Non-renewable energy resources currently dominate the market, but there is a growing interest in renewable energy as Earth's population continues to grow. Pollution from traditional energy sources is driving the change in demand.
Solar energy for example is one of the most promising renewable resources, as it is abundant and does not produce greenhouse gases. Additionally, research is ongoing in order to make solar panels more efficient and cheaper to produce. While Earth's energy landscape is changing, it is clear that both renewable and non-renewable resources will play a role in meeting the needs of our growing population.
The planet provides a multitude of energy resources. Let us have a look at a few of them below.
- This article is an introduction to energy resources.
- First, we'll define what energy resources are.
- Then, we’ll learn about the sources of energy resources.
- we’ll continue with the importance of energy resources.
- We’ll finish with some examples of energy resources.
Energy Resources: Definition
Energy resources can be defined as materials or elements that can be used to produce energy. Energy is a quantitative property, which produces an output or a force that can be analysed.
This energy can be in the form of electricity, heat, or mechanical energy.
Three primary types of energy include fossil fuels, nuclear energy and renewable energy, each type of energy resource with its own advantages and disadvantages.
Main Sources of Energy Resources
In order to assess their qualities better, Earth's main sources of energy resources can be divided into two categories, namely, renewable and non-renewable.
Non-renewable resources, such as fossil fuels, are exhaustible and cannot be replaced once they have been used up. Or taking millions of years to form again e.g. fossil fuels, uranium & plutonium, etc.
Renewable resources, on the other hand, are replenishable and include sources like solar, wind, and hydro.
Energy can be renewable but not necessarily sustainable at the same time, e.g. river water saturated with biodiversity markers when combined with hydro-power dam systems along its course, non-regenerative tree plantations, etc.
Having a look at the good and the ugly of energy resources tells us quite a bit about our natural environment.
| Source of energy resources | Advantages / Disadvantages | Explanation |
| Renewable | Advantages | - Reliable
- Non-exhaustible
- Less pollutive (little or no particulate matter or chemical pollution generation, depending on type)
- Less maintenance costs
- Increases public health and wellbeing standards
|
| Disadvantages | - Intermittent or seasonal
- Lower efficiency
- Higher initial costs
|
| Non-renewable | Advantages | - High energy output
- Easy to produce and use
- Abundance and affordability
|
| Disadvantages | - Decreased public health and wellbeing standards
- Chemical and particulate matter pollution
- Exhaustible
- Non-recyclable and hard to dispose of residues and by-products
|
Table 1: Some advantages and disadvantages of renewable and non-renewable energy, the main types of source for energy resources.
Fossil fuels are a readily available energy source but their combustion emits greenhouse gases that contribute to climate change. Nuclear energy is a very efficient energy source but it produces radioactive waste that can be difficult to dispose of safely. Renewable energy sources, such as solar and wind power, are sustainable but they can be intermittent and may require storage systems to even out supply and demand. Energy resources are essential for powering our homes, businesses, and industries but it is important to consider the pros and cons of each type of resource.
Specific Sources of Energy Resources
Now, let's see some of the specific sources of energy resources.
Fossil fuel: dead organic matter, mostly composed of bacteria, algae and plants, subjected to high heat and pressure over millions of years. Most of the reserves we have today were formed during the Carboniferous-Permian geological periods of Earth.
"Elemental": usually present as major replenishable components of Earth's abiotic spheres.
Nuclear: atoms interacting to produce vast quantities of energy
Biomass: plants, algae, bacteria, animals, etc.
These energy sources may further create vectors or may be delivered through energy vectors.
Vectors: humans create energy vectors from primary energy sources. Electricity and hydrogen are good examples as they mostly exist in nature in weak or non-constant forms. Humans can create a steady flow of electric currents of different voltages for various applications. Similarly, hydrogen as a stand-alone gas constitutes only 0.00005% of the atmosphere and may otherwise be found bound to oxygen molecules, in coal, petroleum, etc. Humans isolate hydrogen through a number of processes and use it as energy fuel.
Importance of Energy Resources
The importance of energy resources is obvious because society wouldn't be able to function without them. Sectors that greatly benefit from constant energy availability are:
- Heavy industries: melting, lifting, lighting, computers, etc.
- Agriculture & fisheries: water filtration and irrigation, tilling and harvesting machinery, etc.
- Domestic Life: gas and electricity for heating, cooking, cleaning, etc.
- Fuels: transport: gasoline, distillate fuels, biodiesel, etc.
- Healthcare: ventilation, equipment usage, etc.
Fig. 1: Sources of global energy consumption from the 1800s until the present day. The spike in energy consumption coincides with the spike in greenhouse gases detected in the atmosphere.
Improving Energy Resources
A number of factors can contribute to an increase in global energy supplies, such as the development of new sources of energy, the efficient use of existing resources, and the implementation of policies that encourage conservation.
The world's population is projected to grow to 9.7 billion by 2050, which will lead to increased demand for energy. It is essential that we develop a mix of energy sources in order to meet the world's growing needs.
Perhaps in all cases, conserving the quality of the soils and habitats, and encouraging technological advancement, help ensure humanity will be able to improve their access to and choices of sustainable energy resources. Below we will see a few examples.
Highly Calorific Biomass (measured in kcal/kg and also known as "high energy-density"): biomass used for cooking and heating purposes, including dry peat and wood chips made from deciduous trees.
Protection and improvement of biomass resources includes:
- Allowing peat areas to regenerate
- Recycling used materials with a high cellulosic content like coffee grounds and filter papers
- Planting mixes of deciduous trees
- Reusing agricultural biomass like wheat, barley and rice straw, corn husks and cobs
- Maintaining healthy genes and soils for plants to grow
- Lignocellulosic materials may be prioritised in already existing plantations, e.g. sugarcane.
Water resources: the total water resources available on Earth in all its forms, including gaseous and solid. Protection and improvement of water resources includes:
- Using drip irrigation instead of sprinklers
- Capturing atmospheric water (e.g. Atmospheric Water Generators "AWGs", fog collectors in the form of sails, etc.)
- Rainwater collector tanks
- Water desalinisation and reverse osmosis plants
- Water purification devices
- Diverting pollution away or capturing it from freshwater reserves.
Question: What other improvements can you think of that can help with climate change and energy efficiency?
Answer: Building energy improvements, ranging from wall and roof insulation using natural thermally-efficient materials such as fibres, cob, animal waste and straw; double or triple glazing; "passivhaus" designs; natural building materials like limecrete.
A type of Bacteria-based self-healing concrete has been created and is currently being researched for large-scale deployment. It is infused with tiny pockets or capsules of carbonate-producing bacteria and their preferred nutrients. They start to grow and multiply in the presence of water, should it permeate through concrete cracks. These bacteria then produce limestone from consuming the nutrients as they grow, effectively sealing the cracks in which they grow.
"Passivhaus": German word meaning "passive house". The goal of passivhaus design is to create a highly energy-efficient building that requires little to no active heating or cooling systems. Efficient designs will include anything, from Bedouin tents ensuring natural ventilation and cooling, to stone churches.
Energy Resources and Climate Change
Using energy and especially fossil fuels for electricity creates greenhouse gas emissions. Each greenhouse gas has a unique global warming potential (GWP) due to being able to absorb and trap infrared radiation (IR).
The building materials, commissioning and decommissioning stages of any energy-producing technology will emit various greenhouse gases.
These stages include smelting and transportation, soil water draining, land use, etc.
For calculation efficiency purposes, the three major GHG emissions from human activities have been summed into the value CO2e or CO2eq (both meaning "carbon dioxide equivalent").. CO2e incorporates (at least) the CO2, N2O (nitrous oxide) and CH4 (methane) that are frequently emitted at the same time from the combustion of fossil fuels and related activities. CO2e figures are therefore more accurate in predicting environmental damage when compared to carbon dioxide emissions alone. Certain energy-production processes may emit different greenhouse gases from the ones mentioned.
Coal-burning also emits SO2 (sulfur dioxide) which is considered an indirect GHG. It has both cooling and warming potential. SO2 also participates in the formation of aerosols with GHG impact. Carbon reacts with sulfur creating carbon disulfide (CS2) and carbon dioxide. Erupting volcanoes also emit large quantities of water-soluble SO2, which typically fall down on earth as acid rain. It also contributes to ground-level ozone (O3) formation.
Challenges include intermittence, distribution, access, and level of risk to human or environmental health.
Human society is currently dependent on non-renewable energy resources. As of 2021, 80% of the world's energy is supplied by fossil fuels, which, when consumed at this rate and without strong anti-pollution measures, are unsustainable.
Energy Resources Examples
We summarize in the table below the main characteristics for key energy resources:
| Key resource | Specifications |
| Coal | - Source of electrical and heat energy.
- Can be gasified and liquified.
- Used as chemical source for synthetic compounds like dyes, pharmaceuticals, etc.
|
| Wind | - Mechanical power (grain grinding, water extraction, propelling ships)
- Electricity generation (wind turbines)
|
| Gas | - Propelling
- Heating
- Electricity
- Synthetic compounds (eg. paints)
|
| Geothermal | - Heating and cooling for various purposes (greenhouse maintenance, food dehydration, etc.)
|
| Solar | |
| Nuclear | - Main elements used: uranium, plutonium, hydrogen, thorium
- Fission: Sizewell nuclear power stations, Suffolk, UK
- Fusion: Tokamak reactor, Saint-Paul-lès-Durance, France
- Ups: sustainable, high energy yield
- Downs: non-renewable, high risk
|
| Wave | - Electricity generation
- Mechanical uses (pumping water, etc.)
|
| Hydroelectric | |
| Oil | - Propelling
- Heating
- Electricity
- Chemical compounds (e.g. pharmaceuticals)
|
| Biofuel | - Propelling
- Heating
- Electricity
|
| Tidal | |
| Green Hydrogen | - Electricity generation
- Power
- Heat
|
Table 2: Main characteristics for key energy resources.
Energy Resources - Key takeaways
- The Earth's main energy sources can be divided into renewable and non-renewable.
- Just because something is renewable, it doesn't mean it's also sustainable. Similarly, non-renewable resources can be used at a sustainable rate.
- Energy is usually electric, heat, or mechanical.
- Humankind is still heavily dependent on fossil fuels (around 80% of all energy supplied).
- The use of all energy sources like coal, wind, oil, solar, tidal, nuclear, etc. needs to take into account the biota and abiota on Earth to ensure the continuation of species.
References
- World Data, Energy mix, 2021. Accessed 12.06.22
- Sasan Saadat & Sara Gersen, Reclaiming Hydrogen for a Renewable Future, 2021. Accessed 12.06.22
- Fig. 1: Hannah Ritchie, Max Roser and Pablo Rosado (2022) - "Energy". Published online at OurWorldInData.org. Retrieved from: 'https://ourworldindata.org/energy' [Online Resource].
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