Global warming April 19, 2023

Learning objective: To know how global warming is effecting the earth

Key words StarterWe will gather What do you already know about these up during global warming? the starterfeedback

RespirationPhotosynthesis

Death

Decomposition

Consumed by

Decomposition

Death

Res

pira

tion

Carbon dioxide

CO2

Bur

ning

Learning objective: To know how global warming is effecting the earth

Learning objective: To know how global warming is effecting the earth

Learning objective: To know how global warming is effecting the earth

Learning objective: To know how global warming is effecting the earth

Effect of Global warming

.

Plenary

1. Describe what does this graph show?

2. Does the graph show line of best fit?

Learning objective: To know how global warming is effecting the earth

Alternative fuelsHow soon will we be using alternative fuels?

The need for alternative fuelsMost vehicles in the world use petrol or diesel as a fuel. These are produced from crude oil, a fossil fuel.

Why is it important to develop and use these fuels before oil supplies run out?

As a result, some people have already begun using alternative fuels to power their vehicles, such as biofuels and hydrogen.

Although fossil fuels are convenient sources of energy, they are very polluting, and will one day run out.

What are biofuels?

They can be safely combined with normal petrol or diesel and used in conventional engines to reduce levels of harmful emissions without causing engine damage.

Biofuels are renewable fuels produced from plant material, such as agricultural crops.

Two types of biofuel used in vehicles are bioethanol and biodiesel.

What is bioethanol?Bioethanol is an alcohol produced by the natural fermentation of the carbohydrates (such as starch) in sugar beet/cane or wheat crops.

‘Flexi-Fuel’ vehicles, fitted with modified fuel injection systems, can run on E85 fuel (85% bioethanol, 15% petrol), which cuts carbon dioxide emissions by 70% compared to normal petrol-engine cars.

What is biodiesel?Biodiesel is produced by chemically reacting vegetable oils or animal fats with alcohol and a catalyst. The process can be completed in 12 hours.

There are few garages in the UK that sell biodiesel. Home-made fuels, usually from waste vegetable oils, are heavily taxed.

Biodiesel can be mixed with conventional diesel, which significantly reduces emissions, especially toxic hydrocarbons, particulates and carbon monoxide.

Biofuels are carbon neutral: the carbon released during combustion comes from the carbon dioxide the plants took in when they were growing.

Storage, transport and distribution costs are low as biofuels can be handled in the same way as conventional fuels.

What are some of the advantages of using biofuels?Advantages of biofuels

By-products of production, such as pressed seedcake, can be burnt in power stations instead of fossil fuels or used a

animal feed.

Disadvantages of biofuels

Although biofuels themselves produce relatively little when combusted, their production needs energy from fossil fuels. There are few UK producers of biofuels, and only small

quantities of fuel are made. Biofuels therefore need to be imported, mainly from Brazil and South-East Asia.

What are some of the disadvantages of using biofuels?

The high demand for land to plant biofuel crops can lead to deforestation and habitat loss, for example in Malaysia.