Instead of working independently, the new thinking in the renewable energy sector is that solar power and wind farm projects must be developed as hybrid projects with battery backup. This strategy of joining forces, it is pointed out, can only spell good news for the energy security of the country.

“While smaller solar and wind hybrid projects have come up in the country, we will soon see larger scale solar-wind hybrids. One is a 160 MW national project with battery backup to come up in Andhra Pradesh and another one is part of a 1.2 GW tender at finalisation stage,” says Ramesh Khymal, CEO, Siemens Gamesa India (SGI), who is also chairman of CII’s renewable energy and infrastructure sub-committee.

While solar photovoltaic projects and wind farms have grown rapidly independently, the industry feels that by turning them hybrid or setting up new hybrid projects, the country could ensure near round-the-clock power. “While solar energy is harnessed between 6-7 am and 5-6 pm during the day, the wind power generation picks up after noon and goes on past midnight till 1 am. So, the gap is for a few hours and this could be bridged through a battery backup solution,” explains Khymal.

SGI has commissioned a 3.375 MW wind-solar hybrid power pilot for NTPC in Karnataka’s Bijapur district. It comprises an SG 2.0-114 wind turbine in hybrid with 1.375 MW High Efficiency HiT solar panels. This smart grid-based hybrid project is the first for NTPC. The company is also engaged in setting up a hybrid 50 MW wind plus 29 MW solar IPP project — the first commercial one in India. Apart from submitting a bid for the 160 MW wind solar hybrid project in AP where the tender is yet to be opened, Siemens is in negotiations with the winners of the first SECI hybrid tender auction for a 1.2 GW plant, where SB Energy (450 MW) and Adani (390 MW) have been shortlisted. Currently, SGI commands a domestic order book of over 1500 MW and a market share of over 30 per cent.

Offshore explorations

On the global front, Siemens Gamesa Renewable Energy recently launched a 10 MW offshore wind turbine, which has potential to increase output by 30 per cent.

The largest project in the world, it sports the SG 10.0-193 offshore wind turbine with a 193-diameter rotor. Around 20 such turbines would cover the annual electricity consumption of a city the size of Liverpool, UK.

However, where India is concerned, Khymal feels offshore projects are not viable as yet as their cost is much higher. The country should continue exploring onshore options as the potential is huge but growth has been relatively subdued.

In fact, the figures regarding wind energy speak for themselves. In 2014-15 India added about 2334 MW; 2015-16 saw 3461 MW; 2016-17 (5404 MW) and 2017-18 was a very subdued year with 1766 MW. During 2018-19, the country is likely to add about 2900-3000 MW.

As Khymal also wears the renewable industry (read CII) hat, he has several concerns about the wind energy sector. “We need better margins, they are lean. Cost of steel and other inputs has gone up after some of the contracts were signed. And in the case of the Gujarat SECI auction, it was clarified that land would have to be arranged, leading to cost escalation,” he says. Regarding the steep decline in wind power tariffs in the past, Khymal feels the trigger was a downturn in the global market and capacity lying unutilised.

But all said and done, Khymal believes the best way forward for India is by encouraging the hybrid route. “If the Government has to achieve its targets of expanding the renewable energy base, hybrids with battery backup is the way to go. This will ensure 24x7 power supply and enhanced capacity.”