Green technology for sustainable world

From Bangladesh’s perspective

13 December, 2020 12:00 AM printer

Without green technology, it would be impossible to think of a sustainable world or future mankind. Social equitability, economic feasibility and environmental sustainability are the key parameters for green technologies. Especially in developing countries which mainly focus on how these technologies worked to conserve nature and how they are benefited.

In the past few years, Bangladesh has been going through a digital revolution. Its economy is growing at 7 per cent, and soon we'll be citizens of a middle-income country. However, as old industries like readymade garments and fisheries grow and new industries like ICT emerge, one big concern remains: how do we balance high economic and technological growth with environmental sustainability.

Cityscape Tower is considered a cultural and business hub of Dhaka city, and while most of us have probably been there just to get coffee, this building is one of the pioneering structures that promote green architecture in the country. The building has a self-sustaining power and water supply. This ensures 40 per cent less power consumption and reduces water wastage by 60 per cent. Green architecture heavily depends on generating renewable energy and recycling.

As the industries of Bangladesh continue to thrive and its population grows, the natural environment and climate of the country will continue to deteriorate unless proper steps are taken. Industries should adopt green technologies, while citizens should adopt a green lifestyle. If we all play our parts right, our economic growth will continue to be strong and sustainable. Green technology is all encompassing. It deals with using science and technology in order to protect the environment. A lot of techniques fall under this term such as the use of green chemistry, environmental monitoring, and more. All of these things have to deal with making sure that the environment remains protected. This technology is used to breathe life back into a damaged ecosystem. It is also referred to as environmental technology or clean technology. The main goal is to conserve nature, and to remedy the negative impact that humans have on it.

Here are few step for creating a green world:

1.    Wastewater treatment

                In this field, there are few technological developments, but the existing ones are important. Key developments include membrane filtration, microbial fuel cells, nanotechnology, development of biological treatments and natural treatment systems such as wetlands. All these processes are used to make water drinkable or significantly reduce the presence of pollutants from what is discharged into the sea and rivers.

   2.  Elimination of industrial emissions

                As experts in the treatment of emissions, the management of air pollutants in industries can significantly reduce the greenhouse effect. Methane and carbon dioxide are substances that harm the environment. Industries such as chemical, petrochemical, pharmaceutical, automotive, etc. must eliminate their emissions so as not to cause serious environmental damage. Our technology is oriented to create custom solutions for each company.

3. Recycling and waste management

                The increase in household and industrial waste has been disproportionate. Managing solid waste is the commitment of companies as well as individuals. Outstanding technologies such as smart containers, automated food waste tracking systems and automated optical scanning technologies can help sort mixed plastics by separating them from others.

   4. Self-sufficient buildings

                Self-sufficient buildings are those constructions that are able to function by themselves by generating energy without the need of an external contribution. One way to achieve greater production with the same surface of photovoltaic panels is to incorporate intelligent solar tracking systems, thus obtaining an optimal use of radiation.

   5. Waste-to-Energy

                The generation of energy from waste, also called Waste-to-Energy, is technology that generates energy from garbage. We can develop waste treatment solutions that generate energy in the form of steam, hot water or electricity that each company can later use for internal processes.

   6. Generation of energy from the waves

                The first wave energy management plant was built in Aguçadoura, Portugal, eight kilometers away from the coast. The plant has a capacity of 2.25 MW and is able to supply electricity to up to 1500 homes. The installation consists of steel tubes floating on the ocean surface, measuring 3.5 m in diameter and 150 meters long, called “Pelamis”. Those components are semi submerged in the sea and are responsible for transforming the movement of the waves into electrical energy.

   7. Vehicles that do not emit gases

                Known as ecological vehicles, they are so called because their use does not negatively influence the environment and contributes to reducing the presence of polluting gases in the atmosphere, mainly carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxide (NOx), unburned hydrocarbons (HC) and compounds of lead and Sulphur dioxide.

   8. Harnessing solar energy

                Perhaps these are the systems that have been worked on and researched the most. Examples of solar energy conversion technologies are high vacuum tubes for hot water, polypropylene collectors for hot water, photovoltaic collectors to produce electricity and solar street lamps, among others. All those technologies aim to reduce dependence on energy from hydrocarbons and fossil fuels and promote greener solutions.

   9. Vertical gardens and farms

                The installation of vertical gardens in buildings also helps save energy and brings many benefits to the environment. Vertical gardens don’t need watering routines that involve unnecessary use of water, and because they are installed along a wall, they reduce the intense hearing pollution that comes from the outside and even that one that you can generate. Moreover, it helps isolate the high temperatures that are presented by climate change, resulting in significant savings in energy, heating and air conditioning. If we extrapolate this technology to farms, we can save a lot of water and take care of the fertile soil. Today, there are vertical farms of up to 100 hectares. In the perspective of Bangladesh this is one of the best steps to move forward for creating an environment friendly country.

   10. Natural gas boilers

                Green boilers are boilers that consume as little fuel as possible or use renewable energy. Natural gas, although it is also a fossil fuel, has the particularity that it emits almost no toxic gases such as nitrogen oxides, particles, carbon monoxides nor Sulphur. It releases more water vapour and less carbon dioxide. It is the most environmentally friendly fossil fuel in terms of emissions, with 204 grams of CO2 per thermal kW/h. Therefore, natural gas boilers tend to be condensed, which means that they recover the heat from the water vapour coming out of the chimney, achieving higher thermal yields with less air pollution.          

  11. Off-shore Wind Power

                One of the last great hurdles for renewable energy is offshore wind turbines located just off the coast that can generate near-constant green power. Experts say wind could provide up to one fifth of world demand of electricity within the next 15 years. The UK government is legally committed to delivering 15 per cent of its energy demand from renewables by 2020. As of 2014, Denmark is generating around 40 per cent of its electricity from wind. But surprisingly, fossil fuel subsidies reached $500 billion globally in 2011 whereas renewable energy subsidies reached $88 billion in the same year. There is no disputing that some energy subsidies counter the goal of sustainable development, as they may lead to higher consumption and waste, exacerbating the harmful effects of energy use on the environment, creating a heavy burden on government finances and weakening the potential for economies to grow.

Swiss semiconductor maker STMicroelectronics has saved more than $60 million by cutting its energy usage and $20 million by reducing water consumption below baselines set in 1994. The company issued some environmental goals and empowered its divisions to become creative: the responses include using solar power and finding ways to recycle water. Cargill Dow is manufacturing biodegradable and recyclable plastics from corn sugars. The key to sustainability is to make the market work for, and not against, the environment. British Oil giant, BP decided in 1997 to reduce its carbon emission by 10 per cent below 1990 levels. In the year 2001 a report by Baxter International, a medical products maker, detailed how reductions in energy, water use, improved waste disposal and recycling over the past seven years cut costs by $53 million.

Green technology is crucial for the implementation of the Sustainable Development Goals. Currently, there is an urgent need to form a long-term mechanism for screening, evaluation and promotion of appropriate green technology. Therefore, the Green Technology Bank was initiated as a new platform to bridge the gaps between different stakeholders and promote the innovation and transfer of green technology. However, lack of standardized classification system may hinder the pace and depth of green technology development. In our country, the first step towards green innovation needs to come from the government. While they have been successful in pushing green technology in some sectors, such as banking, they haven't really looked into many other important sectors, such as construction and architecture.


Nadira Islam, a student of Department of Environmental Science and Engineering, Jatiya Kabi Kazi Nazrul Islam University, Trishal, Mymensingh