Thursday | 16 January 2025 | Reg No- 06
বাংলা
   
Thursday | 16 January 2025 | Epaper

Renewable energy: Next source of power

Published : Saturday, 20 February, 2021 at 12:00 AM  Count : 1527
Md Zillur Rahaman
Md Zillur Rahaman

Md Zillur Rahaman

Renewable power is booming, as innovation brings down costs and starts to deliver on the promise of a clean energy future. It means that renewables are increasingly displacing "dirty" fossil fuels in the power sector, offering the benefit of lower emissions of carbon and other types of toxic waste. But not all sources of energy marketed as "renewable" are beneficial to the environment. Biomass and large hydroelectric dams create difficult tradeoffs--considering the impact on wildlife, climate change and other issues.
Renewable energy is produced from the sources that do not deplete or can be replenished within a human's life time. The most common examples include wind, solar, geothermal, biomass and hydropower. Most of the renewable energy is derived directly or indirectly from the Sun. Sunlight can be used directly using solar technologies. The Sun's heat drives winds, whose energy is captured with turbines. Plants also rely on the Sun to grow and their stored energy can be utilized for        bio-energy.

While renewable energy is often thought of as a new technology, harnessing nature's power has long been used for heating, transportation, lighting, and so on. Wind is used to sail boats in the seas. Windmills grind grain--powered by wind. The Sun provides warmth during the day. But over the past 500 years or so, humans increasingly turned to cheaper, dirtier energy sources such as coal and fracked gas.
Now we have innovative and less-expensive ways to capture and retain wind and solar energy. As a result renewables are becoming a more important global power source. The expansion in renewables is also happening at scales large and small, from rooftop solar panels on homes that can sell power back to the grid to giant offshore wind farms. Even some entire rural communities rely on renewable energy for heating and lighting.

Humans have been harnessing solar energy for thousands of years--to grow crops, stay warm, and dry foods. Solar cells are made from silicon or other materials that transform sunlight directly into electricity. Distributed solar systems generate electricity locally for homes and businesses, either through rooftop panels or community projects that power entire neighbourhoods. Solar farms can generate power for thousands of homes, using mirrors to concentrate sunlight across acres of solar cells. Floating solar farms--or "floatovoltaics"--can be an effective use of wastewater facilities and bodies of water that aren't ecologically sensitive.  

Hydropower is the largest renewable energy source for electricity in the United States, though wind energy is soon expected to take over the lead. Hydropower relies on water--typically fast-moving water in a large river or rapidly descending water from a high point--and converts the force of that water into electricity by revolving a generator's turbine blades.

Nationally and internationally, large hydroelectric plants--or mega-dams--are often considered to be non-renewable energy. Mega-dams divert and reduce natural flows, restricting access for animal and human populations that rely on rivers. Small hydroelectric plants (below 40 MW), carefully managed, do not tend to cause as much environmental damage, as they divert only a fraction of flow.

Biomass is organic material that comes from plants and animals, and includes crops, waste wood, and trees. When biomass is burned, the chemical energy is released as heat and can generate electricity with a steam turbine. It is often mistakenly described as a clean, renewable fuel and a greener alternative to coal and other fossil fuels for producing electricity. However, recent science shows that many forms of biomass--especially from forests--produce higher carbon emissions than fossil fuels. There are also negative consequences for biodiversity. Still, some forms of biomass energy could serve as a low-carbon option under the right circumstances.

Renewable energy accounts for 13.5 per cent of the world's total energy supply, and 22 per cent of the world's electricity. Many of these renewable sources still face difficulties in being deployed at a large scale including, technological barriers, high start-up capital costs, and intermittency challenges. It is important to note that the terms 'renewable energy', 'green energy' and 'clean energy' are not interchangeable in all cases. 'Green energy' is a subset of renewable energy, which boasts low or zero emissions and low environmental impacts to systems such as land and water.

Coal-based power plants are becoming obsolete globally and such projects should not be continued in Bangladesh as well. China, Japan, India and the UK have already banned the coal based power plants in their own country but they are investing heavily in Bangladesh's coal power plants whereas renewable energy can replace them as a lower cost alternative for electricity generation.

Bangladesh has given topmost priority to the power sector and has prepared short, medium and long-term power generation plans using gas, coal, duel fuel, nuclear and renewable energy resources. Renewable energy will play a vital role in meeting the demand for electricity, especially in the off-grid areas of the country. The government had set a target to generate 5 per cent of the total electricity supply from renewable energy resources by 2015 and 10 percent by 2020. Unfortunately, it has achieved only 3 per cent of the target till now.

The prospect of renewable energy in Bangladesh is bright, particularly for solar energy. In the near future, renewable energy will remain a supplement to the conventional energy production. Still renewable energy is playing an important role in reaching consumers outside the national grid or in places where grid connection is delayed.

In Bangladesh, the majority of the population relies on biomass for cooking and heating. About 90 per cent of the energy required to meet household cooking demand comes from biomass sources. There are around 30 million households in Bangladesh, the majority of which are rural. Few are aware that the toxic fumes produced by cooking can pose a serious risk to health--especially to women and children. It is estimated that more than 24 million rural and nearly 6 million urban Bangladeshis are exposed to household air pollution due to solid fuel use. The pollutants released by burning solid biomass also contribute to climate change.

Commendable progress has been made globally in the renewable energy sector in the last few years. At present, about 700 MW is being generated from renewable energy sources in Bangladesh. Solar Home System (SHS) is a success story in Bangladesh. This system does not produce air pollutants or greenhouse gases and for this it will be the next prime source of energy system in home and abroad.
The writer is a banker and freelance    contributor











LATEST NEWS
MOST READ
Also read
Banning outdoor New Year parties
BAC in higher education in Bangladesh
It's time to end the bloodshed in Yemen
Plastic waste threatens environment and biodiversity
Fair, reasonable and non-discriminatory export control is an important guarantee for globalization
Rapists still having a field day in Bangladesh
Int’l cooperation with BRI
Olaf Scholz: Agenda of Germany’s new leader
Editor : Iqbal Sobhan Chowdhury
Published by the Editor on behalf of the Observer Ltd. from Globe Printers, 24/A, New Eskaton Road, Ramna, Dhaka.
Editorial, News and Commercial Offices : Aziz Bhaban (2nd floor), 93, Motijheel C/A, Dhaka-1000.
Phone: PABX- 41053001-06; Online: 41053014; Advertisement: 41053012.
E-mail: district@dailyobserverbd.com, news©dailyobserverbd.com, advertisement©dailyobserverbd.com, For Online Edition: mailobserverbd©gmail.com
🔝
close