IEEE Power & Energy Magazine - September/October 2017 - 35

250

200
Installed Capacity (GW)

meet the security of supply
criterion. This is reflected
in lower capacity and, consequently, in reduced investment cost in peaking
capacity units.
✔ ✔ Transmission capital expense (T CAPEX). This component represents the investment cost associated with
the reinforcement of key
GB transmission corridors.
Improved use of wind resources in the north of GB
enabled by ES capacity in
other parts of the country
makes it more e- conomical to
reinforce north-south trans--
mission capacity.
✔✔ Storage capital expense (S
CAPEX). This component
appears negative in total
net savings, as this is the
addi-t ional cost required to
build new ES assets; hence,
it is offset against gross system savings.

80.6

86.4
150

100

14.1
29.8

2.8
10.8

19.3
2.8
15.3

29.8

46.0

22.8

5.7

10.8

28.9

32.0

15.0
3.1
2030

21.6
2050

19.0

19.3

5.7

22.8

29.8

15.3

22.8

46.0

30.6

10.8

28.9

18.0

25.9

13.7
3.1
2030

21.6

15.0
3.1
2030

2050

32.0
21.6
2050

Optimally Reduced
Optimally Reduced
Nuclear
Wind
20 GW of New Storage

No New Storage
OCGT

CCGT

Storage

Hydro

Other RES

Biomass

Wind

Nuclear

CCS

figure 3. The generation capacity mix in 2030 and 2050 before and after adding
20 GW of ES.

Value of Storage in Achieving Carbon
Targets at a Lower Cost

30
20
Installed Capacity (GW)

ES can deliver carbon savings through improved operational
efficiency of conventional plants and enhanced use of low-carbon generation. As a direct consequence, the deployment of ES
may enable a given carbon reduction target to be achieved with
lower capacity of low-carbon generation, bringing corresponding savings in investment cost.
To demonstrate the magnitude of this impact, a set of studies was carried out given the carbon intensity target of 100 g/kWh
in 2030 and 25 g/kWh in 2050. The base case assumed no
new ES added to the system. As shown in Figure 3, this scenario is characterized by 61 GW of combined wind and PV
capacity and 32 GW of nuclear capacity in 2050.
Two additional sets of studies were then carried out with
20 GW of additional ES present in the system: 1) with optimally reduced nuclear and conventional capacity, while maintaining the 2030 and 2050 carbon targets, and 2) with reduced
wind capacity. In both cases, the 20 GW of new ES made it
possible to avoid building a significant amount of low-carbon
generation capacity, while still meeting the same carbon emission targets.
The changes in the generation mix enabled by additional
ES capacity are presented in Figure 4. In 2030, the new ES
eliminates the need to install 1.2 GW of nuclear or 2.9 GW
of wind capacity as part of the mix delivering a carbon
in---tensity of 100 g/kWh. In 2050, on the other hand, as much
september/october 2017

66.4

20.0

-1.2
-8.4

-14.0

-2.9
-8.4

-15.4

-10

-0.2
-5.8

-20

-20.0

-30
-40

2030
2050
Optimally Reduced
Nuclear
OCGT

CCGT

2030
2050
Optimally Reduced
Wind
Storage

Wind

Nuclear

figure 4. The changes in the generation capacity mix in
2030 and 2050, driven by deployment of 20 GW of ES.

as 14 GW of nuclear capacity could be removed from the
system if a sufficient volume of ES is installed. Similarly,
ES would reduce the need for 15 GW of offshore wind
-generation, while still meeting the carbon emission target
of 25 g/kWh.
ieee power & energy magazine

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - September/October 2017