The Indian government’s new wind-solar hybrid policy is likely to provide an additional thrust to increasing the installed capacity of renewable energy, although there are a few problems on the ground

Hybrid power plants that produce both wind and solar energy are set to gain ground in India (Photo by Pixabay)

The Indian government has announced a national policy for wind-solar hybrid projects, a move that industry experts said will accelerate the pace of activity in the renewables industry and go a long way in meeting the country’s target of installing 175 GW by 2022.

The Ministry of New and Renewable Energy (MNRE) on May 14 issued the National Wind-Solar Hybrid Policy. Additionally, it granted approval to auction 2.5 GW worth of wind-solar hybrid projects.

The policy will help in promoting renewables further, said Sunil Jain, CEO and Executive Director, Hero Future Energies. “While the utilisation of common resources has always been a challenge, in the long term, it will certainly aid the renewable energy sector,” he told indiaclimatedialogue.net.

Concurring, Bhaskar Deol, Founder of Mynergy Renewables India Ltd, said that while upcoming wind and solar technology deployments are still in their infancy, they have started scaling to a significant fraction of India’s total energy mix and their footprint in the form of land use and use of power evacuation infrastructure will become critical in the long term. “The hybrid policy aims at addressing this issue and paves the way towards an integrated approach for development of solar and wind energy,” he told indiaclimatedialogue.net.

“India now has more than 20 GW of solar power installations and over 30 GW of wind power installations. The power evacuation infrastructure and land for these projects can be effectively utilised if it is converted to wind-solar hybrid projects by complementing with the other resource,” said Ajith Gopi, Programme Officer at the Agency for Non-conventional Energy and Rural Technology (ANERT), Department of Power, Government of Kerala. The policy is aimed at helping increase this mix of renewable power and will also open up a new area for availability of renewable power at competitive prices along with reduced variability, provided the selected project locations have solar and wind resources, he added.

Flexible policy

“We want to ensure that this policy is not restrictive. If someone wants to install more wind and solar and deliver power, it will be promoted with this policy,” an MNRE official told indiaclimatedialogue.net. “It will provide a framework in which optimum utilisation of resources is possible, be it land, transmission and reduced variability. In the absence of a regulatory policy, hybrid plants were not being deployed. However, issuance of this policy will enable the wind-solar sector in India.”

Sunil Jain said that one of the complaints of distribution companies against renewables has been the availability of a shorter duration during the day. “For example, in India, wind generally blows from 3.30 p.m. till around 2 a.m., while solar generates power from 7.30 a.m. to 5.30 p.m. So what hybrid does is partially take care of this concern as power can be supplied from 7.30 a.m. to 2 a.m.,” he said. “Since renewables are already cheaper than coal power, this concern, when addressed, will boost the renewable energy sector. Of course, the variability concern still remains.”

Practical difficulties

Not everybody is so optimistic. Although the policy makes sense conceptually, there are many practical difficulties, according to Mudit Jain, senior manager at Bridge to India, a clean energy consultancy. “It offers no incentive or other tangible mechanism to promote hybrid technology,” he told indiaclimatedialogue.net. “Hence, its impact on the sector is hard to visualise at this stage.”

A senior MNRE official agreed partly with Mudit Jain. “This policy has a lot of issues. Where there is solar, we are looking for wind, and vice-versa. Any new project is prospective solar-wind hybrid. So, within this domain, there are three sub-categories and each sub-category has a different kind of policy challenge,” he said. “Firstly, renewable purchase obligations will have to be dealt with for solar and non-solar. Secondly, land issues will need to be tackled. Thirdly, if a hybrid plant is coming up, where there is potential from wind and solar, then what is the proportion one can go for is the question that gets thrown up.”

The policy states that its main objective is to “provide a framework for promotion of large grid-connected wind-solar PV (photovoltaic) hybrid system for optimal and efficient utilisation of transmission infrastructure and land, reducing the variability in renewable power generation and achieving better grid stability. It also aims to encourage new technologies, methods and way-outs involving combined operation of wind and solar PV plants.”

Deol says that wind-solar hybrid projects are an emerging concept, and this policy will help optimise resource use for renewables. “Hybrid projects can play a critical role in helping increase generation per sq. metre area of land utilised, achieve savings from shared generation and transmission infrastructure, and reduce operating costs,” he told indiaclimatedialogue.net.

Hybrid plants, adds Mudit Jain, can reduce variability in power output and improve grid stability as wind and solar resources often have complementary generation patterns. This is statistically correct although the benefit is hard to quantify.

Cost efficiency

Sunil Jain reasons that hybrid projects can also reduce costs further as they will have a common evacuation infrastructure. “We should aim at the optimum use of evacuation resources,” he said. “Even though extra wind land will be of limited use due to shadow effects, it will always be helpful for the industry.”

Gopi says the recent practices of using utility grade battery storage systems along with renewable power will contribute to a stable grid. “Wind-solar hybrid projects combined with battery storage will definitely be the trend in the coming days.”

It is extremely important to have wind data for the selected project site so as to ensure successful wind-solar hybridisation, he advises.

Promoting hybridisation

The policy seeks to promote new hybrid projects as well as hybridisation of existing wind and solar projects. The existing projects can be hybridised with higher transmission capacity than what was originally sanctioned, subject to availability of margin in the existing transmission capacity, it states.

Responding to whether this would help meet the target, Mudit Jain explains: “The target can be met even without the policy. There is no financial incentive on offer for promoting hybrid technology. It is almost impossible to overlay wind turbines on an operational solar site, or vice-versa. Moreover, the prospects of developing new hybrid plants are limited to select opportunistic cases and they require a greater push.”

Sunil Jain feels it will be difficult to use the existing wind projects for hybridisation as old wind projects are with a feed-in tariff regime and new costs are much lower. “All states have to come out with a hybrid policy and regulations for evacuation and metering to promote hybrid at the state level; otherwise, this policy will remain a central policy,” he told indiaclimatedialogue.net.

The biggest advantage of a hybrid plant is the lowering of power price by using a common transmission and evacuation infrastructure. For maintaining grid safety, it can’t be assumed that only a solar or wind plant will produce electricity and the system will have to planned according to the maximum capacity of the plant. Even if the developer is able to save on transmission costs, it usually account for only about 5% to 8% of the total capital cost, but it can subsequently increase the curtailment risk, says Mudit Jain.

The state regulators, Sunil Jain suggests, will have to come up with some guidelines to ensure how existing projects can be converted to hybrid and how the tariff will be worked out. “Ultimately, what they should be doing is take the new solar tariff, take a weighted average of the energy and then work out a common tariff,” he said.

Gaining ground

Recently, Hero Future Energies completed India’s first large-scale solar-wind hybrid project in Karnataka. Located at Kavithal in Raichur district, it includes an existing 50 MW wind farm and has a neighbouring 28.8 MW solar photovoltaic site to form a hybrid system. The project’s evacuation capacity remains at 50 MW since the main aim is to address grid-integration concerns around consistent power coming from the project.

Andhra Pradesh is planning to tender a project involving 120 MW of solar, 40 MW of wind and 20-40 MWh of storage this year. Meanwhile, Kerala’s ANERT is installing a pilot wind-solar hybrid project along with utility grade battery storage at Ramakkalmedu in Idukki district. “The site has got a very good potential for wind energy based on the monitoring studies conducted by ANERT with the help of National Institute of Wind Energy,” Gopi said.

“We have come out with a scheme of 2,500 MW wind-solar new projects and it was launched on May 25,” the MNRE official said. “When new projects come, we will see higher utilisation of resources and prices will come down. After the success of one or two hybrid plants, most of the wind plants will be hybrid.”