Green energy is a term for energy that comes from renewable sources. Green energy is often referred to as clean, sustainable, or renewable energy.

The production of green energy does not release toxic greenhouse gases into the atmosphere, meaning it causes little or no environmental impact.

Some important green energy sources include power produced by solar, wind, geothermal, biogas, low-impact hydroelectricity, and certain eligible biomass sources.

Renewable Energy:

• Sustainable: Energy generated from renewable sources will be cleaner and greener and more sustainable.
• Employment opportunities: Inclusion of a newer technology simply means more employment opportunities for the working population of the country.
• Market assurance: From the economy point of view, renewable sources provide the market and revenue assurance which no other resources can provide.
• Power supply: Providing 24*7 power supply to 100% of the households, sustainable form of transports are some of the goals that can only be achieved through sustainable power that comes from renewables.

 Solar Energy:

• India is one of the few countries that has long days and plenty of sunshine by nature.
• We can generate electricity from solar energy in two ways:
  • Photovoltaic Electricity – generates electricity by absorbing direct sunlight through photovoltaic cells.
  • Solar-Thermal Electricity – A solar collector with a mirrored surface reflects sunlight onto a receiver, which heats a liquid. This heated liquid is used to produce steam, which generates electricity.

Wind Energy:

• Wind energy is the kinetic energy associated with atmospheric air movement.
• Wind turbines convert wind energy into mechanical power, which is then converted to electric power to generate electricity.
• Germany, the United States, Denmark, Spain, and India account for 80% of the world’s installed wind energy capacity.

Wind Farm:

• Wind farms are places with a significant number of huge wind turbines clustered together.
• They “harvest” the wind’s energy. These massive turbines resemble super-tall windmills in appearance.
• Hundreds of wind turbines can be spread out over hundreds of kilometers in a huge wind farm.
• The land in between the turbines could be used for anything else, like conventional farming.
• Some wind farms are built near bodies of water as well. They use the breezes that blow across lakes or oceans to their advantage.

Types of Wind Farm:

Onshore Wind Farms:

• Onshore wind energy refers to wind turbines that are positioned on land and generate electricity using the wind.
• They’re usually found in places with little conservation or habitat value.

Offshore Wind Farms:

• Offshore wind power, also known as offshore wind energy, is when the wind is utilized to create electricity over open water, usually in the ocean.
• Wind farms are built in areas with higher wind speeds, such as bodies of water.

Hydro Power:

• Hydropower is the use of water’s natural force to generate electricity (kinetic energy).
• Hydroelectric systems capture the energy and convert it to power using a turbine and generator.
• Because the sun replenishes the water supply, hydropower is regarded as a renewable energy source. This implies that it is a limitless resource.
• It’s also environmentally friendly because it doesn’t produce greenhouse gases, which contribute significantly to pollution and global warming.
• Today, China is the world’s greatest hydropower generator, followed by Canada, Brazil, and the United States.
• Hydropower is expected to be the world’s dominating energy resource for many years to come due to its abundance.

Types of Hydropower Plant:

• Impoundment Hydropower Plant
• Diversion Hydropower Plant
• Pumped storage Hydropower Plant

Ocean Thermal Energy:

• Large amounts of solar energy are stored in the oceans and seas. The tropical seas absorb solar radiation equivalent to the heat content of 245 billion barrels of oil on average.
• The process of harnessing this energy is known as OTEC (ocean thermal energy conversion).
• It uses temperature differences between the ocean’s surface and depths of about 1000 metres to power a heat engine, which generates electricity.

Biomass:

• Biological material, such as that found in plants and animals, is what is referred to as organic material, or biomass.
• Plants, wood, and waste are the most common biomass materials used for energy. They are referred to as biomass feedstocks.
• A non-renewable energy source that uses biomass is also possible.
• The energy in biomass is initially obtained from the sun: through photosynthesis, plants transform carbon dioxide and water into nutrients (carbohydrates).
• Both direct and indirect methods can be used to convert the energy from these creatures into useable energy.
• Direct combustion of biomass can provide heat, direct conversion of biomass to electricity, or direct conversion of biomass to biofuel (indirect).

Cogeneration:

• The sequential generation of two separate forms of usable energy from a single primary energy source, often mechanical and thermal energy, is known as cogeneration or combined heat and power (CHP).
• Mechanical energy can be utilized to power an alternator, which generates electricity, or to power rotating equipment, such as a motor, compressor, pump, or fan, which provides a variety of services.
• Thermal energy can be used directly in processes or indirectly to generate steam, hot water, hot air for dryers, or chilled water for process cooling.
• Cogeneration, in practice, comprises the use of otherwise lost heat (such as a manufacturing plant’s exhaust) to generate additional energy benefits, such as providing heat or power for the building in which it is running.
• Cogeneration is beneficial to both the bottom line and the environment, as it avoids the use of polluting fossil fuels by recycling waste heat.

Waste to Energy:

• Waste-to-energy (WtE) is a term that refers to the process of using waste to generate energy in the form of electricity, heat, or fuels.
• Modern waste-to-energy facilities differ from traditional trash incinerators in that the latter do not remove hazardous or recyclable materials before burning.
• Although the majority of waste-to-energy plants burn municipal solid trash, some also burn industrial or hazardous waste.
• A contemporary, well-run waste-to-energy facility separates rubbish before burning it, and recycling can coexist.

Geothermal Energy:

• Geothermal energy is natural heat derived from the earth’s interior that can be used to generate electricity and heat structures.
• A layer of hot, molten rock called magma exists beneath the earth’s crust.
• The decay of naturally radioactive materials like uranium and potassium produces heat in this layer on a continuous basis.
• Heat within 10,000 meters (33,000 feet) of the earth’s surface contains 50,000 times more energy than all of the world’s oil and natural gas reserves combined.
• There are three types of geothermal resources: geopressurized zones, hot-rock zones and hydrothermal convection zones.
• Only the first of these three is currently being commercially exploited.
• Hot Springs, Geysers and Lava Fountain are some natural examples of geothermal energy.
• According to the Ministry of New and Renewable Energy, geothermal resources in India have been mapped, and as per general estimates there could be a 10 gigawatt (GW) geothermal power potential.

Fuel Cells:

• A fuel cell is a device that uses a chemical reaction to generate electricity.
• A positively charged ion (Hydrogen) and an oxidizing agent (oxygen) are used in fuel cells.
• Fuel cells come in a variety of shapes and sizes, but they all have a cathode, an anode, and an electrolyte that permits positively charged (hydrogen) ions to travel between the two sides.
• Fuel cells differ from batteries in that they require a constant source of fuel.
• Direct current (D.C) is produced by both batteries and fuel cells

Green hydrogen:

Hydrogen when produced by electrolysis using renewable energy is known as Green Hydrogen which has no carbon footprint.

• The hydrogen that is in use today is produced using fossil fuels, which is the primary source.
• Organic materials such as fossil fuels and biomass are used for releasing hydrogen through chemical processes.

Significance of Green Hydrogen:

• Green hydrogen energy is vital for India to meet its Nationally Determined Contribution (INDC)Targets and ensure regional and national energy security, access and availability.
• Green Hydrogen can act as an energy storage option, which would be essential to meet intermittencies (of renewable energy) in the future.
• In terms of mobility, for long distance mobilisations for either urban freight movement within cities and states or for passengers, Green Hydrogen can be used in railways, large ships, buses or trucks, etc.

 Applications of green hydrogen:

• Green Chemicals like ammonia and methanol can directly be utilized in existing applications like fertilizers, mobility, power, chemicals, shipping etc.
• Green Hydrogen blending up to 10% may be adopted in CGD networks to gain widespread acceptance.

India has set a target to reduce the carbon intensity of the nation’s economy by less than 45% by the end of the decade, achieve 50 percent cumulative electric power installed by 2030 from renewables, and acheve net-zero carbon emissions by 2070

Renewable Energy – Benefits:

• Private-sector opportunity: PM indicated the possibility of a $20 billion-per-year business in the renewable energy sector.
  • A target of 450 GW of renewable energy capacity by 2030 implies that we must add nearly 25-30 GW of renewable energy capacity per year.
  • The private sector can capitalise on this as a high return on investment opportunity.
• Low maintenance costs: When compared to traditional energy sources such as coal-based or oil-based thermal power plants, solar energy has the advantage of almost no need for fuel procurement as well as less wear and tear due to the lack of movement of parts.
• Government incentives: Renewable energy will always be incentivized to invest additional resources and create more energy capacity.
• Sustainability: Because renewable energy is a cleaner source of pollution, it benefits the environment in general while also reducing pollution and the diseases associated with it.
• Atmanirbhar Bharat: Private sector investment in renewable energy would also help the government achieve its goal of self-reliance. It will also generate job opportunities in the country.
• Last-mile connectivity: Because renewable energy can be decentralised, it is better suited to extending last-mile connectivity in remote areas where stretching the main grid may not be financially feasible.
  • This is also cost-effective for the government and citizens because decentralised connectivity reduces transmission and distribution losses.

Some Government’s Initiatives for generating Renewable Energy:

Grid Connected Solar Rooftop Programme:

Objective: For achieving cumulative capacity of 40,000 MW from Rooftop Solar (RTS) Projects by the year 2022.

Solar Park Scheme:

MNRE has come up with a scheme to set up a number of solar parks across several states, each with a capacity of almost 500 MW. The scheme proposes to offer financial support by the Government of India to establish solar parks to facilitate the creation of infrastructure required for setting up new solar power projects in terms of allocation of land, transmission, access to roads, availability of water, etc.

International Solar Alliance:

The International Solar Alliance (ISA) is an alliance of 121 countries initiated by India, most of them being sunshine countries, which lie either completely or partly between the Tropic of Cancer and the Tropic of Capricorn. The primary objective of the alliance is to work for efficient consumption of solar energy to reduce dependence on fossil fuels.

The initiative was launched by Prime Minister Narendra Modi at the India Africa Summit, and a meeting of member countries ahead of the 2015 United Nations Climate Change Conference (COP 21) in Paris in November 2015. The framework agreement of the International Solar Alliance opened for signatures in Marrakech, Morocco in November 2016, and 200 countries have joined.

HQ– Gurugram, Haryana

PM KUSUM:

Pradhan Mantri Kisan Urja Suraksha evem Utthan Mahabhiyan (PM KUSUM) Scheme for farmers aims for installation of solar pumps and grid connected solar and other renewable power plants in the country.

The scheme aims to add solar and other renewable capacity of 25,750 MW by 2022.

National Green Corridor Project:

The green energy corridor is grid connected network for the transmission of renewable energy produced from various renewable energy projects.

National Wind-Solar Hybrid Policy:

This policy essentially aims at establishing a structure on the basis of which large-scale wind-solar hybrid power projects can be promoted.

National Offshore Wind Energy Policy:

The objective is to develop the offshore wind energy in the Indian Exclusive Economic Zone (EEZ) along the Indian coastline.

Sustainable Rooftop Implementation for Solar Transfiguration of India (SRISTI) scheme:

The Central government will offer with financial incentive to the beneficiary for installing Solar power plant rooftop projects within the country.

Biomass power & cogeneration programme:

It is being implemented with the main objective of promoting technologies for optimum use of country’s biomass resources for grid power generation.

Draft National Wind-Solar Hybrid Policy:

The main objective of the Policy is to provide a framework for promotion of large grid connected wind – solar PV hybrid system for optima l and efficient utilization of transmission infrastructure and land, reducing the variability in renewable power generation and achieving better grid stability.

FDI Policy:

100% FDI is allowed in the renewable energy sector under the Automatic route and no prior Government approval is needed.

Akshay Urja Portal and India Renewable Idea Exchange (IRIX) Portal:

Promotes the exchange of ideas among energy conscious Indians and the Global community.

National Biogas and Manure Management Programme:

Central Sector Schemes that provides for setting up of Family Type Biogas Plants mainly for rural and semi-urban/households.

Production Linked Incentive (PLI) Scheme:

Incentives for High Efficiency Solar PV Modules for Enhancing India’s Manufacturing Capabilities and Enhancing Exports.

Challenges in the renewable energy sector for sustainable development:

Despite the progress India has made in developing the renewable energy sector, the country still faces barriers. Offtaker risk, lack of infrastructure, lack of financial intermediaries, and limited understanding from investors are the four main challenges to overcome.

Offtaker risk: This refers to the risk that the buyer may not fulfill the contractual obligations or will delay or make incomplete payments. Offtakers are primarily state-owned public-sector distribution companies. Given the poor financial health of India’s distribution companies, there is a risk of lagged or incomplete payments. In 2015 the total outstanding debt of distribution companies was approximately $64 billion. Offtaker risk increases the overall risk of the renewable energy projects. To address this issue, the government has implemented Ujwal DISCOM Assurance Yojana, which aims at reducing operational inefficiencies and improving the financial performance of distribution companies. The program mandates to take over 75% of distribution company debt and turn it into state-guaranteed bonds.

Lack of infrastructure: Inefficiencies from the lack of infrastructure to generate and distribute electricity are a key barrier to foreign investment. Moreover, the time taken to obtain permits for building and operating the transmission evacuation infrastructure is very long. These delays increase project construction time, which postpones the commissioning of new projects and ultimately revenues and profits.

Lack of financial intermediaries: Another barrier for Indian institutional investors is a shortage of financial intermediaries in the renewable energy sector. These actors are needed to provide proper information about investment opportunities.

Limited understanding: Renewables lie outside traditional investments, and potential investors are often wary because of their limited understanding of the sector. Domestic institutional investors typically invest in less risky securities and prefer more liquid assets with good credit ratings, which are not available in renewable energy projects.

With a total renewable energy installed capacity of 20 GW and contributing nearly 12 percent of the total renewable power generation, Tamil Nadu is amongst the leading States in the Renewable Energy sector in the country.

Offshore Wind Energy Potential of 35GW:

Tamil Nadu, being an industrialized and urbanized State, has 4^th highest peak energy demand in the country. It has highest energy consumption among the Southern States. The total installed capacity of Power in Tamil Nadu stands at 34,706.16 MW as on 01.04.2023, of which, 8,739.01 MW i.e. 25.18% from Wind, 6,539.23 MW i.e., 18.84% from Solar, 164.84 MW i.e. Tamil Nadu stands first in installed wind capacity in India. The State has the total installed wind capacity of 10,067.20 MW (State capacity – 8,739.01 MW and CTU capacity – 1,328.19) as on 01.04.2023, which is 24% of the Nation’s wind power capacity. The maximum wind power of 5,689 MW was harnessed on 03.07.2022 and the maximum wind energy generated and absorbed was 120.25 MU on 09.07.2022.1.51 % from Co-generation which are renewable sources of energy

The State stands fourth highest in installed Solar capacity in India. It has an installedcapacity of 6,689.23 MW (State Capacity – 6,539.23 MW and CTU capacity – 150 MW) as on 01.04.2023. The maximum solar power of 4,866 MW was harnessed on 26.02.2023, and the maximum solar energy generated and absorbed was 36.0 MU on 25.02.2023.

Government has also set up the Tamil Nadu Governing Council on Climate Change, the first such to be headed by a Chief Minister. The council will provide policy guidance to the Tamil Nadu Climate Change Mission, provide advice on adaptation to climate change and mitigation of climate change impacts, formulate the Tamil Nadu State Climate Change Action Plan and provide appropriate guidelines for its implementation.