Why is there a need to harness non-conventional sources of energy? Give two main reasons.
Our demand for energy is increasing to improve quality of life and support population growth.
Fossil fuels are limited and may not last long.
Write two different ways of harnessing energy from ocean.
Tidal energy
Wave energy or Ocean Thermal Energy Conversion (OTEC)
What steps would you suggest to minimise environmental pollution caused by burning of fossil fuels?
Use smokeless appliances to reduce smoke pollution.
Promote afforestation to improve air quality.
What is the role of a plane mirror and a glass sheet in a solar cooker?
The plane mirror acts as a reflector to focus sunlight into the cooker.
The glass sheet traps heat inside the cooker and produces greenhouse effect.
Mention three advantages of a solar cell.
Solar cells have no moving parts.
They require little maintenance.
They can be set up in remote areas.
What is biomass? What can be done to obtain bio-energy using biomass?
Biomass consists of plant and animal wastes.
Bio-energy can be obtained by using biomass in a biogas plant.
What are the limitations in obtaining energy from wind?
Wind energy is erratic and cannot be harnessed continuously.
Large open areas are needed for setting up wind farms.