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Ramachandra T.V.,Sustainable Transportation and Urban Planning | Hegde G.,Center for Sustainable Technologies astra | Krishnadas G.,Energy and Wetlands Research Group
International Journal of Renewable Energy Research | Year: 2014

Wind is one of the viable renewable energy resources with a promising potential of feasible alternative to fast depleting fossil fuels. Wind mills for grinding grains and pumping water have been used in rural areas since centuries. It can be advantageously harnessed in a decentralized manner for various applications in remote localities and rural areas. Water pumping through decentralized energy promotes multiple cropping, which helps in the provision of local employment and also the development of a region. Wind resource assessment is the primary step towards understanding the local wind dynamics and evaluating available potential of a region. Climatic average datasets of meteorological variables containing wind speed data for the period between 1961 and 1990 (compiled from various sources) were used for the potential assessment of wind speed in Uttara Kannada district, Karnataka State, India. These were validated with the ground data of meteorological observatories at Karwar, Honnavar and Shirali which were obtained from the Indian Meteorological Department, Government of India, Pune. Analyses showed seasonal variations of wind speed in the region. Wind speed varies from 1.9 ms-1 (6.84 km/hr) to 3.93 ms-1 (14.15 km/hr) throughout the year with minimum in October and maximum in June and July (Monsoon). The district experiences mean annual wind speed of 2.5 ms-1 to 3.0 ms-1 in all taluks, fostering prospects for Wind Energy Conversion System (WECS) installation. Decentralized electricity generation from WECS and hybridizing wind energy systems with other locally available resources (solar, bioenergy etc.) would assure the supply of reliable energy to meet the energy demand of the respective regions.

News Article | March 1, 2017
Site: www.theguardian.com

On the evening of Thursday 16 February, residents in the south-east part of Bangalore noticed huge plumes of smoke rising into the sky. The smoke was coming from the middle of Bellandur Lake – the biggest lake in the city at a little over 890 acres. They realised the seemingly impossible had happened: the lake had caught fire. Even fire fighters wondered how a blaze in water could be put out. The fire in the lake burned for 12 hours and left behind a sinister black patch in the centre, according to some eye-witness accounts. This is the new story of Bangalore – state capital, India’s Silicon Valley, and once upon a time, the “city of lakes”. The reasons why these lakes are able to catch fire begin to explain why scientists at the influential Indian Institute of Science believe Bangalore will be “unliveable” in a few years’ time. A lethal mix of factors create an environment that merely requires the slightest of triggers for lakes to go up in flames. Untreated effluents pour into the waters from the many industries and homes on its banks, illegal waste disposal takes place on a large scale – often including rubbish which is set on fire – and invasive weeds cover large swathes of the lake in a thick green canopy. The latest incident is not the first time the lake has caught fire; it happened in May 2015. A few days later, it was in the news again for being covered in snow-like froth, which began to swirl up in the summer wind, engulfing passers-by. The froth was the result of chemical waste dumped in the lake, and was toxic enough to crack windshields, wear the paint off car hoods and exacerbate the severe respiratory issues that have plagued citizens in recent years. Dr TV Ramachandra, coordinator of the Energy and Wetlands Research Group at the Indian Institute of Science (IISc), has been studying the lakes in Bangalore, especially Bellandur and Varthur, for over two decades. He explains that an estimated 400-600 million litres of untreated sewage is let into the lake catchment every day, creating a toxic environment fertile for disasters like the fires and foam. “The city overall generates between 1,400 and 1,600m litres per day of untreated sewage,” he says. “20-30m litres per day is generated from the apartments in the vicinity of Bellandur Lake. There are several invasive species like water hyacinths growing in the lake, thick enough to walk on. People dump solid waste on top of it. Because of the thickness, it creates an anaerobic environment in the water below, where methane is formed. It creates an ideal environment for catching fire.” He believes there are too many agencies governing the lake, so they all blame each other for such incidents. “The Bangalore water supply and sewerage board should be held responsible for letting the untreated sewage into the water,” he says, adding that the onus should also be placed on the Karnataka state pollution control board for not regulating industries that have been draining their untreated sewage into the lake. Although the Water (Prevention and Control of Pollution) Act and The Air (Prevention and Control of Pollution) Act require action to be taken over such matters, the government has mostly remained silent, while its departments have been passing the buck around. The National Green Tribunal has issued notices to all the agencies involved. Long before it began its slow and painful death, Bellandur Lake was part of a clever water and irrigation system devised by the founders of Bangalore in the 1600s, giving it the “city of lakes” moniker. The streams formed at the top of surrounding valleys were dammed into man-made lakes by constructing bunds. Each of these lakes would harvest rainwater from its catchments and the surplus would flow downstream, spilling into the next lake in the cascade via storm water drains or raja kaluves. The bodies of water would in turn serve the needs of the population. In the 1970s, there were still 285 lakes in the city, making it self-sufficient in its water needs. Today, however, there are just 194 lakes, and the large majority of them are sewage-fed. The rest have been lost to encroachments – by the Bangalore Development Authority, private real estate developers and illegal builders – to cater to the booming housing needs of a city of 10 million. Bangalore has been subject to unchecked urbanisation in the wake of the IT sector-fuelled economic boom of the late 1990s. The many software companies that sprung up during the dotcom boom attracted hundreds of thousands of skilled IT professionals from across the country, with thousands more people moving from villages and small towns to the city in search of work. According to studies by the IISc, rapid urbanisation and expansion between 1973 and 2016 caused a 1005% increase in paved surfaces and decline of 88% in the city’s vegetation, while water bodies declined by 85% between 2000 and 2014. The rise of the IT sector has also created the problem of e-waste in the city: a 2013 report estimated that Bangalore produces 20,000 tonnes of e-waste per year. Although a formal recycling system for e-waste was set up, 90% of it is dealt with through the informal sector, which is harder to monitor. Unaware of the necessary safety measures, some incinerate the e-waste, releasing lead, mercury and other toxins into the air – and dump the rest, allowing pollutants to infiltrate the groundwater. If one lake habitually catches fire, then another throws up thousands of dead fish every other summer. Ulsoor Lake, which doubles up as a picnic spot with boat rides and snack vendors on its banks, saw dead fish floating on its waters last year owing to the pollution caused by untreated sewage and consequent depletion of dissolved oxygen. The water pollution in Bangalore poses a serious threat to residents’ health and creates a chronic shortage of clean water for people to use. All in all, experts predict a severe water crisis which will make Bangalore uninhabitable by 2025, with residents potentially having to be evacuated. In the aftermath of the latest fire, I spoke to Aaditya Sood, an IT professional who watched the flames from his 10th floor balcony. He said he had seen the lake being “choked” in the seven or eight years he has lived there. “I have two kids and respiratory issues are a problem,” he says. The toxins from the lake get into the air, according to Ramachandra, noting that the cases of lung-related medical conditions have increased drastically in the city recently. Another resident, Vandana Sinha, who works for a consultancy firm, says the smoke from the fire almost immediately caused itchiness at the base of her throat. She had heard that seven to eight trucks worth of garbage was being dumped into the lake every night, adding to the lethal combination of pollutants in the waters. Report after report by expert committees have recommended several short and long term measures for rescuing the city’s lakes. Stopping the dumping of garbage, treating sewage water before it is allowed into the lakes, checking encroachments and slowing the development agenda are top of the list. In the next three years, if the same rate of development continues, the built up area in Bangalore is expected to increase from 77% to 93%, with a vegetation cover of a mere 3%. Ramachandra is determined to get the bureaucracy to act before it is too late. While the city may not fully cease to exist, without drastic improvement the other possibilities still sound impossibly grim. Follow Guardian Cities on Twitter and Facebook to join the discussion, and explore our archive here

Aithal B.H.,Energy and Wetlands Research Group | Aithal B.H.,Center for Sustainable Technologies Astra | Vinay S.,Energy and Wetlands Research Group | Venugopal Rao K.,Indian National Remote Sensing Centre | And 3 more authors.
11th IEEE India Conference: Emerging Trends and Innovation in Technology, INDICON 2014 | Year: 2015

The potential of Markov chain and cellular automata model with help of agents that play a vital role in a cities urbanisation through fuzziness in the data and hierarchal weights (for principal agents) have been used to understand and predict the urban growth for the Pune city, India. The model utilizes temporal land use changes with probable growth agents such as roads drainage networks, railway connectivity, slope, bus network, industrial establishments, educational network etc., to simulate the growth of Pune for 2025 using two scenarios of development - implementation of City Development Plan (CDP) and without CDP. In the study, multi temporal land use datasets, derived from remotely-sensed images of 1992, 2000, 2010 and 2013, were used for simulation and validation. Prediction reveals that future urban expansion would be in northwest and southeast regions with intensification near the central business district. This approach provides insights to urban growth dynamics required for city planning and management. © 2014 IEEE.

Ramachandra T.V.,Energy and Wetlands Research Group | Ramachandra T.V.,Center for Sustainable Technologies Astra | Ramachandra T.V.,Indian Institute of Science | Aithal B.H.,Energy and Wetlands Research Group | And 2 more authors.
Renewable and Sustainable Energy Reviews | Year: 2015

Concentration of greenhouse gases (GHG) in the atmosphere has been increasing rapidly during the last century due to ever increasing anthropogenic activities resulting in significant increases in the temperature of the Earth causing global warming. Major sources of GHG are forests (due to human induced land cover changes leading to deforestation), power generation (burning of fossil fuels), transportation (burning fossil fuel), agriculture (livestock, farming, rice cultivation and burning of crop residues), water bodies (wetlands), industry and urban activities (building, construction, transport, solid and liquid waste). Aggregation of GHG (CO2 and non-CO2 gases), in terms of Carbon dioxide equivalent (CO2e), indicate the GHG footprint. GHG footprint is thus a measure of the impact of human activities on the environment in terms of the amount of greenhouse gases produced. This study focuses on accounting of the amount of three important greenhouses gases namely carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) and thereby developing GHG footprint of the major cities in India. National GHG inventories have been used for quantification of sector-wise greenhouse gas emissions. Country specific emission factors are used where all the emission factors are available. Default emission factors from IPCC guidelines are used when there are no country specific emission factors. Emission of each greenhouse gas is estimated by multiplying fuel consumption by the corresponding emission factor. The current study estimates GHG footprint or GHG emissions (in terms of CO2 equivalent) for Indian major cities and explores the linkages with the population and GDP. GHG footprint (Aggregation of Carbon dioxide equivalent emissions of GHG's) of Delhi, Greater Mumbai, Kolkata, Chennai, Greater Bangalore, Hyderabad and Ahmedabad are found to be 38,633.2 Gg, 22,783.08 Gg, 14,812.10 Gg, 22,090.55 Gg, 19,796.5 Gg, 13,734.59 Gg and 91,24.45 Gg CO2 eq., respectively. The major contributors sectors are transportation sector (contributing 32%, 17.4%, 13.3%, 19.5%, 43.5%, 56.86% and 25%), domestic sector (contributing 30.26%, 37.2%, 42.78%, 39%, 21.6%, 17.05% and 27.9%) and industrial sector (contributing 7.9%, 7.9%, 17.66%, 20.25%, 12.31%, 11.38% and 22.41%) of the total emissions in Delhi, Greater Mumbai, Kolkata, Chennai, Greater Bangalore, Hyderabad and Ahmedabad, respectively. Chennai emits 4.79 t of CO2 equivalent emissions per capita, the highest among all the cities followed by Kolkata which emits 3.29 t of CO2 equivalent emissions per capita. Also Chennai emits the highest CO2 equivalent emissions per GDP (2.55 t CO2 eq./Lakh Rs.) followed by Greater Bangalore which emits 2.18 t CO2 eq./Lakh Rs. © 2015 Elsevier Ltd. All rights reserved.

Kumar U.,Energy and Wetlands Research Group | Kumar U.,Indian Institute of Science | Kumar U.,International Institute of Information Technology Bangalore | Mukhopadhyay C.,Indian Institute of Science | And 3 more authors.
Boletin Geologico y Minero | Year: 2014

Many regional environmental problems are the consequence of anthropogenic activities involving land cover changes. Temporal land cover data with social aspects are critical in tracing relationships of cause and effect on variables of interest with the effects of context on behaviour, or with the process of human environmental interaction and are also useful for the governance of urbanising cities. Many cities are now rapidly becoming urbanised and undergoing redevelopment for economic purposes with new roads, infrastructure improvements, etc. raising the necessity to understand the dynamics of the urban growth process for the planning of natural resources. Cellular automata (CA), an artificial intelligence technique based on pixels, states, neighbourhoods and transition rules is useful in modelling the urban growth process due to its ability to ft such complex spatial nature, using simple and effective rules. This study develops the calibration of a CA model by taking into account spatial and temporal dynamics of urban growth. The effectiveness of this technique is demonstrated by capturing the growth pattern of Bangalore, a city in India, with historical remote sensing and population data. © 2014 Instituto Geologico y Minero de Espana. All Rights reserved.

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