Globally, built areas account for 40% of greenhouse gas emissions (GHG). Three materials – concrete, steel, and aluminium – are responsible for 23% of GHG emissions, as reported by Architecture 2030. Global road networks, bridges, dams, and almost every infrastructure needs an overhaul in order to achieve a green construction industry. Governments around the world need to come together to address these challenges.
What Does ‘Green’ Mean in Construction?
Going green in construction involves using sustainable materials, efficient water and energy use, efficient waste management, and proper city planning with green spaces to support biodiversity, among other strategies.
Let us examine some concepts that are not commonly thought of to stretch our boundaries on sustainability.
Built Area Strategy
The strategy for a built area must be to achieve full energy independence and minimal dependence on the grid – one can explore blade-less wind turbines, such as the ones developed by AeroMINE Technologies, which do not harm birds and occupy only one-tenth of the space on a flat roof. They can be easily installed and are 50% more productive than solar panels.
If electricity storage is required, we do not have to rely solely on lithium-ion batteries. Scientists at Texas A&M University have discovered a 1,000% difference in the storage capacity of metal-free, water-based electrodes. Their findings were published in Nature Materials in March 2023. Organic polypeptide and wood batteries also show promise.
HomeBiogas in Israel offers anaerobic digesters that convert organic waste into biogas, providing greater self-reliance for built areas. Cambridge University in England has invented a plant-based film, a daytime radiative cooling (DRC) material that cools when exposed to sunlight and rivals air conditioning units in its cooling capacity.
Densely populated areas with a greater number of high-rise apartments can switch to washing and drying clothes in laundromats that operate on liquid CO2, which is non-toxic, biodegradable, and fully recyclable. Such machines are in existence in major US cities – currently in use by entrepreneurs who solely cater to the hospitality industry. A switch to a liquid CO2 business model can save billions of gallons of water for water-starved regions around the world. Fresh water can be harvested from the air for household use. A startup such as SOURCE uses its hydro panels to accomplish this feat.
Decentralised and self-reliant strategies enable us to achieve net-zero emissions with minimal impact on land and water and they will ultimately lower costs for the consumer due to the nonexistence of centralised production and distribution players.
Many startups are offering cost-saving solutions to built areas. SolarSkyrise in the US has capitalised on a 2023 study’s finding that 2-3% of buildings with high square footage in major US cities account for 50% of the emissions in that city. Governments may also need to create tax incentives for both startups and consumers to embrace energy-efficient solutions.
Built Area that Integrates Eastern Wisdom
Several hundreds of years ago, India discovered an ancient science of architecture called “Vastu”. Vastu aligns structures in a way that creates balance with cosmic forces/energies. The layout design suggests the right placement of the kitchen, bedrooms, bathrooms, dining and living rooms, as well as the preferred direction of sleep. Natural materials are used for construction, and the science is based on magnetic forces, the rotation of the Earth, movements of the sun, the five elements of the Earth, cosmic energies, and more. The interior and exterior designs embrace green building concepts. The seers believed that Vastu-compliant structures contribute to the well-being, happiness, and prosperity of the people who dwell in them. Similar to a good diet, exercise, and positive thinking, living or working in a Vastu-compliant building is considered equally important.
People can adopt the Vastu template for constructing a built area and then integrate into their green building concepts. Green building concepts do not explicitly proclaim to create well-being and happiness for the dweller, but Vastu does. Existing structures can borrow principles from Vastu as appropriate or feasible. The science of Vastu has immense literature on city planning, too. When integrated with clean technological innovations occurring all across the world, the wisdom from the East can usher in true global prosperity.
Green Construction: Materials Strategy
Biomimicry (or biomimetics) – a technological-oriented approach focused on putting nature’s lessons into practice – has inspired many efficient building designs, drawing inspiration from termite mounds, beetles, pine cones, lotus flowers, and more. Green concepts are evolving towards “living building materials”. The idea is that, if a coral reef can build and repair itself, we can develop materials that mimic this process.
There are many examples of how this concept was put into practice around the world. Binghamton and Rutgers University developed a self-healing concrete, where dormant fungi spores in the concrete become active when cracks occur, repairing the damage. While US-based BioMason worked on manufacturing cement and bricks using microbes and boasting the lowest carbon footprint. Mycelium bricks have been used in building construction. Another US-based company, Ecovative, creates everyday materials using mycelium, while Boston Metals produces green steel with no emissions. In Germany, Green City Solutions offers a special type of moss that absorbs pollutants from the air and cools the surrounding temperature, while Zaak Technologies upcycles waste from various industries to produce green construction materials, for example, converting fly ash from coal plants into Lypors, an alternative to sand.
New developments in bio-composites, materials science, biology, and the use of natural materials like bamboo, hemp, or flax can inspire entrepreneurs to replace the mining of metals with natural materials for both buildings and infrastructure projects.
Significant and strategic improvements are also required when we think of our road networks. We need to turn our road networks into carbon sinks and use materials from our wastewater (instead of dumping them in oceans) to recharge our dangerously low groundwater levels.
We now also have technologies that can generate electricity by harnessing the chemical differences between freshwater and seawater prior to its entry into the sea. This can be done through a special membrane separator, as scientists at Rutgers University have demonstrated. Similarly, most water desalination plants around the world are outdated, energy-intensive, expensive, and create more brine. Scientists at the University of Illinois have demonstrated that the vast amounts of water vapour above oceans can be captured by much cheaper structures in a more efficient manner.
Most countries are investing in massive infrastructure to create a hydrogen economy. However, new research by scientists at Princeton University and National Oceanic & Atmospheric Association (NOAA) challenges the notion of hydrogen as a safe alternative to fossil fuels, suggesting that a chemical reaction in the lower atmosphere could restrict the potential of hydrogen as a clean fuel as it is linked to planet-warming methane emissions.
A hydrogen economy needs specially coated steel structures and strong materials with a need for maintenance, making careful thought and consideration a requirement before massive infrastructure investments. Despite robust standards, some leakage during production and transmission may be unavoidable.
By seamlessly integrating the scientific wisdom of Vastu from ancient India with novel developments in materials science, biology, and microbiology, we can effectively reduce greenhouse gas emissions and create a more sustainable future while increasing the happiness of people living in built areas. If we think along the lines of creating a circular economy, every waste could be utilised to create infrastructure, from buildings and bridges to roads and bodies for ships, trains, or automobiles. The challenge for material scientists is to think of circularity when it comes to materials.
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