Hydrogen Based Energy

**Statement 1 is correct:** When pure hydrogen reacts with oxygen in a fuel cell, the only byproducts are water and heat. This is an advantage of hydrogen fuel cells, making them a clean energy source with minimal emissions. **Statement 2 is incorrect:** Fuel cells can be used for various applications, including powering small devices like laptops. Portable fuel cells are being developed for this purpose. While currently less common, they hold promise for the future. **Statement 3 is incorrect:** Fuel cells actually produce electricity in the form of Direct Current (DC). In some applications, an inverter might be needed to convert the DC output to AC for compatibility with the electrical grid. Therefore, the only correct answer is 1 only.

**Statement 1 is incorrect:** While H-CNG significantly reduces carbon monoxide (CO) emissions, it does not eliminate them entirely. Burning hydrogen produces only water vapor, but since H-CNG is a blend of hydrogen and CNG, some CO is still emitted though at lower levels than conventional CNG. **Statement 2 is correct:** H-CNG is cleaner than CNG, leading to a reduction in carbon dioxide (CO₂) and hydrocarbon (HC) emissions. The reduction depends on the specific blend ratio and engine efficiency. **Statement 3 is correct:** As per Indian government guidelines, up to 18% hydrogen (by volume) can be blended with CNG for use in buses and other vehicles. This blend improves combustion efficiency and reduces emissions. **Statement 4 is incorrect:** H-CNG is not necessarily cheaper than CNG. The cost is influenced by Hydrogen production methods, Infrastructure development and Blending technology. Therefore, option (B) statements 2 and 3 are correct.

* 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.**