Renewable & Clean Energy

Ethanol is a biofuel produced mainly by fermenting sugars found in crops like corn and sugarcane, with the USA and Brazil being the top global producers—each using a different primary feedstock. ❌ Statement I: Incorrect
* The United States is the largest ethanol producer, not Brazil. ✅ Statement II: Correct
* USA uses corn; Brazil uses sugarcane as the primary feedstock for ethanol.

Direct Air Capture (DAC) is a technology that removes CO₂ directly from the air for storage or use in various industries. ✅ Statement I is correct:
* DAC captures CO₂ for carbon sequestration, reducing greenhouse gases. ✅ Statement II is correct:
* Captured CO₂ can be used to make plastics and in food processing. ✅ Statement III is correct:
* DAC provides carbon to make synthetic low-carbon aviation fuels by combining with hydrogen. So, the correct answer is: C

Alternative powertrain vehicles are those that do not use conventional petrol/diesel engines. Instead, they rely on clean energy sources like electricity or hydrogen. * ✅ I. BEVs – Run fully on batteries and electric motors. * ✅II. FCEVs – Use hydrogen to make electricity via a fuel cell. * ✅III. FCEHVs – Combine hydrogen fuel cell + battery + electric motor. All three are alternatives to traditional fuel vehicles.

The PM Surya Ghar Muft Bijli Yojana is a major government initiative to expand rooftop solar adoption in the residential sector, while also building technical capacity across the country. ✅ Statement I: Correct
* The scheme targets the installation of 1 crore solar rooftop panels in households. ✅ Statement II: Correct
* The Ministry of New and Renewable Energy (MNRE plans to train grassroots-level workers in installation, operation, and maintenance. ✅ Statement III: Correct
* The scheme aims to create over 3 lakh skilled workers through fresh skilling and up-skilling efforts.

* Agricultural residues: These include materials like crop stalks, husks, and leaves. They are a viable source of biomass that can be converted into biofuels, including Sustainable Aviation Fuel (SAF). * Corn grain: Corn grain is a source of sugars that can be fermented to produce ethanol, a biofuel. While ethanol is primarily used in gasoline blends, it can also be further processed into SAF. * Wastewater treatment sludge: This sludge is rich in organic matter. Through processes like anaerobic digestion, it can produce biogas, which can be further converted into SAF. * Wood mill waste: This includes sawdust, wood chips, and bark. These lignocellulosic materials can be converted into biofuels through various thermochemical or biochemical processes, ultimately leading to SAF production. Therefore, all four materials can be used as feedstock for producing Sustainable Aviation Fuel.

Fuel Cell Electric Vehicles (FCEVs) powered by hydrogen generate electricity by combining hydrogen (H₂) with oxygen (O₂) in a fuel cell. This process produces electricity, heat, and the only exhaust emission is water vapour (H₂O), making hydrogen fuel cells zero-emission.

Pumped-storage hydropower (PSH) is used for long-duration energy storage. It works by pumping water to a higher reservoir during low electricity demand and releasing it to generate power during peak demand. This process helps balance the grid supply and demand, making PSH an effective tool for energy storage over extended periods. Thus, the correct answer is C.

Distributed Energy Resources (DERs) are small-scale units of power generation or storage that are situated closer to the end-users. Let's analyze each option: * Battery storage: These store energy and can be deployed within the distribution network or at the consumer end, making them DERs. * Biomass generators: These can be small-scale and located near the biomass source, making them suitable for distributed generation. * Fuel cells: Similar to biomass generators, fuel cells can be deployed in a decentralized manner, qualifying as DERs. * Rooftop solar photovoltaic units: These are a classic example of DERs, generating power at the point of consumption. _Therefore, all four options are considered Distributed Energy Resources._

* Green hydrogen is the hydrogen produced through electrolysis of water using electricity from renewable sources. * Green hydrogen is expected to play a significant role in decarbonizing all three of the mentioned heavy industries. * Green hydrogen can be used in the production of ammonia, which is a key component for many fertilizers. Fertilizer production is energy-intensive and often relies on fossil fuels, particularly natural gas. By using green hydrogen as a clean energy source, the carbon emissions from this industry can be significantly reduced * Green hydrogen can be used in oil refineries to process crude oil into various products, including gasoline, diesel, and jet fuel. This can help to reduce the carbon emissions from the refining process. * The steel industry is one of the largest industrial emitters of carbon dioxide. Green hydrogen can be used in place of coal in the steelmaking process, significantly reducing the industry's carbon emissions.

* Green hydrogen is any hydrogen that is produced from renewable energy. * Statement 1 is correct: Green hydrogen can be used as a direct fuel for internal combustion engines, replacing conventional fuels like gasoline or diesel. * Statement 2 is correct: Green hydrogen can be blended with natural gas and used as a fuel for various applications like heating, power generation, and industrial processes. * Statement 3 is correct: Green hydrogen can be used in hydrogen fuel cells to power electric vehicles, providing a clean and efficient alternative to traditional fossil fuel-powered vehicles. Therefore, all three statements regarding the uses of green hydrogen are correct.