Storage Options for Renewable Energy

In News

• Recently, the Government has started exploring storage options as the share of renewables increases in the grid.

Key Points

• Current Scenario: 
  • To operationally sustain a huge monthly addition of an average 1,000 megawatt from non-fossil fuels or renewables to the electricity grid, India needs to urgently work on developing viable energy storage options.
  • The amount is almost five times the amount of power a 250 MWe nuclear plant produces.
• Producer: 
  • India is the world’s third largest producer of renewable energy.
  • Nearly 40 per cent of installed electricity capacity comes from non-fossil fuel sources. 
  • This green push has resulted in a sharp 24 per cent reduction in emission intensity of GDP between 2005 and 2016, but it has also thrown up challenges of a grid being increasingly powered by renewables.
• Alternative to Lithium Ion Batteries:
  • Even as the Lithium-ion storage battery option for grid application is now being ruled out as unviable, at least for now, an emerging policy resolution is that solar and wind-based generation cannot continue to be pushed down to struggling electricity distribution companies or discoms. 

About Solar Energy 

• Solar energy is any type of energy generated by the sun.
• Solar energy is created by nuclear fusion that takes place in the sun. 
  • Fusion occurs when protons of hydrogen atoms violently collide in the sun’s core and fuse to create a helium atom. 
• India had committed to installing 175,000 MW of renewable energy by 2022 of which 100,000 MW was to be solar power. 
• As of October 2022, 61,000 MW of solar power had been installed so far.

Major Programmes in Renewable Energy Sector 

• National Solar Mission (NSM) 
  • The NSM was launched with the objective of establishing India as a global leader in solar energy, by creating the policy conditions for solar technology diffusion across the country.
  • The initial target of NSM was to install 20 GW solar power by 2022. 
  • This was upscaled to 100 GW in early 2015. 
• Pradhan Mantri Kisan Urja Suraksha evam Utthaan Mahabhiyan (PM-KUSUM) 
  • It was launched in 2019 and it aims to help farmers access reliable day-time solar power for irrigation, reduce power subsidies, and decarbonise agriculture. 
  • PM-KUSUM provides farmers with incentives to install solar power pumps and plants in their fields. 
• Atal Jyoti Yojana (AJAY) Phase-II
  • A Scheme for the installation of solar street lights with 25% fund contribution from MPLAD Funds. 
• Solar Parks Scheme
  • Solar parks provide solar power developers with a plug and play model, by facilitating necessary infrastructure like land, power evacuation facilities, road connectivity, water facility etc. along with all statutory clearances.

Challenges 

• Non-availability of natural gas to run gas turbines:
  • It complements the growing RE capacity in the generation mix. 
  • India’s vast fleet of coal-based power plants of 200 MW series are more than 25 years old, run on old technology and do not promise robust reliability. 
• India’s heavy load: 
  • The load demand is far from saturated.
  • There is the need to replace obsolete coal-based plants with supercritical highly-efficient coal-based plants as an intermediate goal for total transition. 
  • However, this may not be acceptable to the international community in view of the impending climate crisis.
• Coal based usage reduction: 
  • There is an urgent need to reduce the percentage of coal-based capacity by closing the inefficient fleet
  • And simultaneously add new flexible capacity to meet load requirements. 
  • Newer technologies or avenues are needed which can convert coal-based capacity to a fuel mix of gas and hydrogen.
• Storage capacity & flexibility of thermal power plants: 
  • Thermal power plants need to be flexible up to 55 per cent and in coming phases, after three years, go down to 40 per cent.
  • Battery storage is expensive at Rs 10 per kilowatt per hour. There is a fresh impetus required to pursue pumped hydro projects so as to reduce costs.
• Reduced scope to go renew: 
  • The renewables challenge is compounded by the fact that SECI (Solar Energy Corporation of India Ltd) has locked a number of contracts involving green developers in rigid PPAs (power purchase agreements) with no scope for innovation.

Way Ahead

• Hydrogen and hybrid generation models blended with off-stream pumped storage:
  • Stepping up green hydrogen production and tapping into its potential as a fuel should be expedited. 
  • All pumped hydro sites and hydro PSUs have been given a target of taking up pumped hydro schemes. 
  • There should be opencast mines as potential sites for pumped hydro in the future.
• Energy storage:
  • It is needed alongside green energy sources to primarily balance out the variability in renewable generation – electricity is generated only when the sun shines or when the wind blows. 
  • This is not always in sync with the demand cycle. 
  • Storage can help tide over this shortcoming associated with renewables.
• Renewables bundled with a viable storage option:
  • For procurers such as state-owned discoms, renewables are not always a viable option precisely due to these vagaries in the generation trends, which means they still have to depend on thermal or nuclear generation for meeting base load demand. 
  • This option will help overcome this problem.

Source: IE