Month: March 2018

2.0 Searching for a promising source of renewable energy

We have previously discussed different forms of ocean energy, hydropower, wind power, biomass and geothermal energy in detail. Finally, we realized that none of them could fulfil the ever-increasing global energy demand.

So… What sort of conclusions can we draw from our previous discussions?

Is it still realistic to expect 100% renewable energy from the aforementioned energy sources?

Before moving onto the talking point, let us go back to some important facts that we discussed in our previous articles.

• As we realized, almost all the forms ocean energy technologies are harmful to marine lives and marine ecosystem.
• Construction of hydropower plants often requires residential areas to be relocated. In addition, hydropower plants cause various environmental and ecological problems. In some cases, hydropower plants also add greenhouse gases into the atmosphere thus accelerating the climate change (biomass buried in reservoirs decomposes releasing carbon dioxide and methane).
• Operation of wind turbines may be a big nuisance for nearby residents as wind turbines create a great deal of noise. Further, it is well known that wind turbines endanger the birds. They are life-taking bird killers. Especially, large-scale implementation of wind turbines believed to have a direct link with climate change [1]. On one hand, wind turbines would reduce the consumption of fossil fuels and release of greenhouse gases thus alleviating the climate change. On the other hand, they may alter the climate at local and global scales by extracting kinetic energy of winds.
• Biomass sector competes with other industries such as agriculture for valuable fertile land and water imposing a lot of pressure on food security, biodiversity and water supply.
• Use of geothermal energy leads to water and air pollution. In addition, many believe that geothermal plants create micro seismic waves.

Now let us take a look at the following table. It encapsulates the maximum amount of power that could be harnessed from various energy sources, according to our previous discussions.

Conclusion

• According to the table, wind power seems to be the only source of renewable energy of which technically viable power potential (71 TW) exceeds the current entire power demand (17.5 TW [9]). The maximum harvestable amount of power from wind is, however, less than the technical potential due to the fact that certain areas such as deep ocean, and environmentally/ ecologically, sensitive areas are unavailable for installing wind turbines. Such constraints obviously limit the practically harvestable wind power capacity. Although the economically viable amount of wind power is still uncertain many researchers have estimated its value at 2 TW (with current technology) [10]. In addition, wind power stations require a great deal of initial investment and large-scale energy storage as we discussed earlier.
• OTEC also seems to be a good candidate whose power potential is slightly greater than half the current power demand. However, OTEC technology is still not economically viable.
• Economically reachable tidal power capacity is estimated at about 0.09 TW (90 GW) [11] whereas technically viable tidal power potential is 3 TW. Moreover, almost all the forms of ocean energy require a great deal of capital investment and advanced technology.
• The worldwide hydropower electricity generation capacity was 1.01 TW (1010 GW) as of 2012 [12]. So, hydropower electricity generation has already reached a notable level.
• Biomass would reportedly be able to provide up to 5 TW by 2050. But it is very important to realize that biomass is sustainable if and only if we plant trees at the same or higher rate than we harvest biomass.
• As we realized in the previous article, economically viable geothermal electricity potential would be in the range of 1-2 TW. So, geothermal electricity would contribute merely 3.1% to the global energy demand by 2100. [8]

So,… as we all can realize, none of the above energy sources would be sufficient/ economically viable to fulfil the entire global energy demand which has been estimated to be 63 TW by 2100 [9].

Are there any other potential solutions?

Of cause!

We really do have a potential renewable energy source which can admittedly provide energy more than enough to fulfill the entire world’s energy demand!

It is already around us!

It would be definitely the best of the bunch though we have access to dozens of other renewable energy sources!

What is it?

Let us discuss it in detail from the next article.

1. Keith, D. W., DeCarolis, J. F., Denkenberger, D. C., Lenschow, D. H., Malyshev, S. L., Pacala, S., and Rasch, P. J. (2004). The influence of large-scale wind power on global climate. Proceedings of the national academy of sciences of the United States of America, 101(46), 16115-16120.
2. Pelc, R., and Fujita, R. M. (2002). Renewable energy from the ocean. Marine Policy, 26 (6), 471-479.
3. Sheth, S., and Shahidehpour, M. (2005, June). Tidal energy in electric power systems. In Power Engineering Society General Meeting, 2005. IEEE(pp. 630-635). IEEE.
4. Jones, A. T., and Finley, W. (2003, September). Recent development in salinity gradient power. In Oceans 2003. Proceedings(Vol. 4, pp. 2284-2287). IEEE.
5. Kaygusuz, K. (2002). Sustainable development of hydropower and biomass energy in Turkey. Energy Conversion and Management, 43 (8), 1099-1120.
6. Kempton, W., Pimenta, F. M., Veron, D. E., and Colle, B. A. (2010). Electric power from offshore wind via synoptic-scale interconnection. Proceedings of the National Academy of Sciences, 107 (16), 7240-7245.
7. Schiermeier, Q., Tollefson, J., Scully, T., Witze, A., and Morton, O. (2008). Energy alternatives: Electricity without carbon. Nature News, 454 (7206), 816-823.
8. Stefansson, V. (2005, April). World geothermal assessment. In Proceedings of the world geothermal congress(pp. 24-29).
9. Hu, A., Levis, S., Meehl, G. A., Han, W., Washington, W. M., Oleson, K. W., and Strand, W. G. (2016). Impact of solar panels on global climate. Nature Climate Change, 6 (3), 290-294.
10. Goswami, D. Y. (2008). A review and future prospects of renewable energy in the global energy system. In Proceedings of ISES World Congress 2007 (Vol. I–Vol. V)(pp. 3-10). Springer, Berlin, Heidelberg.
11. Esteban, M., & Leary, D. (2012). Current developments and future prospects of offshore wind and ocean energy. Applied Energy, 90(1), 128-136.
12. Sueyoshi, T., and Goto, M. (2017). World trend in energy: an extension to DEA applied to energy and environment. Journal of Economic Structures, 6(1), 13.

1.9 Geothermal energy

We have already discussed almost all the indirect solar energy sources which are unremittingly being replenished by the Sun. In this article, let us discuss another source of renewable energy. Geothermal energy!

Figure 1: A geothermal plant

Geothermal energy is a renewable source of energy. Just like any other renewable energy source geothermal energy is also naturally being replenished.

However, geothermal energy is not being replenished by the Sun! That means… Geothermal energy represents neither an indirect solar energy source nor direct solar energy source.

So….?

Geothermal energy: Where does it originally come from?

If geothermal energy is not being replenished by the Sun, where does it come from?

Is it really a renewable source of energy?

Well….

It is well known that earth’s interior is a huge heat reservoir with an incredible amount of energy in the form of heat!

This energy predominantly comes from two natural processes.

1. Formation of the earth (Primordial heat)

Figure 2: Earth’s layered structure

The entire solar system was formed from a solar nebula made of dust and gasses. After the Sun was formed, the remaining materials collapsed into planets, moons, comets and asteroids due to the gravitation. During the gravitational collapse of the Earth, an enormous amount of gravitational energy/ kinetic energy of collapsing particles/ debris was converted into heat which is now technically referred to as primordial heat of the Earth.

A substantial amount of the primordial heat still persists at the core of the Earth. This heat flows towards the Earth’s surface by conduction and radiates into the outer space thus causing the Earth to cool down with time

2. Decay of radioactive isotopes (Radiogenic heat).

Earth is a warehouse approximately to about three hundred isotopes. Some of them are stable whilst others are unstable (radioactive). As we know, radioactive isotopes decay into lighter nuclei releasing energy according to the Einstein’s equation. Long ago, Earth had had numerous radioactive isotopes which have released a vast amount of energy as they decay. Long-lived radioactive isotopes such as ⁴⁰₁₉K, ²³²₉₂Th, ²³⁵₉₂U and ²³⁸₉₂U [1] still play a crucial role pumping heat continuously to the Earth at a rate of 30 TW [2].

So… The Earth can be treated as a nuclear reactor with a capacity of 30 TW!

A huge natural nuclear power plant! It is fueled by several long-lived isotopes such as ,    ⁴⁰₁₉K, ²³²₉₂Th, ²³⁵₉₂U and ²³⁸₉₂U .

It is power capacity (30 TW) is equivalent to 30 000 nuclear power plants each with a capacity of 1000 MW!

Long-lived radioactive isotopes would keep pumping enough heat for several billions of years. Therefore, geothermal energy is a renewable source of energy.

Thermal energy comes from the above-mentioned mechanisms can be directly used for space heating or to produce steam which can be then used to generate electricity.

From the Earth → into the space……

The Earth’s temperature should have been rising with time as the radiogenic activity has been generating heat at a tremendous rate of 30 TW!

Earth is, however, a cooling planet!

It has already cooled down to create a habitable home-planet which was an inferno at the beginning. It will be further cooling down with time.

How does it happen?

Well…

As we know, heat is transferred from one place to another via three different mechanisms: Conduction, convection, and radiation.

Any object whose temperature is higher than 0 K radiates its thermal energy in the form of electromagnetic waves into its surrounding. Meanwhile, it would be absorbing radiation from its surround if its surrounding temperature is higher than 0 K. The rate at which an object radiates its thermal energy is proportional to the fourth power of the absolute temperature of the object. Similarly, the rate at which the object absorbs energy from its surrounding is proportional to the fourth power of the surrounding absolute temperature.

An object would be cooling if the object’s temperature is higher than that of its surrounding. The higher the temperature difference the higher the rate at which the object loses its thermal energy.

What about the Earth and its surrounding?

Figure 3: Planet Earth with its atmosphere

Earth’s average surface temperature is 287 K (14⁰ C) [3] while the temperature of the empty space is 2.7 K [4]. The temperature of the space nearby the Earth is, of course, much higher than 2.7 K. But it is still much lower than 287 K. As a result, the Earth has been losing its thermal energy leading to a cooling planet where billions of people and millions of other species live.

The average heat loss from the earth is estimated in the range of 43-45 TW [5]. In other words, our planet Earth is losing its geothermal energy at a rate of 43×10¹² J per second (at the lowest scenario).

Yes! It is equivalent to 43 000 000 000 000 J/s.

Moreover, it is nearly 2.5 times the current global energy demand (17.5 TW) and would be higher than the entire energy demand even by 2050 (25-30 TW) [6, 7]. But it is important to realize that none of the technology will be able to harness the entire amount of heat which reaches the Earth’s surface.

The worldwide geothermal electricity capacity in 2015 was estimated at 12.6 GW [8]. As we can see, it is insignificant compared to the rate at which Earth is losing its heat. The lower limit of the geothermal electricity potential is estimated at 50 GW while the upper limit is estimated to be in the range of 1-2 TW [5].

The table below shows the cumulative geothermal electricity generation capacity in several countries.

Table 01: Installed geothermal electricity generation capacity as of 2015 [8]

Some other facts about geothermal energy   

Currently, geothermal energy is being used

• For district heating and for other applications in 70 countries [9]
• To generate electricity in 24 countries [10]
• Iceland is a frozen land situated on a volcano! The country with a population of 300 000 meets 87% of its space heating requirement and 17% of its electricity demand with geothermal energy [11, 12] thanks to its geothermal resources.

Geothermal energy: Cons and pros

Advantages

• Renewable
• Provides an uninterrupted, regular supply of heat. Therefore, geothermal electricity can be used as a base load power source.
• Residual heat of the steam after generating electricity can be used for district heating or industrial applications.

Disadvantages

• High initial cost
• Some toxic materials such as mercury, antimony, and arsenic may come out with hot water from the geothermal sources.
• Geothermal plants often release various greenhouse gases and also some other harmful gases like radon (A radioactive gas). Hence, geothermal energy is not a carbon-neutral energy source and intensifies the greenhouse effect and climate change. In addition, some of such gases lead to acid raining. However, negative environmental effects of geothermal plants are less significant in comparison with those of coal-powered power plants.
• Most of the geothermal sources are neither technically nor economically viable.
• Potential geothermal energy sources are extremely limited and not readily available.
• Geothermal energy sources are exclusively site-specific. It is not a viable source of energy in most of the regions in the world.
• As mentioned earlier, the maximum geothermal electricity generation capacity has been estimated to be in the range of 1-2 TW. It would be merely 3.1% of the global energy demand by 2100 (global energy demand by 2100 would be 63 TW) [6]. Furthermore, it would require a substantial amount of capital investment and advanced technology to reach the upper limit of 2 TW from geothermal energy.

1. Barbier, E. (2002). Geothermal energy technology and current status: an overview. Renewable and sustainable energy reviews, 6 (1-2), 3-65.
2. Michaelides, E. E. (2012). Entropy production and optimization of geothermal power plants.
3. Jones, P. D., New, M., Parker, D. E., Martin, S., and Rigor, I. G. (1999). Surface air temperature and its changes over the past 150 years. Reviews of Geophysics, 37(2), 173-199.
4. Fixsen, D. J. (2009). The temperature of the cosmic microwave background. The Astrophysical Journal, 707(2), 916.
5. Stefansson, V. (2005, April). World geothermal assessment. In Proceedings of the world geothermal congress(pp. 24-29).
6. Hu, A., Levis, S., Meehl, G. A., Han, W., Washington, W. M., Oleson, K. W., and Strand, W. G. (2016). Impact of solar panels on global climate. Nature Climate Change, 6 (3), 290-294.
7. Blanco, J., Malato, S., Fernández-Ibañez, P., Alarcón, D., Gernjak, W., and Maldonado, M. I. (2009). Review of feasible solar energy applications to water processes. Renewable and Sustainable Energy Reviews, 13 (6), 1437-1445.
8. Bertani, R. (2016). Geothermal power generation in the world 2010–2014 update report. Geothermics, 60, 31-43.
9. Fridleifsson, I. B., Bertani, R., Huenges, E., Lund, J. W., Ragnarsson, A., and Rybach, L. (2008, January). The possible role and contribution of geothermal energy to the mitigation of climate change. In IPCC scoping meeting on renewable energy sources, proceedings, Luebeck, Germany(Vol. 20, No. 25, pp. 59-80). Citeseer.
10. Holm, A., Blodgett, L., Jennejohn, D., and Gawell, K. (2010). Geothermal energy: international market update. Geothermal energy association, 7.
11. Ragnarsson, Á. (2003). Utilization of geothermal energy in Iceland. 000599234.
12. Bertani, R. (2007). World geothermal generation in 2007.

1. By T. AGEMAR – Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=56501672
2. By CharlesC (Own work composite) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons
3. By No machine-readable author provided. Heikenwaelder assumed (based on copyright claims). – No machine-readable source provided. Own work assumed (based on copyright claims), CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=733587

In previous article, we discussed the pros and cons of hydropower. In this article, let us discuss why hydropower is important than other types of renewable energy sources, we discussed in previous articles.

We have already discussed several types of renewable energy sources. Almost all the renewable energy sources except reservoir hydro are intermittent. Also, some of them including hydropower are seasonal dependent.

Intermittent energy sources are energy sources of which power output fluctuates with time. For instance, the velocity and direction of wind vary with time and thus the electric power generated by a wind turbine fluctuates according to the rhythm of the wind speed and direction. This intermittent nature of renewable energy sources negatively affects the grid’s stability and makes it difficult to maintain the load balancing thereby limiting the amount of intermittent energy to be grid-connected. Especially, if the grid largely relies on intermittent sources, the grid should have a mechanism to balance the power demand and power input to the grid. This requires large-scale (pumped hydro, compressed air) and small-scale energy storage (Flywheel, battery, superconducting magnetic energy storage) systems. Such systems are expensive to build and maintain. Therefore, they increase the cost of electricity delivered to the utility customers. However, reservoir hydropower plants can largely replace the role of both large-scale and small-scale energy storage systems thanks to their flexibility and short response time. In a nutshell, hydropower enables the grid to accommodate more and more intermittent energy sources while working as a renewable energy source.

Hydropower is not only a renewable source of energy but also a renewable energy-marketing executive!

Hydropower plants,

• Generate electricity with no emission!
• Enhance the grid’s stability, and power quality!
• Promote other renewable energy sources!
• Reduce the cost of electricity by reducing the need for energy storage systems!

Technically feasible worldwide hydropower capacity and currently available hydropower capacity are 2.36 TW (2360 GW) 970 GW as mentioned earlier [1, 2]. In other words, hydropower can potentially shut down as many as 1390 coal power plants each with a capacity of 1000 MW in future.

Of course, as we discussed in previous articles, worldwide capacity of wave power, ocean thermal energy, osmotic power or tidal power would not be sufficient to satisfy the increasing global energy demand, not to mention hydropower!

However, hydropower can still play a vital role in the battle for climate change since it can help the grid accommodate more and more intermittent and seasonal dependent energy.

Hydropower is the marketing executive in green energy industry!!!

Waste is not to be wasted

Waste is an unnecessary product in our daily life. We do not generate waste purposely. But we cannot stop generating waste though it is unwanted/ unpleasant.

Waste was commonly considered a waste for centuries.

Of course… Waste generation still remains a big challenge.

We should try our best to reduce waste generation as much as possible since waste leads to many negative impacts on our health, economy, environment and society.

How to reduce waste generation?

The best solution to reduce waste generation is to follow the 5R concept.

• Refuse: Refuse to purchase
• Reduce: Reduce consumption
• Reuse: Reuse the same product over and over
• Recover: Recover usable components for other uses
• Recycle: Recycle any remaining waste

The 5R concept is a proven concept in waste management. However, it is obvious that no single waste management strategy can completely shut off the daily waste generation though some concepts may help reduce the amount of waste to some extent.

So….

What can we do to manage waste?

Waste-to-energy probably would be one of the best solution in waste management.

Waste-to-energy: Waste is not a waste

• Burying waste in landfill and recycling are two common solutions in traditional waste management. Composition of waste varies from country to country, from region to region and even from year to year.
• Organic waste accounts for a significant portion of garbage in an average household. As its name implies, organic waste is a waste which is a challenge and should be properly managed.

However, organic waste is one of the different forms of biomass, as we discussed earlier. Solar energy stored in biomass during photosynthesis can be used to generate electricity or heat.

The technology which uses waste to generate electricity in the form of either electricity or heat is commonly known as waste-to-energy. Several waste-to-energy concepts have already been used to generate electricity. Both thermal techniques such as incineration, pyrolysis and gasification and also non-thermal techniques such as anaerobic digestion are currently being used.

Waste is continually generated by us. So, waste-to-energy is a renewable/ sustainable energy technology. And it does not lead to global warming or climate change since waste (biomass) which is the primary fuel in waste-to-energy plants is carbon neutral.

Goal of waste-to-energy technology

Waste-to-energy plants generate energy from waste which is one of the main challenges in the 21^stcentury. In other words, waste to energy technology converts problems into a solution.

Waste-to-energy plants generate electricity or heat from waste. Also, they help alleviate the waste problem. So, waste to energy is a win-win technology.

It has been estimated that an average person in developed countries and developing countries annually generates 521.95–759.2 kg and 109.5–525.6 of waste, respectively [1]. Further, organic waste, paper and plastic accounts for 46%, 16% and 10% of municipal solid waste (Hoornweg & Bhada-Tata 2012). Simply, nearly three quarters of municipal solid waste can be used to generate electricity or heat while greatly reducing the amount of waste.

Anyway, one of the main challenges in waste-to-energy is that they require a continuous supply of combustible waste. Also, most of the waste-to-energy technologies have a lower limit for waste supply. The minimum amount depends on the technology used. This implies not all the regions in the world would be suitable for waste-to-energy plants though waste generation is a common practice in our daily life regardless of the country or region.

1. Karak, T., Bhagat, R. M., and Bhattacharyya, P. (2012). Municipal solid waste generation, composition, and management: the world scenario. Critical Reviews in Environmental Science and Technology, 42(15), 1509-1630.

Biomass: Potential as a renewable energy source

Biomass, probably the oldest energy source of humanity, still provides about 10.5% of today’s global energy demand [1].

Traditional biomass (firewood, agricultural residue, cow-dung and charcoal) which makes up 8.48% of the global energy demand is mainly being used for cooking and heating [2]. It is largely harvested in developing countries in Asia and Africa. In traditional practices, people do not ensure another generation of trees. They use biomass as an energy source in traditional biomass stoves which are inefficient and unsafe. Therefore, traditional biomass is neither sustainable nor safe though it is a readily available energy source and as such, extensive use of traditional biomass leads to deforestation and intensifies the climate change.

Biomass is renewable (modern biomass) if and only if it is produced in a sustainable way!

Modern biomass (combustible waste, forest residue, sugarcane, etc.), on the other hand, is predominantly being used in developed countries and also in Brazil to generate electricity/ heat or to produce ethanol, methanol or hydrogen. Unlike traditional biomass, modern biomass is considered a renewable energy source since modern biomass is produced sustainably. Currently, modern biomass provides as little as 1.9% of global energy demand. The interest of the modern biomass as a renewable energy source, however, is growing and of paramount importance as its potential is much higher than its present-day share.

Current worldwide biomass-based electricity generation capacity is estimated at 112 GW. According to recent assessments, the potential of biomass energy by 2050 would be around 5 TW [3]. Thus, modern biomass seems to be a promising source of renewable energy. It helps mitigate the waste problem, lowers the greenhouse gas emission and alleviates the climate change.

However…It is important to realize that 5 TW of power from biomass is equivalent to billions of trees/crops grown in half a billion hectares on our own living planet.

Would this planet earth be able to accommodate such a number while providing space for homes, roads, buildings, cultivation, etc. for 9 billion people [4]?

May be!

But…Just think!

Should we waste already stressed virgin land in the name of biomass?

Should we massacre priceless forests in the name of biomass?

Should we despoil dwelling homes of wildlife in the name of biomass?

Should we consecrate billions of hectares for biomass production in the name of biomass?

Certainly should not…if we have access to other potential renewable energy sources.

Let us see if there such renewable energy sources in next articles.

1. Demirbas, A., and Arin, G. (2002). An overview of biomass pyrolysis. Energy sources, 24 (5), 471-482.
2. Goldemberg, J. (2007). Ethanol for a sustainable energy future. Science, 315(5813), 808-810.
3. Schiermeier, Q., Tollefson, J., Scully, T., Witze, A., and Morton, O. (2008). Energy alternatives: Electricity without carbon. Nature News, 454 (7206), 816-823.
4. Fischer, G., Hizsnyik, E., Prieler, S., van Velthuizen, H., and Wiberg, D. (2012). Scarcity and abundance of land resources: competing uses and the shrinking land resource base.

1.8 Biomass

Biomass, as the name implies, refers to biological or organic materials. Simply, biomass represents either living or dead, animal and plant materials.

Wood chips, tree branches, biodiesel, landfill gas, ethanol, coconut shells, and sewage sludge represent direct sources of biomass. In addition, various forms of organic waste such as kitchen garbage, cow-dung, straw, poultry litter, yard clipping, sawdust, and rice husk are also excellent sources of biomass fuels. Anyway, plant materials account for nearly the entire amount of worldwide biomass fuel consumption.

Plants

Plants are natural food factories and air purifiers!

• They draw water and nutrients from ground through their root system.
• Leaves absorb carbon dioxide from the atmosphere through small holes of the leaves called stomata.
• Chloroplast containing a green pigment called chlorophyll absorbs sunlight.
• Chloroplast converts water, CO₂, and minerals into food by using solar energy. During the process, solar energy is stored in food in the form of chemical energy and O₂ is released into the atmosphere as a byproduct. This process is called photosynthesis.
• In a nutshell, trees act as natural food factories and air purifiers. Their food making process is called photosynthesis.

An outline: The food-making process (Photosynthesis)

Raw materials: Water, minerals, and CO₂

Energy source: Solar energy

Byproduct: Oxygen

Final product: Food (Energy storage)

So…. As we can see, trees store solar energy in the form of chemical energy during photosynthesis. During the same process, CO₂ is absorbed from the atmosphere thereby lowering the greenhouse effect.

Trees have been assigned to produce food by nature, besides being to be the key player in natural carbon recycling!

Biomass: Is it sustainable?

All of the aforementioned sources of biomass fuels capture and store solar energy in the process called photosynthesis and it is an unremitting process.

We can grow plants to harvest biomass materials. The harvested organic sources are used to generate electricity or heat. Obviously, carbon dioxide is released when they are burnt. However, we can regrow the plants within a short period of time so that the same or higher the amount of released carbon dioxide is recycled back. Hence, biomass is considered to be a renewable energy source.

• Biomass is a renewable or sustainable source of energy (Plants can be regrown within a short period of time).
• Biomass is an intermediate state of the carbon cycle and therefore, it is carbon neutral (Plants absorb CO₂ from the atmosphere and release back when they are burnt. The released amount of CO₂ would be recaptured by the next generation of plants thereby making it a never-ending, carbon neutral process).

People have widely been using biomass, especially for cooking since ancient times. From recent years, however, it is also being used for electricity generation and industrial energy needs in the form of heat.

Developed countries use biomass fuels mainly for electricity generation whereas it is widely being used in developing countries such as India, Pakistan, and Bangladesh for cooking. Especially, Brazil which is a developing country use biomass in large-scale for both electricity generation and ethanol production (to power cars).

So, it is undoubted that Brazil is the best example for a country which has already replaced thousands of gasoline-powered cars by ethanol-powered automobiles.

Fossil fuels or biomass? Both fossil fuels and biomass release greenhouse gases during combustion.

Combustion of biomass fuels, of course, releases greenhouse gasses into the atmosphere. But…Unlike fossil fuels, biomass fuels, however, can be produced within a short period of time as mentioned earlier and therefore, can replace the use of nonrenewable energy sources to some extent. Furthermore, biomass is said to be a carbon-neutral energy source since carbon dioxide emitted during the combustion is neutralized during the next biomass production (photosynthesis). Thereby, biomass as a fuel can lower the emission of greenhouse gasses and alleviate climate change to a certain extent.