Non-Conventional Energy Resources

Correct answer: A. Renewable resource

The governing concept is resource renewability. Wind energy comes from the movement of air, which is continually produced by atmospheric pressure differences and the uneven heating of Earth’s surface. Human use of a wind turbine does not consume the moving air in the way that burning coal consumes a finite fuel deposit. Since wind is naturally replenished on a continuing basis, wind energy is classified as a renewable resource. Therefore, option A is correct. Coal and petroleum are examples of non-renewable resources because their formation takes millions of years and their reserves are limited. Wind is not a mineral and it is not organic waste, so options C and D are unrelated.

Correct answer: A. Solar energy

The governing concept is photovoltaic conversion. Solar panels contain photovoltaic cells, usually made from semiconductor materials, that absorb sunlight and convert its radiant energy directly into electrical energy. When light reaches the cells, it causes charged particles to move, producing an electric current that can be used by appliances or stored in batteries. Therefore, option A, solar energy, is correct. Geothermal energy comes from heat inside Earth, tidal energy comes from the movement of ocean water caused mainly by gravitational forces, and wind energy comes from moving air. All three may be renewable sources, but none is the direct energy input converted by a photovoltaic solar panel.

Correct answer: A. Solar and wind energy

Solar radiation and wind are renewable energy flows that are naturally replenished and can generate electricity without burning coal, petroleum, or diesel during operation. Expanding these sources can diversify the energy mix and reduce demand for fossil-fuel-based generation, although manufacturing, land use, storage, transmission, and reliability still require careful planning. Option A is therefore correct. Coal and petroleum are themselves fossil fuels, so choosing them cannot reduce dependence on fossil fuels. Diesel generators also burn a petroleum product and generally increase direct emissions. The key distinction is between renewable energy flows and finite combustible fuels.