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Energy flow Part 2
Energy flowPart 2
How do we use biomass?Biomass supplies us with more than just food.
How can biomass be used by humans?
Starter
Energy flowLearning objectives Success criteriaStudent will learn about:
Biomass
Biofuels
How biogas is formed
Students can: Recall examples of
fuels
Describe the different methods of transferring energy from biomass
Explain the reasons for developing biofuels
What is biomass energy?Biomass energy is one of the oldest forms of energy.
The biomass stored in wood can be burned for heating and cooking.
Animal dung can also be burned for energy.
Biofuels Biofuels release smaller amounts of carbon
dioxide than conventional fuels when burnt. e.g. Drax power station CO2 output reduced 5%
when Elephant grass is burnt instead of coal
In Lille, France the buses run on biogas.
In Britain 2% of fuel sold is biogas.
Advantages of biofuelsRenewable.
Cause less pollution.
Help towards a countries energy self reliance.
Task - BiofuelsAnswer questions 9 – 16 on page 74 – 75 of the textbook
9. From the sun10. To make food so that it can grow11. Biomass12. Energy is released (and pollutants)13. Because fossil fuels produce a lot of carbon dioxide,
which is linked to global warming14. Methane and some carbon dioxide15. Biogas produces less harmful waste gases than petrol16. So they can be replaced quickly
More than our fair share?Biofuels have many advantages but using land to grow fuel reduces the area available for food crops.Humans take the biggest slice of the Earth’s resources, using about 40% of the biomass produced on land. How would growing biofuels affect this?
Should humans leave more biomass for other organisms?
Task Answer questions 17 – 18 on p75 of textbook
17. Fossil fuels have a lot of energy but produce a lot of harmful waste, they are also not being replaced; Biogas is cleaner and is easily replaced but does
notproduce as much energy.
18. In a drought, the farmer may have to use his crops to feed his family; he will have no seeds to sell or plant the following year.
PlenaryOne answer to the diminishing fuel resources may be to reduce the amount of energy we use.
List ways you could reduce energy use at school and home.
Energy flowLearning objectives Success criteriaStudent will learn about:
Biomass
Biofuels
How biogas is formed
Students can: Recall examples of
fuels
Describe the different methods of transferring energy from biomass
Explain the reasons for developing biofuels
