Wind-solar hybrid (WSH) power, which harnesses both solar and wind energy, is fast emerging as a viable new renewable energy (RE) option in India.
The way it works, generation of solar energy tends to peak during the day and that of wind energy at night. The resulting intermittencies in supply impact grid resilience, which makes distribution companies (discoms) reluctant to buy power from standalone wind and solar projects.
In the hybrid option, however, these two energy sources complement each other, which could help overcome the problems of variability of generation and grid security, and thereby discoms’ reluctance.
According to CRISIL Research estimates, 15 GW of WSH power will come up over the next five years, riding on strong support from central public sector undertaking Solar Energy Corporation of India and several state governments.
Of this, 10 GW is already in the works – either under construction or being tendered – and will start feeding the grid by fiscal 2024.
To put things in perspective, the country had 37.69 GW of standalone wind energy capacity and 35 GW of solar capacity as of fiscal 2020.
Says Rahul Prithiani, Director, CRISIL Research, “We expect the WSH market to grow and evolve as the number of projects and developers who seek to unlock value from the hybrid increases. However, the availability of good sites with strong irradiation and high wind speeds would be a key challenge, as evident in waning developer interest in the wind energy sector.”
According to CRISIL Research, there are proposals to set up 3.9 GW of pure-play WSH projects and 4.5 GW of WSH projects with energy storage systems currently.
WSH projects with storage are capable of catering to peak load generation, besides improving the capacity utilisation factor. Hence, these have the potential to reduce the country’s dependence on gas- and pumped hydro-based peaking plants.
In addition, CRISIL Research expects 1.1 GW of hybrid projects to come up as part of 5.4 GW up for development under the government’s round-the-clock or RTC power scheme, which has a mandatory 51:49 blend of RE and thermal.
Says Pinal Mehta, Associate Director, CRISIL Research, “As with all power projects, pricing will be key to the success of WSH projects. We expect WSH tariffs to be in the ₹ 2.8-2.9 per kWh range, with a wind-heavy WSH configuration. We believe WSH pricing will become more competitive if the co-location clause (necessitating the wind and solar components to be located at the same place) is removed.”
In the case of WSH-with-storage projects, CRISIL Research believes the weighted average tariff (peak and off-peak) of ₹ 4.04- 4.30 per kWh, as discovered in recent bids, is competitive with thermal power tariffs, which are ~₹ 4.4 per kWh.
Nevertheless, land availability and policies such as co-location will remain key monitorables for the viability of WSH projects. Other challenges, including adequate transmission infrastructure and technical issues such as grid balancing, would need to be addressed, too.