Topic : Renewable hybrid energy systems as a game changer
Topic in Syllabus: General Studies Paper 3: Indian Economy
Two recent auctions for wind/solar hybrid projects conducted were under-subscribed. However, we can believe that renewable hybrids can play a key role in helping India accelerate the decarbonization of power generation and lowering the cost of electricity in the medium term.
Hybrid power system:
A combination of different but complementary energy generation systems based on renewable energies or mixed (RES- with a backup of Liquefied Petroleum Gas (LPG)1/ diesel/gasoline genset), is known as a hybrid power system (“hybrid system”).
Significance of Renewable hybrid energy
- Off grid renewable energy technologies satisfy energy demand directly and avoid the need for long distribution infrastructures.
- Environmentally friendly power generation technologies will play an important role in future power supply. The renewable energy technologies include power generation from renewable energy sources, such as wind, PV(photovoltaic), MH(micro hydro), biomass, ocean wave, geothermal and tides.
- Since the Renewable energy resources are intermittent in nature therefore, hybrid combinations of two or more power generation technologies, along with storage can improve system performance.
Challenges faced by Renewable energy
- It relies on intermittent sources, producing energy only when the sun is shining or the wind is blowing.
- Its output is constrained to specific hours of the day.
- Its use leads to lower utilization of transmission lines. This can create issues in matching peak power demand with renewable output and raise the costs of transmission.
- Solar and wind power are not as easy to control as traditional fossil fuel plants, so power grids need to become flexible enough to handle last-minute changes in power generation.
- Countries with renewable energy penetration of 15% indicate that flexible energy resources that can rapidly ramp up or down are needed. These could include hydro or gas-based power, or energy storage solutions.
- Distance is also an issue. In India, six states in the western and southern regions account for 80 percent of all of the country’s currently installed solar capacity, but only 38 percent of power demand.
- Renewable Energy as deployed today helps meet an energy need (kWh), but doesn’t help meet the peak by contributing capacity (kW) at the right time, which is India’s main challenge.
- Rooftop solar is far, far behind schedule to meet the 40GW goal. While small deployments naturally cost more than grid-scale farms, we have to dig deeper into who would install such systems.
How Renewable hybrids can be a solution?
- A hybrid system can combine wind, solar with an additional resource of generation or storage.
- In India, solar output is maximum between 11am and 3pm, while wind output is highest in the late evening and early morning.
- Peak demand for power is reached in the evening hours of 6-9pm, which cannot be catered to by either wind or solar.
- If we can store some energy during excess renewable generation hours and release it into the grid during peak demand hours, the combined “hybrid” system can produce 24×7 clean energy as per varying levels of demand in the day.
- The storage can take many forms, such as batteries, pumped hydro or mechanical storage through the flywheel.
- Hybrid systems can address limitations in terms of fuel flexibility, efficiency, reliability, emissions and / or economics.
- Incorporating heat, power, and highly efficient devices (fuel cells, advanced materials, cooling systems, etc.) can increase overall efficiency.
- An optimal combination of solar, wind and storage can deliver stable round-the-clock power at today’s costs of around ₹6-7/kWh. Though this is significantly higher compared to baseload coal plants, lithium-ion battery costs are expected to fall from current $220-240/kWh to below $100 in the next 3-4 years.
- Costs of solar energy have fallen from ₹4.63/kWh in 2016 to ₹2.50/kWh in the latest auctions and may fall as low as ₹2/kWh in the next 3-5 years.
- McKinsey’s proprietary modeling suggests that if the above improvements are factored in, wind-solar storage hybrid systems could generate round-the-clock power with cost as well as reliability levels comparable to existing coal-fired power plants in the next 4-5 years.
- Hybrid systems capture the best features of each energy resource and can provide “grid-quality” electricity, with a power range between 1 kilo watts (kW) to several hundred kilo watts.
- They can be developed as new integrated designs within small electricity distribution systems (mini-grids) and can also be retrofitted in diesel based power systems.
- Hybrid systems can provide a steady community-level electricity service, such as village electrification, offering also the possibility to be upgraded through grid connection in the future.
- Rapid depletion of fossil fuels has necessitated an urgent need for alternative sources of energy to cater the continuously increasing energy demand. Another key reason to reduce our consumption of fossil fuels is the growing global warming phenomena.
Role played by Government towards Hybrid energy:
- India’s ministry of new and renewable energy released a solar-wind hybrid policy in 2018.
- This provides a framework to promote grid-connected hybrid energy through set-ups that would use land and transmission infrastructure optimally and also manage the variability of renewable resources to some extent.
- The Central Electricity Authority and CERC shall formulate necessary standards and regulations including metering methodology and standards, forecasting and scheduling regulations, REC mechanism, grant of connectivity and sharing of transmission lines, etc. for wind-solar hybrid systems
- For wind turbines, solar modules and balance of systems, the technical guidelines issued by the Ministry from time to time for grid connected systems will be followed.
- India has added 65-70GW of wind and solar capacity so far, with wind and solar contributing 9.5% of generated energy in May 2019. If the government target of 175GW is achieved by 2022, this share could exceed 15-16%.
- India is not the only country planning hybrid projects; 50-plus hybrid projects of MW-scale have already been announced or are under construction globally, with Australia and US being the leaders.
- If the economics of hybrid systems do approach the above levels, analysis indicates that they can potentially be competitive with 30-40% of existing coal-fired stations in India.
- Reaching the non electrified rural population is currently not possible through the extension of the grid, since the connection is neither economically feasible, nor encouraged by the main actors.
- policy and regulatory changes need to be made so that India can fully capture the potential of this interesting disruption in the energy sector.
Should India continue to build new coal-fired plants to meet base load requirements, or could renewable hybrids take a significant share? Elucidate