📚 Energy Resources | 能源资源
Energy is essential for all forms of life and for modern civilisation. We use energy for heating, lighting, transport, and manufacturing. Understanding the different energy resources available on Earth is a core topic in the Edexcel IGCSE Science course.
能源是一切生命和现代文明的基础。我们利用能源进行采暖、照明、交通和制造。了解地球上可用的不同能源资源是 Edexcel IGCSE 科学课程的核心主题。
1. What Are Energy Resources? | 什么是能源资源
Energy resources are natural or human-made sources from which useful energy can be extracted. They can be chemical, nuclear, thermal, or kinetic stores. Examples include coal, oil, natural gas, uranium, sunlight, wind, waves, and geothermal heat.
能源资源是能够从中提取有用能量的天然或人造来源。它们可以是化学、核能、热能或动能储存。例如煤炭、石油、天然气、铀、阳光、风、波浪和地热。
In IGCSE Science, we classify energy resources as either renewable or non-renewable. This classification affects their availability, environmental impact, and long-term sustainability.
在 IGCSE 科学中，我们将能源资源分为可再生和不可再生两类。这种分类会影响它们的可用性、环境影响和长期可持续性。
2. Renewable vs Non-Renewable | 可再生与不可再生
A renewable energy resource is one that can be replaced at the same rate as it is consumed, or that is effectively infinite. Non-renewable resources exist in finite amounts and will eventually run out.
可再生能源资源是指其消耗速度与补充速度相当，或实际上是无限的资源。不可再生资源储量有限，最终会耗尽。
| Renewable 可再生 | Non-renewable 不可再生 |
| Solar, wind, water, geothermal, biomass | Coal, oil, natural gas, nuclear fuels |
| Unlimited supply | Finite and depleting |
| Often lower carbon dioxide emissions | Usually release CO₂ when burned |
Renewable sources are often cleaner but may be less reliable because they depend on weather or geography. Non-renewable sources provide steady, high energy output but cause pollution and contribute to global warming.
可再生能源通常更清洁，但可能不太可靠，因为它们依赖天气或地理条件。不可再生能源提供稳定、高能量的输出，但会造成污染并导致全球变暖。
3. Fossil Fuels | 化石燃料
Coal, oil, and natural gas are fossil fuels. They formed from the remains of ancient plants and animals over millions of years under high pressure and temperature. When burned, they release energy stored in chemical bonds.
煤炭、石油和天然气是化石燃料。它们由古代动植物遗骸在高压高温下经过数百万年形成。燃烧时，释放储存在化学键中的能量。
Electricity from fossil fuels is generated by burning the fuel to heat water, producing steam that turns a turbine, which drives a generator. This process is about 30-40% efficient, and large amounts of waste heat are produced.
利用化石燃料发电时，先燃烧燃料加热水，产生蒸汽驱动涡轮机，涡轮机带动发电机。该过程中的能量转换效率约为 30-40%，并产生大量废热。
Chemical energy → Heat energy → Kinetic energy → Electrical energy
Fossil fuels release carbon dioxide, sulphur dioxide, and nitrogen oxides when burned. These gases cause air pollution, acid rain, and climate change.
化石燃料燃烧时会释放二氧化碳、二氧化硫和氮氧化物。这些气体导致空气污染、酸雨和气候变化。
4. Nuclear Energy | 核能
Nuclear energy is released when the nucleus of an atom splits (fission) or two nuclei combine (fusion). In current power stations, only nuclear fission is used. The most common fuel is uranium-235.
核能是在原子核分裂（裂变）或两个原子核结合（聚变）时释放的能量。当前核电站只使用核裂变。最常见的燃料是铀-235。
In a nuclear reactor, a neutron strikes a uranium nucleus, causing it to split into smaller nuclei and release more neutrons, which cause a chain reaction. The kinetic energy of the fragments is converted into heat.
在核反应堆中，一个中子撞击铀核，使其分裂成较小核并释放更多中子，从而引发链式反应。碎片的动能转化为热能。
²³⁵U + ¹n → ¹⁴¹Ba + ⁹²Kr + 3¹n + Energy
Nuclear power produces no carbon dioxide during operation. However, it produces radioactive waste, which remains dangerous for thousands of years and must be stored safely. There is also the risk of accidents.
核电在运行期间不产生二氧化碳。然而，它会产生放射性废物，这些废物在数千年内仍然危险，必须安全储存。此外还存在事故风险。
5. Solar Energy | 太阳能
Solar energy comes directly from the Sun. Photovoltaic cells convert light into electricity, while solar panels absorb heat for water warming or space heating. Solar energy is renewable and available almost everywhere.
太阳能直接来自太阳。光伏电池将光能转换为电能，而太阳能集热板吸收热量来加热水或空间。太阳能是可再生的，几乎处处可用。
Solar power is clean and quiet, but it is intermittent: at night and on cloudy days, output is low. Large areas of panels are needed for high output, and the initial cost is significant.
太阳能清洁且安静，但它是间歇性的：夜间和阴天输出较低。高输出需要大面积的电池板，初始成本较高。
The efficiency of a solar cell is given by:
Efficiency = (Electrical power output / Light power input) × 100%
Typical commercial solar cells have efficiencies between 15% and 20%. Advances in technology are gradually improving this value.
典型的商用太阳能电池效率在 15% 到 20% 之间。技术的进步正在逐步提高这一数值。
6. Wind Energy | 风能
Wind turbines convert the kinetic energy of moving air into electricity. Large blades rotate a shaft connected to a generator. A single modern turbine can power hundreds of homes.
风力涡轮机将流动空气的动能转化为电能。大型叶片旋转轴并与发电机相连。一台现代涡轮机可为数百户家庭供电。
Wind is clean and renewable, but it is not constant. Wind speed varies with weather and location, so wind power is unreliable as a sole energy source. Turbines are also noisy and can affect wildlife.
风能清洁可再生，但并非始终恒定。风速随天气和地点而变化，因此风力发电作为唯一能源时不可靠。涡轮机还会产生噪音并影响野生动物。
To generate useful electricity, the wind speed must exceed the 'cut-in' speed. The power produced increases with the cube of wind speed:
Power ∝ (Wind speed)³
This means a small increase in wind speed causes a large increase in power, so location is critical.
这意味着风速的微小增加会导致功率的大幅增加，因此选址至关重要。
7. Hydroelectric Power | 水力发电
Hydroelectric power uses the gravitational potential energy of water stored in a high reservoir. Water flows down and spins turbines to generate electricity. It is a renewable and highly controllable source.
水力发电利用高处水库中水的重力势能。水流下并旋转涡轮机发电。它是一种可再生且高度可控的能源。
Pumped storage can be used to 'store' energy: when demand is low, excess electricity pumps water back up to the reservoir. When demand is high, the water is released.
抽水蓄能可用于‘储存’能量：当需求低时，多余的电将水泵回水库。当需求高时，水被释放。
Hydroelectric schemes produce no direct carbon dioxide, but building large dams can flood habitats and alter river ecosystems. They also depend on rainfall patterns.
水力发电计划不直接产生二氧化碳，但修建大型水坝会淹没栖息地并改变河流生态系统。它们还依赖降雨模式。
8. Geothermal Energy | 地热能
Geothermal energy uses heat from within the Earth. Radioactive decay in rocks and residual heat from formation make the ground hotter with depth. This heat can be used directly to heat buildings or to generate electricity.
地热能利用地球内部的热量。岩石中的放射性衰变和形成时的余热使地下的温度随深度升高。这种热量可直接用于建筑物供暖或发电。
In volcanic areas, hot water or steam can be extracted from boreholes to drive turbines. In colder regions, ground source heat pumps use shallow heat to warm homes.
在火山地区，可通过钻孔提取热水或蒸汽来驱动涡轮机。在较冷地区，地源热泵利用浅层热量为房屋供暖。
Geothermal energy is reliable and low-carbon, but it is only economically viable in areas with suitable geology. Drilling deep wells is expensive.
地热能可靠且低碳，但只有在具有合适地质条件的地区才经济可行。钻探深井成本高昂。
9. Biomass | 生物质能
Biomass is renewable energy from organic materials such as wood, crop waste, animal manure, and energy crops. When burned or fermented, it releases stored chemical energy from photosynthesis.
生物质能是来自有机材料（如木材、农作物废料、动物粪便和能源作物）的可再生能源。在燃烧或发酵时，它会释放光合作用储存的化学能。
Biomass can be burned directly to produce heat, or converted into biogas (methane) which fuels generators. It is considered carbon-neutral if the plants re-grow at the same rate they are harvested.
生物质可以直接燃烧产生热量，或转化为沼气（甲烷）來驱动发电机。如果植物的再生长速度与收获速度相同，则被认为是碳中性的。
However, burning biomass still releases smoke and particulates that cause local air pollution. Large-scale biofuel plantations may compete with food production for land.
然而，燃烧生物质仍会释放烟尘和颗粒物，造成局部空气污染。大规模生物燃料种植园可能会与粮食生产争夺土地。
10. Environmental Impact | 环境影响
Each energy resource has environmental consequences. Burning fossil fuels releases greenhouse gases that trap heat, leading to climate change. Sulphur dioxide causes acid rain, which damages buildings and ecosystems.
每种能源资源都有环境影响。燃烧化石燃料释放温室气体，捕获热量，导致气候变化。二氧化硫导致酸雨，破坏建筑物和生态系统。
Nuclear power produces radioactive waste that requires secure long-term storage, and a major accident could contaminate a large area. Hydroelectric dams alter aquatic habitats and emit methane from flooded vegetation.
核电产生需要安全长期储存的放射性废物，重大事故可能污染大片区域。水坝改变水生栖息地，淹没植被释放甲烷。
Renewable sources like solar and wind reduce greenhouse gas emissions but may require large land areas or affect local wildlife. The choice of energy resource involves balancing environmental, economic, and social factors.
太阳能和风能等可再生能源减少了温室气体排放，但可能需要大面积土地或影响当地野生动物。能源资源的选择需要平衡环境、经济和社会因素。
11. Efficiency and Cost | 效率与成本
Efficiency measures how much useful energy is transferred from the total energy input. It is calculated as:
效率衡量从总能量输入中转移出多少有用能量。其计算公式为：
Efficiency = (Useful energy output / Total energy input) × 100%
For example, if an old coal station transfers 30 J of electrical energy from 100 J of chemical energy, its efficiency is 30%. Modern gas turbines can reach over 60% efficiency.
例如，如果一座旧煤电站从 100 J 化学能中转移出 30 J 电能，其效率为 30%。现代燃气轮机可达到 60% 以上的效率。
- Fossil fuels: low fuel cost, high extraction cost, widely used.
- Nuclear: high construction cost, low fuel cost, expensive waste management.
- Solar/wind: low running cost, high initial installation cost, intermittent.
- 化石燃料：燃料成本低，开采成本高，使用广泛。
- 核电：建造成本高，燃料成本低，废物管理昂贵。
- 太阳能/风能：运行成本低，初始安装成本高，具有间歇性。
Governments use 'levelised cost' to compare power sources, counting building, operation, fuel, and decommissioning over a plant's lifetime.
政府使用‘平准化成本’比较不同电源，涵盖建设、运行、燃料和退役等全生命周期的费用。
12. Choosing the Best Resource | 选择最优资源
There is no single 'best' energy resource. The choice depends on location, climate, technology, cost, and public acceptance. A country may use a mix of resources to ensure security of supply.
没有单一的‘最佳’能源资源。选择取决于地理位置、气候、技术、成本和公众接受度。一个国家可能使用多种资源组合来确保供应安全。
For instance, Iceland uses abundant geothermal and hydroelectric energy, while many desert regions are ideal for solar power. Island nations often rely heavily on wind and tidal energy.
例如，冰岛利用丰富的地热和水力能源，而许多沙漠地区非常适合太阳能发电。岛国通常严重依赖风能和潮汐能。
Sustainable energy planning considers the carbon footprint, renewability, environmental damage, and ability to meet future demand. As technology improves, renewables are becoming cheaper and more reliable.
可持续能源规划考虑碳足迹、可再生性、环境破坏以及满足未来需求的能力。随着技术进步，可再生能源正变得更便宜、更可靠。
In the IGCSE exam, you should be able to compare resources using data, explain energy transfers, and discuss advantages and disadvantages clearly using the terms renewable, reliable, and environmentally friendly.
在 IGCSE 考试中，你应能使用数据比较各种资源，解释能量转换，并清楚讨论其优缺点，使用可再生、可靠和环保等术语。
Published by TutorHao | Science Revision Series | aleveler.com
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