What can you do to reduce your energy consumption?

Energy, Let's save it! 

https://www.youtube.com/watch?v=1-g73ty9v04

This video gives a good summary on the impacts of our increase use of energy as well as what an individual to play a part in reducing our energy consumption. The video mentioned the switching off of lights when not in use, car pooling, lowering down the temperatures of aircon, use of energy saving light bulbs etc. To add on to what is being mentioned, I think it is very important to look out for the energy label of a product when purchasing a new product. 

Energy ratings 

Look out for the energy ratings in its description or the logo that shows that it is labelled as an energy efficient product. In Singapore, the more energy efficient the product is, the more ticks it has. To know more about the reading of the energy label in Singapore, click here. This is especially useful when buying household appliances that consume a large amount of energy such as the air conditioner and refrigerator. 

References: 

Nea.gov.sg,. (2015). Tips on Buying Energy Efficient Appliances. Retrieved 28 October 2015, from http://www.nea.gov.sg/energy-waste/energy-efficiency/household-sector/tips-on-buying-energy-efficient-appliances

Public perceptions of energy consumption and savings

After sharing much about energy consumption and production on a national and global scale, I would like to talk about what individuals can do to save and reduce energy consumption. In this blog post, I will be sharing about the journal article on public perceptions of energy consumption and savings which illustrates what needs to be improved to help consumer make wiser decisions with regards to the usage of energy. 

Research done in the article has shown that most participants focused more on curtailment such as the switching off of lights rather than using energy efficient products such as more efficient light bulbs and refrigerators. Only 11.7% of the participants mentioned that efficiency improvements are a way to conserve energy while 55.2% mentioned curtailment activities. The article explains that the public might feel that curtailment is easier to carry out and of lesser cost as compared to energy efficient products that have to be bought. This suggests that the public can do more to reduce their energy consumption. 

In addition, participants in general did not recognise energy differences across devices and activities. It has been noted that participates estimated that central air conditioner consumes 1.3 times more energy than a room air conditioner. In reality, a central air conditioner consumes 3.5 times more energy than a room air conditioner. Another example is that participants estimated that trains, ships and trucks consume roughly about the same amount of energy. However, it has been reported that trucks consume 10 times more energy per ton-mile. It is indeed a concern that participants fail to recognise these huge differences. This would mean that there are likely to opt for the less energy efficient option when there are other better alternatives available. This can pose as a hindrance to our pursuit of reducing our energy consumption and the release of greenhouse gases. Hence, the article suggests that there is a need to bridge this gap in knowledge. I agree to what the article says and the government can play an active role in promoting energy efficiency improvements more than curtailment activities. I also feel that as we often place an emphasis on greater improvements in technology to create more energy efficient appliances, we may tend to neglect that the consumers are not able to keep up with the progress. This is because that the consumers fail to see the effectiveness of the energy efficient products and hence little is done to reduce energy consumption and savings. Therefore, I think that it is important that efforts are also channeled to making sure the consumer makes wiser decisions with regards to energy consumption. 

References: 

Attari, S., DeKay, M., Davidson, C., & Bruine de Bruin, W. (2010). Public perceptions of energy consumption and savings. Proceedings Of The National Academy Of Sciences, 107(37), 16054-16059. http://dx.doi.org/10.1073/pnas.1001509107

An overview of biofuel as a renewable energy source: development and challenges

In this journal article, it focuses on two advantages of biofuel which are decreasing the depletion of petroleum resources as well as to slow down climate change. However, it also mentions the potential problem of food insecurity and automotive engine incompatibility when biofuel is used. 

Biofuel are considered a cleaner alternative than the conventional coal used to generate electricity. The use of biofuel reduces the greenhouse gas (GHG) emissions released in the process of electricity generation. In this article, it points out at important point to calculate the "total lifecycle of biofuel from 'farm' to 'burn'" which consists of the factors shown in figure 1. The research in the article has estimated there would be a 50% reduction in greenhouse gas emissions when biofuel is used rather than coal. 

Figure 1

The article points out an interesting point that as international demands of energy rise, national policies are being set to encourage the production of biofuel. Subsidies are often given to increase the biofuel production. While this reduces GHG emissions, people worry that this may bring about food security issues. Under the national policy, forests are permitted to be cleared by burning to make way for the plantations. Biofuel can be categorised into biodiesel and bioethanol. Biodiesel are often produced from rapeseed, soybean and palm oil while bioethanol are being produced from the fermentation of sugarcane, corn, wheat and maize. The food used to produce the biofuel are mostly staple and primary products. If there is a decrease in supply of staple food, it may increase prices. Consequently, there is a fear that food will become less affordable for people which can pose as a big problem as food is necessary for survival. 

In addition, environmental damage can arise from the palm oil plantations. Forests are legal to be cleared under the national policy. This can possibly lead to a loss in biodiversity as habitats of the animals and plants are being destroyed. The article also raised that the wastage from plant mills such as fertilisers and insecticides can cause water pollution. When coming up with national policy, governments should consider the conservation of environment as they push for greater production of biofuel. 

References: 

Hassan, M., & Kalam, M. (2013). An Overview of Biofuel as a Renewable Energy Source: Development and Challenges. Procedia Engineering, 56, 39-53. http://dx.doi.org/10.1016/j.proeng.2013.03.087

Cigarette Butts As An Energy Source

I have recently came across an article in the Discover magazine talking about using the carbon in cigarette butts to generate electricity. In this blog post, I would like to share with you all about this new idea that caught my attention. 

According to research done by a group of South Korean scientists, the cigarette butts can be converted to porous carbon material as it contains cellulose acetate fibres. The carbon is a highly sought for material in creating supercapacitors as an energy storage system as carbon is low cost and have high electric conductivity and stability. The carbon from cigarette butts are known to be more efficient than conventional activated carbon. The advantages of using supercapacitors are short charging time, long life cycle and high power density. These supercapacitors are often found in portable electronic items. 

By using cigarette butts as an energy storage, it can be deemed as a greener way to produce supercapacitors. The cigarette butts are non-biodegradable in the environment and yet, as many as 5.6 trillion cigarette butts are disposed every year. With this new discovery of the alternative use of used cigarette butts, we can reduce our wastage and hence, reduce the impact on the environment. While we have discovered a good way to use cigarette butts, I hope that this will not increase the number of smokers in the world as smoking has great health impacts and can also result in air pollution. 

References: 

Lee, M., Kim, G., Don Song, H., Park, S., & Yi, J. (2014). Preparation of energy storage material derived from a used cigarette filter for a supercapacitor electrode. Nanotechnology, 25(34), 345601. http://dx.doi.org/10.1088/0957-4484/25/34/345601

Physics, I. (2014). Cigarette butts offer energy storage solution. Iop.org. Retrieved 16 October 2015, from http://www.iop.org/news/14/aug/page_63697.html

Is Hydroelectric Power really that Green?

Three Gorges Dam, China 

The Three Gorges Dam is the world largest hydroelectric power dam. This magnificent structure that dams the Yangtze river of China signifies the rise of hydroelectric power dams. In countries like Norway and Nepal, over 90% of electricity generated are from hydroelectric sources. In the United States, China and India, hydroelectric power constitutes around 15% of total electricity produced (Data.worldbank.org, n.d.). In this blog post, I will explore the benefits of hydroelectric dams as well as the potential harm it can bring about to the environment. 

Benefits of Hydroelectric Dams 

Hydroelectric dams can reduce the cost of electricity. They are usually quite durable and can possibly last for over 50 years with regular maintenance (Hydroelectricity Fact Sheet, 2012). While the initial cost of building the dams can be very large, the costs can be spread out over a long time and hence may appear to be a good investment for many countries. As countries make the switch over to hydropower, their reliance on oil and natural gas can be reduced. The volatility in prices of commodities such as oil and natural gas can lead to spike in the cost of electricity. By avoiding these large fluctuations that arise from commodities, countries feel more assured and costs of electricity can be stabilised and reduced. 

Another benefit from hydroelectric dams is the reduction in carbon dioxide emissions. This is because the use of hydropower ,unlike burning of fossil fuels, does not release carbon dioxide emissions. Water is used to turn the turbines of the generators to produce electricity. According to a study done by Paul Scherrer Institut and the University of Stuttgart, hydroelectricity release the least amount of greenhouse gas emissions when compared to other sources such as wind and nuclear energy (Dones et al., 2005). Hence, many countries are likely to adopt this strategy to produce electricity to reduce carbon emissions in an attempt to slow down global warming. 

Environmental Impacts of Hydroelectric Dams 

However, dams can possibly lead to increased greenhouse gas emissions too. The building of dams can lead to the formation of small reservoirs. Decomposition of organic matter in deep waters leads to a depletion of dissolved oxygen. This situation is worsened as waters in the reservoirs do not mix well and the dissolved oxygen in deep waters will not be replenished. Consequently, the reservoirs contain little or no dissolved oxygen. In low oxygenated waters, bacterial methanogenesis and denitrification results in the production of methane and nitrous oxide respectively (Friedl and Wüest, 2001). Both methane and nitrous oxide are greenhouse gases. It has been noted that methane is a more potent greenhouse gas than carbon dioxide. Methane has 72 times greater Global Warming Potential (GWP) as compared to carbon dioxide over 20 years (IPCC, 2007). The risks of increased release of potent greenhouse gases such as methane and nitrous oxide suggest that global warming may be aggravated, enhancing the detrimental consequences felt. 

Furthermore, dams can result in great loss of biodiversity. The presence of dams acts a physical barrier, segmenting the river. Spawning grounds for fishes are reduced and habitats are lost as marine creatures are no longer able to travel upstream. As a result, fish populations tend to decrease (Nilsson et al., 2005). Many dammed rivers may also support migratory species. Carex, located in the vicinity of the Three Gorges Dam in China, has been reduced in size to accommodate the dam. This area is particularly important because it provides food and water for the winter migratory birds (Xie et al., 2015). With a reduced land area, there will undoubtedly be lesser food and water supplies available for these migratory birds. It is plausible that there would be insufficient resources to support the population of migratory birds. It is noteworthy that these birds play a key role in pollination as well as controlling pests’ population. A decline in their population can possibly adversely impact biodiversity and upset global food chains. It can be observed that construction of dams do not only threaten local terrestrial species but can also have a greater impact on international biodiversity. 

Undeniably, hydroelectric power is still a much better option than using non-renewable energy such as coal and natural gas as the amount of greenhouse gas emissions are likely to be lower. While hydroelectric power should be encouraged, tighter regulations can be imposed in surveying the location for the building of dams and plans on how to reduce the damage done to the local ecosystem should be made. 

References 

Data.worldbank.org,. Electricity production from hydroelectric sources (% of total) | Data | Table. Retrieved 9 October 2015, from http://data.worldbank.org/indicator/EG.ELC.HYRO.ZS

Dones, R., Heck, T., Bauer, C., Hirschberg, S., Bickel, P., & Preiss, P. (2005). ExternE-Pol Externalities of Energy: Extension of Accounting Framework and Policy Applications.

Friedl, G., & Wüest, A. (2002). Disrupting biogeochemical cycles – Consequences of damming. Aquatic Sciences, 64, 55-65. doi:1015-1621/02/010055-11

Hydroelectricity Fact Sheet. (2012) (1st ed.). Retrieved from https://www.cleanenergycouncil.org.au/technologies/hydroelectricity.html

Nilsson, C. (2005). Fragmentation and Flow Regulation of the World's Large River Systems. Science, 308(5720), 405-408. doi:0.1126/science.1107887

Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.) (2007) Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. IPCC. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA

Xie, Y., Yue, T., Xin-Sheng, C., Feng, L., & Zheng-Miao, D. (2015). The impact of Three Gorges Dam on the downstream eco-hydrological environment and vegetation distribution of East Dongting Lake. Ecohydrol. Ecohydrology, 8(4), 738-746. doi:10.1002/eco.1543

The System Dynamics of Nuclear Energy in Singapore

Straits Times, 2010 

In recent years, Singapore has begun exploring other sources of energy to diversify from our reliance on natural gas (79%) and petroleum (19%). The Singapore government has chosen to explore the option of underground nuclear reactors. Having read a news article by the channel newsasia on this issue, it has piqued my interest to want to know more hence in this blog post, i would like to comment on the journal article entitled "The System Dynamics of Nuclear Energy in Singapore" published in the International Journal of Green Energy. This journal article mainly assesses the environmental, economical, social and political implications of building nuclear power plants in Singapore. In this blog post, I will mainly focus on the environmental impacts that can possibly arise from the nuclear reactors. 

The environmental implications of using nuclear energy is that there will be a reduction in carbon emissions from electricity generation. It has been noted that electricity generation contributes to 50 percent of the emissions in Singapore. Hence, by using nuclear energy, our carbon emissions can be lowered significantly. There is also a worry of potential radiation pollution. The article reports an interesting fact that when the plant is properly managed, the radiation emitted is lower than natural radiation that we are exposed to. Thus, the public should be reassured that radiation levels are actually not harmful. 

Another concern is thermal pollution. This is due to the release of hot water used after cooling the plant. This hot water when released back into the sea can increase water temperatures and the rates of decomposition. Consequently, dissolved oxygen will deplete and the marine ecosystem will be adversely affected. Great biodiversity may be lost where 90% variety of marine species are destroyed due to the Diablo Canyon nuclear power plant in United States. The article proposed to purify the warm water through desalination plants so that they can be used for drinking water. I feel that this idea may not be very practical as the water from the nuclear reactors are likely to be contaminated. If it is indeed possible to purify the water for drinking, it will also be hard for society to accept and drink it. Hence, it may not be very feasible to use the warm water released from nuclear plants and purify it for drinking. 

Nuclear waste management is another significant concern when it comes to nuclear power plants. The article states that the anxiety of nuclear waste storage in Singapore is "greatly exaggerated according to Palmer, Ramakrishna, and Cheema (2010)". The British nuclear plants were used as an example to show that only 1090m³ of high-level waste (HLW) is produced from 41 reactors and taking into account the creation of nuclear weapons. This amount of waste only required a standard size of basketball court to be filled to below the level of the baskets. While the article portrays this optimistically that Singapore would have sufficient space to contain the waste, I am quite skeptical about the nuclear waste management in Singapore. The article mentions that 236000m³ and 3190000 m³ of intermediate-level waste (ILW) and low-level waste (LLW) respectiely, are produced in a day. [HLW refers to waste that are of high temperatures and radioactivity, ILW are of lower temperatures and radioactivity and ILW includes materials such as protective clothing.] Taking the data of the British nuclear reactors and assuming that Singapore operates a nuclear reactor for 50 years, the HLW, ILW and LLW produced are 48152m³, 105,048,780m³, 1,419,939,024m³ respectively. If we want to store this nuclear waste, we would require around 24 Semakau landfills (Semakau landfill has a capacity of 63 million m³ and stores our incinerated waste (National Library Board).) If Singapore is planning to capitalise on nuclear power, nuclear waste management is an issue of paramount importance to be considered. 

While costs of energy from harnessing nuclear power is much lower than the cost of natural gas and oil sources, it may be difficult to get the public to accept the building of nuclear reactors due to the safety concerns. Furthermore, there are also environmental concerns with regards to the use of nuclear power. If Singapore is really keen on building an underground reactor, I think the design and management is very crucial. This is because Singapore, unlike other countries that capitalise on nuclear power, is land scarce and are likely to be found directly below our homes. 

References

Chia, E., Lim, C., Ng, A., & Nguyen, N. (2014). The System Dynamics of Nuclear Energy in Singapore. International Journal Of Green Energy, 12(1), 73-86. http://dx.doi.org/10.1080/15435075.2014.889001

National Library Board, S. (2015). Pulau Semakau | Infopedia. Eresources.nlb.gov.sg. Retrieved 3 October 2015, from http://eresources.nlb.gov.sg/infopedia/articles/SIP_1008_2010-03-22.html