PISA Style Question
The new Hinkley Point nuclear power station
Read the text about the new Hinkley Point nuclear power station.
It is proposed that a new nuclear power station is to be built at Hinkley Point in Somerset. The power station is to be built by the French energy company EDF, backed by investment from China. The power station is to have an output power of 3200MW. The UK Government has promised the EDF/Chinese consortium that energy from the plant can be sold to the UK National Grid for 9p per kWh (a kWh is also known as a unit). This decision has proved controversial since 9p is considerably higher than the usual market rate. Environmental groups such as the Green Party argue that this represents a subsidy to the EDF/Chinese consortium by the UK government. The total cost of building the power station is estimated at £16 billion.
The cost of enriched uranium fuel is about £1500 per kg. This provides 3.7x 1012 Joules of energy per kg of uranium used. The expected life of the plant is 30 years.
Question 1 : HINKLEY POINT
The UK Government has decided to support the development of the new Nuclear Power Station at Hinkley Point. Which of the following is the best environmental reason for doing so?
A To reduce carbon dioxide emissions
B To reduce Britain’s reliance on imported gas
C To promote further business links with China
D To provide jobs for British workers
Question 2 : HINKLEY POINT
The Green Party (amongst others) have been protesting about the decision to build the power station. Which issue are they likely to be most concerned about?
A The fact that nuclear power releases no significant carbon dioxide.
B The fact that uranium is non-renewable and will run out.
C The fact that nuclear waste is radioactive and needs to be stored safely.
D The fact that there are serious safety concerns over nuclear power in the UK.
Question 3 : HINKLEY POINT
The number of units of electricity produced is calculated using the following formula:
Number of units = Power x Time
(kWh) (kW) (hours)
How many units will the power station produce in one day if it runs at full power?
A 3.2 x 24 = 76.8kWh
B 3,200 x 24 = 76,800kWh
C 3,200,000 x 24 = 76,800,000kWh
D 3,200,000,000 x 24 = 76,800,000,000kWh
Question 4 : HINKLEY POINT
1kg of coal contains about 3 x 107 J of energy and energy providers pay about 6p for each kg.
Circle ‘yes’ or ‘no’ for each statement.
Yes or No ?A kg of uranium is about 25,000 times more expensive than a kg of coal. / Yes / No
A kg of uranium provides about 10,000 times more energy than a kg of coal. / Yes / No
A kg of uranium is about 250 times more expensive than a kg of coal / Yes / No
A kg of uranium provides about 100,000 times more energy than a kg of coal. / Yes / No
Question 5 : HINKLEY POINT
From the information provided in the above article it can be shown that, if working at full power for a whole year, the Hinkley Point Power Station could genenerate about 2.8 x 1010 units of electrical energy. Which of the following is the closest estimate of how long it would take to cover the construction cost if all other costs are ignored?
A 2 Years
B 4 Years
C 6 Years
D 8 Years
Question 6 : HINKLEY POINT
Which of the following factors will also affect how long the power station takes to pay for itself? Circle ‘yes’ or ‘no’ for each statement.
Yes or No ?The cost of the uranium fuel / Yes / No
The cost of running and maintaining the power station / Yes / No
The average price of electricity per kWh in the UK / Yes / No
The cost of disposing of nuclear waste safely / Yes / No
Question 7: HINKLEY POINT
The process by which energy is produced in a nuclear reactor is known as nuclear fission. Which of the following statements correctly describes the fission process?
A Energy is released by the splitting of light nuclei.
B Energy is released by the splitting of heavy nuclei.
C Energy is released by the joining together of light nuclei.
D Energy is released by the joining together of heavy nuclei.
Question 8: HINKLEY POINT
The fission process requires the use of a moderator and control rods. Which of the following statements correctly describes their functions?
A The moderator provides neutrons with energy. The control rods give out neutrons.
B The moderator gives out neutrons. The control rods provide neutrons with energy.
C The moderator takes energy away from the neutrons. The control rods absorb neutrons.
D The moderator absorbs neutrons. The control rods take energy away from the neutrons.
Question 9: Hinkley Point
Another process with the potential to provide humans with large amounts of energy is nuclear fusion. Explain the two key differences between nuclear fission and nuclear fusion.
…………………………………………………………………………………………………………………………………..
……………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………..
…………………………………………………………………………………………………………………………………..
SCORING : HINKLEY POINT
Question 1
Full credit
A To reduce carbon dioxide emissions
No credit
Other responses
Missing
Narrative :
Only A is a valid environmental argument. The others are economic arguments.
Framework Categories / 2015 FrameworkKnowledge type / Content, epistemic
Competency
Context
Cognitive demand / Low
Question 2
Full credit
C The fact that nuclear waste is radioactive and needs to be stored safely.
No credit
Other responses
Missing
Narrative :
Response A is widely considered to be an advantage of nuclear generation over fossil fuels. B is a correct statement but would not be a concern for an environmental organisation. D is a questionable statement in the context of the UK – the safety record of UK nuclear power stations is very good.
Framework Categories / 2015 FrameworkKnowledge type / Epistemic
Competency
Context
Cognitive demand / Medium
Question 3
Full credit
C 3,200,000 x 24 = 76,800,000kWh
No credit
Other responses
Missing
Narrative :
The key demand being made on candidates is to recognise that 3200MW needs to be converted in kW by multiplying by 1000.
Framework Categories / 2015 FrameworkKnowledge type / Procedural
Competency
Context
Cognitive demand / Medium
Question 4
Full credit
Yes, No, No, Yes in that order
No credit
Other responses
Missing
Narrative :
Candidates need to calculate the ratio of £1500 to 6p which involves a unit conversion – answer 25,000. Candidates also need to calculate the ratio of 3.7 x 1012 to 3 x 107. The answer is 123,333. They also need to recognise that 100,000 is a valid approximation whereas 10,000 is not.
Framework Categories / 2015 FrameworkKnowledge type / Procedural
Competency
Context
Cognitive demand / High
Question 5
Full credit
C 6 Years
No credit
Other responses
Missing
Narrative :
Candidates are required to take the figure given of 2.8 x 1010 (they do not need to confirm it, though it can be confirmed using 3200MW and 24 x 365). This needs to be multiplied by 9p converted into £. Answer - £2.5 billion. They then need to divide £16 billion by £2.5 billion – answer 6.4.
Framework Categories / 2015 FrameworkKnowledge type / Procedural
Competency
Context
Cognitive demand / High
Question 6
Full credit
Yes, Yes, No, Yes in that order
No Credit
Other responses
Missing
Narrative :
All the factors apart from the third will incur additional costs that will impact on the payback time of the initial investment. For most power stations the wholesale cost per unit will also be relevant, but in this case candidates are told that the price guaranteed by the UK government is already considerably higher than the market rate, so 9p per unit is likely to remain constant.
Framework Categories / 2015 FrameworkKnowledge type / Epistemic
Competency
Context
Cognitive demand / High
Question 7
Full credit
B Energy is released by the splitting of heavy nuclei.
No credit
Other responses
Missing
Narrative :
This is a low demand question and simply requires the candidate to recognise the statement that describes what they have learned about the fission of Uranium 235.
Framework Categories / 2015 FrameworkKnowledge type / Knowledge of the content of science
Competency
Context
Cognitive demand / Low
Question 8 : HINKLEY POINT
Full credit
C The moderator takes energy away from the neutrons. The control rods absorb neutrons.
No credit
Other responses
Missing
Narrative :
The function of these two elements of a fission reactor is straightforward knowledge (though many GCSE candidates tend to confuse their functions).
Framework Categories / 2015 FrameworkKnowledge type / Knowledge of the content of science
Competency
Context
Cognitive demand / Medium
Question 9 : HINKLEY POINT
Full credit:
A clear statement recognising that fission involves the splitting/breaking up of a large/heavy nucleus to form smaller nuclei. Fusion involves the joining of light nuclei to form a heavier nucleus.
Partial credit
The clear statement of one of the differences, perhaps with some confusion over the other. The use of ‘atom’ instead of nucleus with both differences reasonably clearly expressed.
Framework Categories / 2015 FrameworkKnowledge type / Knowledge of the content of science
Competency
Context
Cognitive demand / Medium