8. SYSTEM INTEGRATION OF VARIABLE RENEWABLE ENERGY

Advanced flexibility resources may include those provided by solar, wind and demand response, including from electric vehicles (EVs), battery storage, hydrogen and sector coupling.

India’s complex power system structure, power markets and regulations require a vision for the system as a whole and milestones for a reform roadmap. The Government of India (GoI) aims to create a 2030 vision for power market reform and an optimal power mix, bringing together the central government, states, regulators and market participants. The existing Central Energy Regulatory Commission (CERC) proposals form a strong basis, but will require an extensive stakeholder engagement process for implementation, notably at state level.

Supply and demand trends

India has seen a rapid increase in electricity generation from variable renewable energy (VRE) in recent years (Figure 8.1). Wind power capacity started to increase in the early 2000s and has grown at an annual average rate of 17% in the last decade, according to IEA data. Generation from solar power has only recently started to grow. In the five years 2012-16, solar power production increased by 44% on average every year.

Figure 8.1 VRE electricity generation by source and by share of total generation, 2001-17

Wind and solar power generation have increased rapidly in recent years, together accounting for 5% of total electricity generation in 2017 and continue to grow towards India’s 2022 target.

Source: IEA (2019a), World Energy Balances 2019, www.iea.org/statistics/.

In 2017 wind and solar power together accounted for 5% of total electricity generation. Compared to IEA member countries, this was at the low end of variable renewables in power generation (Figure 8.2). However, the share continues to increase as India pursues its ambitious targets for 100 GW of installed solar power and 60 GW of installed wind power by 2022.

8. SYSTEM INTEGRATION OF VARIABLE RENEWABLE ENERGY

from generation to transmission and distribution. Integrating VRE, particularly at higher shares, in a reliable and cost-effective manner requires different approaches compared to traditional power system planning and operation.

The IEA has developed a phased categorisation to capture the evolving impacts that VRE may have on power systems, as well as related integration issues. It categorises the integration of VRE into six different phases (see IEA and 21CPP [2018] for further details). This framework can be used to prioritise different measures to support system flexibility, identify relevant challenges and implement appropriate measures to support the system integration of VRE.

These phases also provide an assessment framework to understand current and future trends in system integration of renewables in India. Challenges depend on different phases of VRE deployment.1

Figure 8.4 Key characteristics and challenges in the different phases of system integration of VRE

8. SYSTEM INTEGRATION OF VARIABLE RENEWABLE ENERGY

These VRE-rich states (Figure 8.6) together accounted for 96% of VRE capacity deployment and 97% of total VRE generation in the country. Figure 8.6 shows installed VRE capacity as a percentage of total electricity capacity in each state (x-axis), VRE generation as a percentage of total electricity generation in each state (y-axis) and the phases of system integration. Table 8.1 highlights VRE capacity and generation data in renewables-rich states. Based on this analysis:

six of the high VRE states are in Phase 3 (Tamil Nadu, Gujarat, Andhra Pradesh, Karnataka, Rajasthan and Telangana).

three are in Phase 2 (Maharashtra, Madhya Pradesh and Punjab).

all other states, including Kerala, are in Phase 1.

Figure 8.6 VRE share of installed capacity and annual generation, top 10 VRE generating states grouped by system integration phase, 2018

Note: The size of the bubble corresponds to the total electricity generated in the state.

Sources: CEA (2019a), Renewable Energy Generation Report, March 2019, http://cea.nic.in/reports.html (actual VRE electricity generation from April 2018-March 2019); MNRE (2019), Total Installed Capacity, https://mnre.gov.in/physical-progress-achievements (VRE installed capacity as of 31 March 2019).

The six states in Phase 3 (Tamil Nadu, Gujarat, Andhra Pradesh, Telangana, Karnataka and Rajasthan) are responsible for 78% of total VRE generation of India. They have a high VRE deployment as a share of total capacity (between 20% and 40%), but show relatively low VRE generation as a share of the total (between 10% and 25%). This is due to the low capacity factors of wind and solar compared to thermal generation, but it is also an indicator of curtailment of renewables due to power system flexibility problems, including frequency, voltage and inertia issues, as well as transmission bottlenecks.

In Phases 1 and 2, VRE has a minor to moderate impact on system operation; however, the importance of power system flexibility will increase significantly in Maharashtra, Madhya Pradesh and Punjab in the coming years as they transit into Phase 3.