ENVIRONMENTAL IMPACT
it,” says Caitlin Wale, founder of the African climate tech accelerator Kinjani. “We have the potential to grow green from the start.” Her enterprise is raising capital to “capture the massive climate opportunity” and help companies with access to much-needed funds. One starting point are construction materials: Cutting-edge technologies and processes needed to green the building sector, such as the production of lower-carbon cement, have often been developed in advanced economies. As imports are expensive and not necessarily the best option for local markets, architects in Nigeria “rediscovered” local materials like red clay bricks which are more suited to the country’s climate as well as being more weather resilient. In other cases, as a substitute for cement in concrete, scientists developed ways to use mining waste and biochar, which is produced from heating biomass. The OPEC Fund is supporting a project to provide affordable and sustainable housing in the Sahel region in Africa which is based on ancient techniques and traditional expertise. The so-called Nubian vault, named after the region’s ethnic group from the Nile Valley, is an environmentally friendly and sustainable way of using pure earth to build roofs and ceilings without the need for timber (see page 22). Another example comes from India where low-cost materials are used instead of bricks and mortar to bring down the price of housing and speed up the building process. The Indian government is constructing thousands of homes using glass fiber reinforced gypsum to create a strong yet lightweight panel which can be used for walls, floors and roofs. The reduced need for cement and steel not only makes such homes up to 30 percent cheaper, it also significantly lowers their carbon footprint. India, according to the World Economic Forum, has a shortage of 34 million housing units. The situation is even more pressing in Africa: “The housing deficit in Africa is estimated at over 97 million units and this is expected to increase as the continent’s population grows, and urbanization continues,” reports the International Finance Corporation (IFC), the World Bank’s private sector arm. New technology is playing an
a fraction of the time a traditionally-built school would take. Co-financed by IFC “the project will demonstrate the viability of the sector to local developers,” the World Bank subsidiary said. But building new homes alone will not be enough. Estimates show that two- thirds of the buildings that exist today will still be around in 2050 – “presenting both structural and environmental problems,” as the World Bank says in a recent paper. The good news is that technology is already available to address these issues: 3D scans are mapping informal settlements, while machine learning software is being used to efficiently and cheaply identify buildings at risk of collapse. Newer technologies such as light- reflecting paint and low-cost structural retrofit techniques can go a long way toward making homes safer and greener. Augmenting these technologies, many experts believe digitalization will be the big gamechanger. Across all project stages, digitalization could increase materials’ efficiency by integrating life-cycle emissions, using 3D building information modeling, enhancing collaboration in the construction process through management apps on mobile devices and monitoring sites with drones for scanning. Paper-based work practices, cost increases and technological illiteracy are, however, likely to represent key barriers in developing countries, especially in low-income and fragile countries as well as middle-income economies with construction sectors featuring a large presence of informal and small construction companies. Internet-connected appliances can help reduce energy consumption by enabling the use of dynamic electric pricing and time-of-use tariffs. These smart appliances, along with energy efficient management retrofit systems, can reduce energy consumption by 20 to 30 percent. The Super-Efficient Equipment and Appliance Deployment Initiative, led by the International Energy Agency, for instance, provides support to more than 20 governments to implement energy efficient policies for appliances and equipment and identify and promote the adoption of innovative smart devices and systems.
A family home built by 14Trees
increased role in addressing this gap: In 3D-printed homes, the primary structural components like walls and foundations are constructed using industrial-sized 3D printers which follow a digital template to “print” the property layer-by-layer using cement, concrete and other building materials. After the 3D printing of the core structure, builders add other parts like the windows, plumbing and electrical wiring through traditional construction methods. The main benefits of 3D-printed homes are reduced construction time – “printing” the foundations and walls can take a day or two instead of several weeks – and lower costs as the properties are estimated to be at least 20 percent cheaper than traditionally built homes. In Africa, a joint venture involving the UK development finance institution CDC Group and the multinational building materials manufacturer Holcim is 3D-printing houses and schools in a fraction of the time it would normally take to construct them. Called 14Trees, it has operations in Malawi and Kenya and is able to build a 3D-printed house in just 12 hours at a cost of under US$10,000. Its building process reduces CO2 emissions by as much as 70 percent when compared with a typical house-building project. The company’s first-ever affordable, 3D-printed home was built in Lilongwe, the capital city of Malawi. 14Trees has also recently completed its first 3D-printed school, also in Malawi, built in
12
Powered by FlippingBook