It is often spoken of the grey energy to show that the environmental impact of a product or material is not limited to its visible components. This hidden impact is represented by grey energy, or «embodied energy» in English, which designates the amount of energy used throughout the entire life cycle of the product, from the extraction of raw materials to their final disposal or recycling. Although not obvious to the end consumer, the impact of this energy is very significant, especially in industrial processes.
What is grey energy?
La grey energy It is all the energy involved in the production, Services, transformation y use of a product or material. This concept includes everything from the energy needed to extract raw materials to the energy used in recycling or final disposal of the product. It is commonly included in product life cycle analysis to measure the environmental impact global, and is key to understanding the true energy cost of the products we consume.
Levels of gray energy
Gray energy can be considered at several levels:
- La manufacturing of the material or product.
- La extraction of raw materials.
- El Services of these raw materials to the production or assembly plants.
- La transformation of raw materials into finished products.
- La merchandising and distribution of said products.
- El use or the use of the product throughout its useful life.
- El recycling or the final disposition of the product.
Differences between renewable and non-renewable grey energy
The concept of grey energy can be broken down into two categories, depending on whether it comes from renewable or non-renewable sources. non-renewable grey energy refers to processed energy that comes from fossil fuels or other non-renewable sources, while renewable grey energy comes from energy sources such as solar, wind or hydroelectric. In many cases, the difference between the two is crucial to assessing the environmental impact of a product, since the use of non-renewable grey energy contributes directly to greenhouse gas emissions.
The impact of grey energy on buildings
One of the sectors where the concept of grey energy is most used is in the constructionIn fact, it is increasingly being seen how buildings can be large consumers of grey energy before they even begin to operate. The extraction of raw materials such as cement and steel, and their subsequent transport, as well as the construction of the building, require an enormous amount of energy. It is estimated that in some buildings, the use of grey energy can represent up to 30% of the total consumption of the property over a period of 50 years.
Grey energy in buildings is not limited to the construction phase; it also includes energy used in maintenance, repair and renovation throughout their lifespan. Furthermore, when it comes time for demolition, the energy required to dismantle and manage construction waste is also part of a building’s grey energy load. This highlights the importance of selecting materials with lower grey energy and designing buildings that use fewer resources over their lifetime.
How to reduce grey energy?
To reduce the grey energy impact of products and buildings, there are several key strategies that can be implemented:
- Use recycled materials: Choosing materials that have already been recycled reduces the amount of energy required for the extraction and processing of raw materials.
- Optimize layout: Designing buildings and products that use less materials or have greater durability can significantly reduce associated grey energy.
- Promote the use of renewable energy: To the extent possible, factories and production plants should opt to use renewable energy sources when manufacturing products.
- Efficient transport: Choose sources of raw materials close to production centers and minimize unnecessary transportation.
Grey energy and energy efficiency in products
An interesting aspect of grey energy is that it often exceeds in impact the energy a product consumes during use. This is especially visible in the Electronic products and household appliances. In Europe, household appliances consume on average twice as much grey energy as direct energy over their lifetime. A prime example is modern cars, which, while reducing fuel consumption, require a large amount of grey energy to manufacture the advanced technological systems they incorporate, such as GPS and on-board computers. Therefore, any energy conservation strategy Energy Efficiency must take into account the complete balance of the gray energy involved.
Is it possible to calculate all gray energy?
Although there are tools and methodologies to calculate grey energy, making an accurate calculation can be very complex due to the globalization of supply chains. A seemingly simple product may have components manufactured in different countries, each with its own energy consumption. For example, a smartphone It is made up of hundreds of parts and materials, whose raw materials have been extracted in different parts of the world, processed in different plants, and then assembled and distributed from another location. This process involves an enormous amount of transport and, therefore, grey energy.
Despite the difficulty of calculating each component of grey energy, there are databases such as Ecoinvent which allow us to have a general idea of the energy footprint that certain products or services may have.
Ultimately, taking grey energy into account in our daily consumption is crucial to moving towards a more sustainable future. By making informed choices and opting for products that require less grey energy or are recyclable, we can reduce our environmental impact and contribute to global energy savings. Giving priority to local products, reusing materials and investing in energy efficiency in all production phases are essential in this task.