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[en] This letter reports on the design and pilot installation of GridShares, devices intended to alleviate brownouts caused by peak power use on isolated, village-scale mini-grids. A team consisting of the authors and partner organizations designed, built and field-tested GridShares in the village of Rukubji, Bhutan. The GridShare takes an innovative approach to reducing brownouts by using a low cost device that communicates the state of the grid to its users and regulates usage before severe brownouts occur. This demand-side solution encourages users to distribute the use of large appliances more evenly throughout the day, allowing power-limited systems to provide reliable, long-term renewable electricity to these communities. In the summer of 2011, GridShares were installed in every household and business connected to the Rukubji micro-hydro mini-grid, which serves approximately 90 households with a 40 kW nominal capacity micro-hydro system. The installation was accompanied by an extensive education program. Following the installation of the GridShares, the occurrence and average length of severe brownouts, which had been caused primarily by the use of electric cooking appliances during meal preparation, decreased by over 92%. Additionally, the majority of residents surveyed stated that now they are more certain that their rice will cook well and that they would recommend installing GridShares in other villages facing similar problems. (letter)
[en] On 21st September 2009 an earthquake of magnitude (Mw 6.1) occurred in the East Bhutan. This earthquake caused serious damage to the residential area and was widely felt in the Bhutan Himalaya and its adjoining area. We estimated the source model of this earthquake using modified semi empirical technique. In the rupture plane, several locations of nucleation point have been considered and finalised based on the minimum root mean square error of waveform comparison. In the present work observed and simulated waveforms has been compared at all the eight stations. Comparison of horizontal components of actual and simulated records at these stations confirms the estimated parameters of final rupture model and efficacy of the modified semi-empirical technique (Joshi et al., Nat Hazards 64:1029–1054, 2012b) of strong ground motion simulation.
[en] It seems the uranium potential of Bhutan is very poor, due to mainly the tectonic patter of the region. However, some favourable conditions for finding small uranium deposits exist. The Pliestocen Siwalik formation is fluvitile, carbonaceous bearing sandstone. In Bhutan it is presented as a thin sequence or is absent, but in nearby Pakistan it hosts small uranium deposits. Copper occurrences are reported by Ganseer in this formation and it could supposed that they are associated by uranium mineralization. All the river draining the Himalayas have placer of uranothorium minerals. There may be localities in the southern parts of Tibet Massif disemenations of these minerals are found to be exploitable. The speculative uranium potential is less than 1000 tons
[en] In Nepal, data from 49 surveillance stations show that there has been a distinct temperature increase since the middle of the 1970s, the greatest changes being on the highest summits. When lakes overfill and beaches threaten to break down, this is a result of the global warming that melts the glaciers. The glaciers in Bhutan are observed to decrease by 30 - 40 metres per year, in some years as much as 100 metres. In the village of Tribeni an advanced warning system has been established to warn the 10 000 inhabitants of a potential flood from Lake Tsho Rolpa 108 km upstream. Research from the Himalayas also point to another serious threat. The melting threatens not only human lives, tourism, foot paths, roads, bridges and power stations. Since the mountains are the water towers of the world, filling rivers and lakes with water upon which all life depends, continued shrinking of the world's glaciers as is now observed will cause many rivers and fresh-water systems to dry out. Researchers from the UN Unep programme and International Centre for Integrated Mountain Development have registered at least 44 glacier lakes that are increasing so fast that they may cause outburst floods within five years. Similar investigations are being planned in India, Pakistan and China
[en] Electric power has traditionally been classified as a non-traded good, produced and consumed within the country of origin. More recently, electricity has been traded across national borders and in certain cases, viz., Bhutan, has been the dominant export; in other situations, it is used to repay debts owed to neighboring countries. This paper investigates the role of electricity as the primary export, analyzes its valuation, and then goes on to evaluate the impact on the terms of trade. We conclude that in the medium-term, the electric power exporting economy would be better off developing its manufacturing sector to diversify its exposure and to protect its trade interests. The case of Bhutanese hydro-electricity exports to India is studied and the change in trade advantage with every increase in power tariff is ascertained. It is found that a 1.26% annual increase in (non-food) consumer prices is correlated with a 1% increase in electricity export tariff. While the causality from electric power tariff to Indian manufactures prices is not established statistically, a change in manufactures prices feeding back into consumer prices in Bhutan is statistically significant. Suggestions are offered for Bhutan to reduce dependence on Indian imports and to diversify its export market exposure. - Highlights: • Electricity as principal export of small economy. • Bilateral trade with large economy. • Tourism as major income generator for small economy. • Partial equilibrium model involving key variables. • Small economy would need to diversify. • Important subject for inter-temporal and inter-regional trade of power
[en] Agriculture communities in the Himalayas are disproportionately vulnerable due to the emerging challenges from climatic and non-climatic stressors. In this study, we systematically review peer-reviewed literature focused on vulnerability assessment of agriculture communities (n = 26) in the five Himalayan countries (Bhutan, China, India, Nepal, and Pakistan). We examine the yearly distribution, geographical scale, methodological approach, stress in consideration, indicators used, and assessment communication methods of the reviewed papers. Our findings indicate that vulnerability assessment of agriculture communities in the Himalayas is a recent practice, as all of the reviewed articles were published after 2007. About 62% of the assessments were conducted at local (household, community, and village) level, and few assessments at sub-national (19%) and basin (12%) levels. Indicator-based methods using primary quantitative data were most common (54%). Further, 90% of the studies addressed vulnerability to a single stressor with 50% of papers dealing with the vulnerability of agriculture communities to climate change and/or climate variability. From the analysis of the literature, it was found that multi-level, multi-stress, and comprehensive socio-ecological assessments were seldom attempted. Mostly the studies were done in isolated pockets and failed to identify the patterns of vulnerability. We advocate that to holistically understand the vulnerability-creating and differentiating mechanisms in agriculture communities, vulnerability assessment should adopt a multi-level approach by integrating both social and ecological determinants, firstly to identify the hotspots of vulnerability and then to deeply understand the root causes in the identified hotspots through integrated analysis.
[en] The paper reports on the renewable energy and solar electrification programmes in Bhutan. Findings from a field survey of PV systems have been presented and lessons identified. A discussion of the key results from the assessments are also presented and conclusions drawn. The paper provides direct feedback on the performance of PV systems in difficult geographical conditions such as those prevailing in Bhutan. The results and findings of this paper are relevant to PV industry targeting rural electrification markets and policy makers and aid-planners involved in PV rural electrification initiatives. (authors)
[en] Highlights: • TL response of natural white quartz collected from Gelephu, Bhutan was studied. • There was five trapping sites at depths ∼0.68, 0.90, 0.97, 1.06 and 1.10 eV. • The 426 K TL peak showed linear dose response from 10 mGy to 10 Gy. • The 426 K TL peak was found to fade very slowly. - Abstract: TL properties of natural quartz mineral collected from Gelephu, (Bhutan) were studied. With the help of various characterization techniques the quality of the sample was tested. The thermoluminescence (TL) analysis was carried out under X-ray irradiation. The un-irradiated sample showed no TL signal; however, after X-ray irradiation, a composite glow curve was observed. The kinetic analysis of the glow curve was carried out and it was observed that there was five trapping sites at depths ∼0.68, 0.90, 0.97, 1.06 and 1.10 eV responsible for five closely spaced glow peaks at ∼341, 362, 383, 397 and 426 K respectively. The dosimetric features of the mineral were studied. The response when studied from the whole glow curve was non-linear. However, the dose response studied from the 426 K peak was found to be linear from 10 mGy to 10 Gy. The fading of the TL signal of this 426 K peak was ∼12% within 5 days after irradiation and onward it was ∼4% up to 30 days. The reproducibility of the results was also good.
[en] The earthquake is known to be an unpredictable geophysical phenomenon. Only few seismic indicators and assumptions of earthquakes can be predicted with probable certainty. This study attempts to analyze the earthquakes over the Indo-Himalayan Border region including Bhutan, Bangladesh, Nepal, China and India during the period from 1995 to 2015. Bangladesh, Bhutan and China borders experience fewer earthquakes than Nepal and India border regions. However, Indo-China rim has inconsistency and vast range in its magnitude. Bangladesh though is a small country with respect to others, but it experiences earthquakes comparable to Bhutan. Nepal experiences highest number of earthquakes. In the last 20 years around 800 records have been observed with moment magnitude > 4.0 Richter scale, while very few records (around 10–12) have been observed for large earthquakes having moment magnitude > 6.0 Richter scale over the region. In this study adaptive neuro-fuzzy inference system has been implemented to assess the predictability of seismic moment associated with large earthquakes having the moment magnitude between 6.0 and 8.0 Richter scales using different combination of epochs, technique and membership functions. The Gaussian membership function with hybrid technique and 40 epochs is observed to be the reasonable model on the basis of the selected spatial and temporal scale. The forecast error in terms of root-mean-square error with the stopping criterion 0.001 has been observed to be 0.006 in case of large earthquakes (> 6.5 Richter scale), that is, forecast accuracy of 99.4%. The model bias of 0.6% may be due to inadequate number of large earthquakes having moment magnitude > 6.5 Richter scale over the region.
[en] Sikkim is a country in the eastern Himalayas and is bound on the west by Nepal, on the north by Tibet, on the east by Bhutan and on the south by India. Precambrian Darjeeling gneiss forms the rim of the amphitheatre while schists of Late Precambrian to Lower Paleozoic rocks form tee habital interior. A small outcrop of carboniferous to Permain methomorphic rocks is preserved in the Tista Basin as well in a thin outcrop trust upon fluvitile beds of Sivalik which is mostly of Pliestocene age. Imbricate thrusts have stacked the rocks in a vast heap where reverse metamorphism is common. Ni information is available concerning uranium occurrences and resources as well as past and present explorations. The uranium potential of Sikkim is almost zero