能源资源与发电
爱德思国际普通中等教育证书(IGCSE)物理· 4.18P-4.19P· 12 分钟阅读
1. 1. 可再生与不可再生能源的分类★★☆☆☆HL 专属⏱ 3 min
✓ 计算器
所有发电用能源资源都被划分为两大核心类别,该分类区别几乎在本专题的每一道考题中都会涉及。
可再生能源资源
补充速度快于消耗速度,因此在数千年甚至更长时间内都不会耗尽的能源资源。
例:
Wind, hydroelectric, geothermal, solar
不可再生能源资源
总量有限,消耗速度快于自然生成速度,最终会完全耗尽的能源资源。
例:
Fossil fuels (coal, oil, gas), nuclear (uranium)
将以下能源分类为可再生或不可再生:天然气、地热能、太阳能电池、煤炭、水能。
- 1
- 识别补充速度快于消耗速度的资源:地热能、太阳能电池、水能 → 可再生能源
- 2
- 识别消耗速度快于生成速度的有限资源:天然气(化石燃料)、煤炭(化石燃料)→ 不可再生能源
2. 2. 发电方式的能量传递链★★★☆☆HL 专属⏱ 4 min
✓ 计算器
你必须牢记每种发电方式对应的准确能量传递链,这类内容经常出现在1-2分的简答题中。请务必写出每一个中间能量储存形式,不能只写起点和终点。
Generation Method | Full Energy Transfer Chain |
|---|---|
Wind | Kinetic store (moving air) → Kinetic store (turbine blades) → electrical energy |
Hydroelectric | Gravitational potential store (water at height) → Kinetic store (falling water/turbine) → electrical energy |
Geothermal | Thermal store (hot underground rock) → Kinetic store (steam/turbine) → electrical energy |
Solar heating system | light energy (sunlight) → Thermal store (water/air) |
Solar cell (photovoltaic) | light energy (sunlight) → electrical energy |
Fossil fuel power station | Chemical store (fuel) → Thermal store (steam) → Kinetic store (turbine) → electrical energy |
Nuclear power station | Nuclear store (uranium) → Thermal store (steam) → Kinetic store (turbine) → electrical energy |
写出燃煤发电站发电的完整能量传递链。
- 1
- 从初始能量储存形式开始:煤炭属于化石燃料,因此是煤炭的化学能储存
- 2
- 煤炭燃烧将水加热为水蒸气:化学能储存 → 水蒸气的热能储存
- 3
- 水蒸气推动涡轮机转动:热能储存 → 涡轮机的动能储存
- 4
- 涡轮机驱动发电机产生电能:动能储存 → 电能
3. 3. 大规模发电的优缺点★★★☆☆HL 专属⏱ 4 min
✓ 计算器
分值为3-4分的评估题要求你判断某一种发电方式在特定场景下的适用性。只有给出与成本、污染、可靠性和土地利用相关的、全面且有依据的观点才能获得满分。
评估在沿海地区使用风力涡轮机进行大规模发电的优劣。
- 1
- 阐述优势:风能属于可再生能源,不会耗尽;运行过程中不会释放二氧化碳或污染气体;沿海地区持续保持较高风速,因此发电量相对可靠。
- 2
- 阐述劣势:风力涡轮机会产生噪音,对当地居民造成视觉侵扰;无风日发电量会降至零;需要占用大量陆地或近海空间。
- 3
- 平衡结论:只要当地社区可以接受风力发电机带来的视觉影响和噪音影响,风力发电机就是沿海地区的合适选择。
Nuclear power key pros: No CO2 emissions during operation, very high energy output per kg of fuel, reliable 24/7 output
Nuclear power key cons: High construction and decommissioning costs, produces long-lived radioactive waste that requires secure storage
Fossil fuel key pros: Low construction cost, reliable output regardless of weather, can be scaled up to meet high demand
Fossil fuel key cons: Releases CO2 that contributes to climate change, releases sulfur dioxide that causes acid rain, finite resource that will run out
4. 4. 考试练习与知识回顾★★☆☆☆HL 专属⏱ 1 min
✓ 计算器
该知识点在试卷2中占总分值的3%-5%,对应题型涵盖1分的选择题到4分的拓展问答题。在继续学习之前,请通过下方的概念检测题检验你的掌握程度。
Which of the following is the correct energy chain for a solar cell?
A) Light → thermal → electrical
B) Light → electrical directly
C) Thermal → electrical
D) Chemical → electrical
显示答案
B —Solar cells are photovoltaic, converting sunlight directly to electricity with no intermediate thermal step.
Which of the following is a key disadvantage of nuclear power?
A) Releases CO2 during operation
B) Low energy output per kg of fuel
C) Produces long-lived radioactive waste
D) Is a renewable resource
显示答案
C —Nuclear power produces radioactive waste that must be stored safely for thousands of years, a key downside of the technology.
5. 常见陷阱
错误做法:
Confusing solar cells and solar heating systems, writing that solar cells produce thermal energy
原因:
Students mix up the two solar technologies, leading to lost marks on transfer chain and classification questions
正确做法:
Memorize: solar cells = light → electrical directly; solar heating = light → thermal
错误做法:
Omitting intermediate energy stores in transfer chains, e.g. writing 'wind → electricity' instead of the full chain
原因:
Exam marks require all key stores to be named, not just the start and end points
正确做法:
List every energy store in order, including the kinetic store of the turbine for all rotating generation methods
错误做法:
Classifying nuclear power as a renewable resource
原因:
Students assume no CO2 emissions = renewable, but uranium is a finite resource
正确做法:
Only wind, water, geothermal and solar are renewable; fossil fuels and nuclear are non-renewable
错误做法:
Claiming nuclear power releases CO2 during operation
原因:
Students confuse nuclear with fossil fuel generation
正确做法:
Nuclear power produces no CO2 or polluting gases during operation; emissions only occur during construction, mining and decommissioning
错误做法:
Giving unbalanced answers for evaluation questions, e.g. only listing advantages of renewable energy
原因:
Evaluation questions explicitly require balanced arguments to get full marks
正确做法:
Always give an equal number of advantages and disadvantages matching the question's mark allocation
6. 速查表
Generation Method | Classification | Energy Chain | Key Advantage | Key Disadvantage |
|---|---|---|---|---|
Wind | Renewable | Kinetic (air) → Kinetic (turbine) → Electrical | No CO2 emissions | Output varies with wind speed |
Hydroelectric | Renewable | GPE (water) → Kinetic (turbine) → Electrical | Very reliable output | Floods large areas of land |
Geothermal | Renewable | Thermal (rock) → Kinetic (turbine) → Electrical | 24/7 year-round output | Only viable in tectonically active regions |
Solar Heating | Renewable | Light → Thermal | Low running cost for hot water | No electricity output |
Solar Cell | Renewable | Light → Electrical | No moving parts, low maintenance | High initial purchase cost |
Fossil Fuels | Non-renewable | Chemical → Thermal → Kinetic → Electrical | Low construction cost, reliable | Releases CO2 and air pollutants |
Nuclear | Non-renewable | Nuclear → Thermal → Kinetic → Electrical | Very high energy output per kg fuel | Produces long-lived radioactive waste |
7. 常见问题
学习本专题需要使用公式或进行计算吗?
不需要,该子专题仅要求对能量转移和优缺点进行定性描述,不涉及计算内容。
本专题是否属于爱德思双证书物理的考纲范围?
不属于,该内容仅属于单证书物理(4PH1)考纲的高阶试卷2,不会在4SD0双证书考试中考查。
核能属于可再生能源吗?
不属于,核能依赖总量有限的铀燃料,因此被归类为不可再生能源,尽管其运行过程中不会产生二氧化碳。
下一步
Now that you have mastered energy resources and generation chains, you are ready to move to linked advanced topics in the Edexcel IGCSE Physics syllabus. Next, you will learn how electromagnetic induction works in generators to convert kinetic energy to electricity (Section 6), and the detailed physics of nuclear fission used in nuclear power stations (Section 7). You should also practice linking your knowledge of energy efficiency and Sankey diagrams to generation methods, as extended response questions often combine multiple energy topics. Use the cheatsheet above to memorize key facts in the run-up to your Paper 2 exam.
