was also 19%, out of which wind was the largest renewable energy contributor at approximately 10%.
Trends
From figure 6, it can be seen how coal, which was the major source of electricity generation in the 1980's and 1990's, declined steadily to approximately 30% in 2014. Gas, which had a rapid expansion in the early 1990's thereby becoming a major player for the last 2 decades, declined rapidly from 2010's to 30%. The growth of Nuclear was steady and controlled, from approximately 15% in the 1980 to about 19% in 2014, although there were some irregularities in the 1990's and 2000's. Oil, which started out at around 5-7% in the 1980, declined even further to less than 3% in the 2014, although a small rise can be seen in the first half of 1990's. Conventional Hydro which, which was the only renewable energy system in 1980, has been steady for the last 3 decades at approximately 3-4%. Other major renewable energy systems such as Wind and Solar started in the early 2000's but expanded rapidly due to many new government policies to approximately 14% in 2014. Also, the growth of the electricity imports has been steady from the second half of 1980's to 2014 at approximately 6%. It is noticed that there is a sudden decrease in generation and imports at 2008, due to the financial crisis.
2014 Storage Capacity |
European Link |
The total storage capacity of the electricity grid is around 30 GWh and is in the form of pumped storage. Pumped storage systems has turbines just like the ones in hydroelectric power plants, and use electricity, when it cheap (at times of low demand) to push water from a water source to an uphill reservoir, then reverse to flow to regenerate electricity when there is an increase in demand and the electricity is more valuable, thus a profit can be made.
The UK currently has 4 pumped storage facilities. Dinorwig in Wales, is the biggest with the energy storage of 9.1 GWh and a storage capacity of 1.8 GW. This capacity will have to increase in order to allow for increased penetration of renewable energy generation systems. |
The UK transmission system is linked via inter-connectors to the transmission systems in France, Netherlands and Ireland. The reason for this exchange is to allow for export at time of surplus power generation and import at times of excess demand and generation shortfall.
According to DUKES Chapter 5 (DECC, 2015), the UK was a net importer in 2014. UK imported 15 TWh from France and 7.9 TWh from Netherlands which in total makes up 6% of UK's electricity supply. Also, UK exported 2.4 TWh of electricity to Ireland. |
References
Department of Energy and Climate Change (DECC), 2015. Electricity: Chapter 5, Digest of United Kingdom Energy Statistics (DUKES).
Department of Energy and Climate Change (DECC), 2015. Renewable sources of energy: Chapter 6, Digest of United Kingdom Energy Statistics (DUKES).
Gridwatch, 2016. GB National Grid Status.
National Grid, 2016. Data Explorer.
Department of Energy and Climate Change (DECC), 2015. Electricity: Chapter 5, Digest of United Kingdom Energy Statistics (DUKES).
Department of Energy and Climate Change (DECC), 2015. Renewable sources of energy: Chapter 6, Digest of United Kingdom Energy Statistics (DUKES).
Gridwatch, 2016. GB National Grid Status.
National Grid, 2016. Data Explorer.