Biogas is considered to be a boon to farmers for several reasons:

1. Energy Production: Biogas provides a renewable source of energy for farmers, which can be used for cooking, heating, and lighting purposes. This reduces their reliance on traditional sources of fuel like wood, dung, or fossil fuels, thereby saving costs and reducing environmental impact.

2. Waste Management: Biogas production involves the anaerobic digestion of organic waste materials such as animal dung, crop residues, and kitchen waste. By converting these waste materials into biogas, farmers can effectively manage and dispose of organic waste while simultaneously producing energy.

3. Fertilizer Production: The byproduct of biogas production, known as digestate, is a nutrient-rich fertilizer. Farmers can use digestate to improve soil fertility and enhance crop yields, reducing the need for chemical fertilizers and promoting sustainable agriculture practices.

A solar cell panel, also known as a photovoltaic (PV) panel, is a device that converts sunlight directly into electricity using the photovoltaic effect. Three applications of solar cell panels are:

1. Residential and Commercial Solar Power Systems: Solar panels can be installed on rooftops of homes, buildings, and offices to generate electricity for on-site consumption or to feed excess power back into the grid.

2. Off-grid Power Solutions: Solar panels are used in remote areas or locations where access to traditional power grids is limited or unavailable. They provide a reliable source of electricity for powering remote homes, telecommunications equipment, water pumps, and other applications.

3. Solar-powered Gadgets and Appliances: Solar panels are used to power various gadgets and appliances such as calculators, street lights, outdoor lighting, solar-powered chargers, and solar-powered water heaters.