We hear this term all of the time, it’s right up there on the list of ideas that governments are pushing, so let’s look at what it means…
Officially
Renewable energy refers to energy derived from natural sources that replenish themselves over short periods of time, unlike fossil fuels which take millions of years to form and are exhausted much faster than they are replenished. The most common forms of renewable energy include solar, wind, hydroelectric, biomass, and geothermal power. These sources are considered renewable because they harness natural phenomena, such as sunlight, wind, water flow, organic plant and waste material, and the Earth’s heat, which are inherently abundant and sustainable. The term “renewable energy” implies a form of clean energy production that has a minimal long-term impact on the environment, contributing to a reduced carbon footprint and helping to mitigate the effects of climate change. By leveraging renewable energy, societies aim to shift away from carbon-intensive energy sources, thus promoting environmental sustainability and energy security for future generations.
The reality
Each form of renewable energy, despite being touted as being a cleaner alternative to fossil fuels, has some serious negative impacts on the environment:
Solar Energy:
- Habitat disruption due to large-scale solar farms.
- Resource-intensive manufacturing processes for solar panels, involving hazardous materials.
- Waste management challenges related to solar panel disposal after their lifecycle ends.
Wind Energy:
- Land use and habitat disruption for wildlife from large wind farms.
- Bird and bat mortality caused by turbine blades.
- Noise pollution and visual impact from wind turbines.
Hydroelectric Power:
- Disruption of aquatic ecosystems and fish populations.
- Methane emissions from decomposing organic matter in stagnant reservoirs.
- Potential displacement of communities and changes in land use due to reservoir creation.
Biomass Energy:
- Air pollution from burning biomass materials.
- Overharvesting of biomass resources can lead to deforestation and loss of biodiversity.
- High water usage for crop cultivation used in biomass energy production.
Geothermal Energy:
- Release of greenhouse gases like carbon dioxide and sulfur dioxide during extraction.
- Surface instability leading to subsidence or even earthquakes.
- Water usage and potential contamination of groundwater from geothermal fluids.
I want to take just one of these so called ‘renewable energies’ and explore the truth of it…
Solar panels
Solar panels are promoted as lasting for 25 years but many people are finding that they in fact last around 10 years before needing to be replaced. That’s a vast amount of material going to the landfill.
What are they made from
Solar panels are not made directly from oil, but the manufacturing process of solar panels involves materials and energy that is derived from oil. Here’s a more detailed breakdown:
- Materials:
Solar cells are primarily made from silicon, which is derived from sand. However, other components, like plastics used in the framing and backing of solar panels, can be derived from petrochemicals, which are made from oil. - Energy Use:
The manufacturing process of solar panels is energy-intensive, often involving high temperatures to refine silicon and produce the panels. The energy used in these processes can come from various sources, including fossil fuels like oil, depending on the energy mix of the manufacturing location. - Transportation:
Oil is also indirectly involved in the transportation of raw materials and finished solar panels, as vehicles and ships commonly use petroleum-based fuels.
Thus, while solar cells themselves do not contain oil, the broader lifecycle from production to deployment involves oil and other fossil fuels to varying extents.
Sand to solar cells
The formation of sand is a natural process that can take anywhere from thousands to millions of years, depending on the specific geological and environmental conditions. Sand primarily originates from the weathering and erosion of rocks, a process that breaks down large rocks into smaller particles over long periods.
The transformation of sand into solar cells is a sophisticated and multi-step process, primarily because solar cells are made from silicon, which is derived from sand. First, sand, which is primarily composed of silicon dioxide (SiO2), is purified to produce metallurgical grade silicon through a reduction process involving carbon in an electric arc furnace. This crude silicon is further refined to semiconductor-grade silicon using methods such as the Siemens process, where impurities are removed to achieve high purity. The purified silicon is then melted and crystallised into ingots or boules, which are subsequently sawed into thin wafers. These wafers are doped with other elements to create positive and negative layers necessary for creating an electric field. Finally, the wafers are treated and assembled into cells, coated with anti-reflective materials, and encapsulated into solar panels ready for energy production. Each step is crucial in ensuring the efficiency and effectiveness of the solar cells in converting sunlight into electricity.
Aluminium
Aluminium is favoured for solar panel frames, due to its lightweight, strong, and corrosion-resistant properties, making it ideal for outdoor use. Although recyclable, aluminium often ends up in land fills because of the costs of recycling it.
Aluminium is sourced primarily from bauxite ore, which is the most common material used in aluminium production. Here’s an overview of how aluminium is produced from bauxite:
Mining:
Bauxite is mined from the earth, primarily in countries like Australia, China, Brazil, and India.
Refining:
The bauxite is then refined to produce alumina (aluminium oxide) through a process known as the Bayer process. In this method, bauxite is treated with sodium hydroxide solution, which dissolves the alumina. The resulting solution is then precipitated out, leaving behind impurities.
Smelting:
The alumina undergoes an electrolytic process called the Hall-Héroult process to extract pure aluminium metal. This process involves dissolving alumina in molten cryolite and passing an electric current through it, which reduces the alumina to aluminium metal.
Manufacturing:
The pure aluminium produced is then cast into ingots, sheets, or other forms, and can be further processed into various products, including the frames for solar panels.
The formation of bauxite ore is a geological process that generally takes millions of years. Bauxite is primarily formed in tropical and subtropical regions where climatic conditions are conducive to the intense weathering of underlying rock.
Plastics
Solar panels incorporate plastics, but the amount varies depending on the type and design of the panel. Typically, plastics are used in the encapsulation layer and the backsheet of the panel. The encapsulation layer, usually made from ethylene-vinyl acetate (EVA), seals in the solar cells to protect them from environmental factors like moisture and dirt, while providing insulation. The backsheet, which is often made from polyvinyl fluoride (PVF) or polyethylene terephthalate (PET), serves as the protective outermost layer on the underside of the panel. These plastic components are crucial for the durability and efficiency of solar panels, ensuring that they can withstand various weather conditions and maintain performance over time. Plastics are essential for these functions.
Solar cabling, which is essential for connecting solar panels to each other and to the power system, significantly utilises plastic for insulation and protection. The cables are typically insulated with materials like polyvinyl chloride (PVC) or cross-linked polyethylene (XLPE), both of which are forms of plastic. These materials are chosen for their electrical insulation properties, resistance to heat, durability, and ability to withstand environmental exposure. The plastic insulation is critical in preventing electrical leaks, resisting corrosion from exposure to sunlight, water, and chemicals, and providing overall mechanical protection for the conductive materials inside. While the exact amount of plastic used can vary depending on the cable specifications and the scale of the solar installation, plastic generally constitutes a substantial portion of the composition of solar cabling, ensuring both safety and longevity in solar energy systems.
Plastics are derived from oil by refining petroleum to create petrochemicals, which are then polymerised to form various types of plastics.
Conclusion
Solar panels are not a renewable resource, as they are manufactured using finite materials that require mining and processing, such as silicon (derived from sand), metals like silver and aluminium, and various synthetic materials. These resources are limited and subject to depletion. Additionally, the production process for solar panels is energy-intensive and involves emissions, which can have huge environmental impacts.
The production of CO2 during the manufacture of solar panels is a significant concern due to this energy-intensive nature of the processes involved. Extracting and purifying silicon, which is the primary material in most solar cells, requires substantial amounts of energy, which is sourced from fossil fuels, including oil. Additionally, the production and transportation of other panel components relies on oil, either directly as a raw material for plastics and other synthetic compounds or indirectly as the primary fuel for transportation and machinery. This dependency on fossil fuels results in considerable CO2 emissions, which negates the original intention of the application of large scale solar.
The push for solar farms and photovoltaic power stations has a political motivation that doesn’t appear to have science or common sense to back it up.