• Energy Research

Abstract This study investigates the possibility of using and developing hydrokinetic power to supply reliable, affordable and sustainable electricity to rural, remote and isolated loads in rural South Africa where reasonable water resource is available. Simulations are performed using the Hybrid Optimization Model for Electric Renewable (HOMER) and the results are compared to those from other supply options such as standalone Photovoltaic system (PV), wind, diesel generator (DG) and grid extension. Finally the paper points out some major challenges that are facing the development of this technology in South Africa.

A field experiment was conducted during 1993–1995 to study the effect of industrial effluent on the initial growth of Azadirachta indica A. Juss. (Neem) in arid region. The effluent released from textile industry had high pH, EC, SAR and RSC. Various treatments were: irrigation with effluent only (W1), effluent mixed with canal water at 1:1 ratio (W2), gypsum‐treated effluent (W3), gypsum‐treated soil (W4) and wood ash‐treated soil (W5). W5 was the best treatment where neem attained 218 cm height, 118 cm crown diameter and 11.2 cm collar circumference at 28 months of age; followed by W1 treatment, where trees were on an average 186 cm tall and had 104 cm crown diameter and 9.4 cm collar circumference. Growth of the seedlings was the poorest in W2treatment. Increase in biomass accumulation over W2 treatment (1.89 kg tree−1) was 3.6 fold in W5, 2.1 fold in W1, 2.0 fold in W4 and 1.4 fold in W3 treatments. Though effluent application increased soil organic matter, electrical conductivity and in some cases pH also, but gypsum‐ and wood ash‐ treated soil ameliorated the pH by 0.25 units in comparison to the initial data. These results suggest that industrial wastewater can be effectively used to boost up establishment and growth of Neem (Azadirachta indica) in arid zone. Addition of wood ash improves the rate of growth. Irrigation with industrial effluent caused slight increase in electrical conductivity and decline in the soil pH. Santrauka Eksperimentas vyko 1993–1995 m. siekiant ištirti pramoninių nuotekų poveikį Azadirachta indica A. Juss. (Neem) sodinukų augimo pradžiai sausringuose regionuose. Tekstilės pramonės išleidžiamų nuotekų didelės pH rodiklio reikšmės, elektrinis laidumas, natrio adsorbcijos santykis ir natrio karbonato liekana. Tiriant taikyti įvairūs dirvožemio apdorojimo būdai: drėkinta tik nuotekomis (W1 ), nuotekos maišytos su kanalo vandeniu santykiu 1:1 (W2 ), nuotekos veiktos gipsu (W3 ), į dirvožemį dėta gipso (W4 ) ir dirvožemis tręštas medienos pelenais (W5 ). Efektyviausias buvo W5 apdorojimo būdas. 28 mėnesių augalai siekė 218 cm aukštį, jų vainiko skersmuo buvo 118 cm, žiedo perimetras – 11,2 cm. Stebint W1 apdorojimo tipą, medžiai buvo vidutiniškai 186 cm aukščio, vainikas – 104 cm skersmens, žiedai 9,4 cm perimetro. Blogiausiai sodinukai augo apdorojant W2 būdu. Nors naudojant nuotekas dirvožemio organinių medžiagų kiekis, elektrinis savitasis laidumas ir kai kuriais atvejais pH reikšmė padidėjo, tačiau gipsu ir medienos pelenais apdorotame dirvožemyje pH padidėjo per 0,25 vienetus, palyginti su pirminiais duomenimis. Šie rezultatai rodo, kad pramoninės nuotekos gali būti efektyviai naudojamos Neem (Azadirachta indica) želdinti ir auginti sausose teritorijose. Medienos pelenai pagerino augimo spartą. Drėkinimas pramoninėmis nuotekomis lėmė nežymų elektrinio savitojo laidumo augimą ir dirvožemio pH sumažėjimą. Резюме Экспериментальное поле возделывалось в 1993–1995 гг. с целью изучить воздействие промышленных стоков на начало роста Azadirachta indica A. Juss. (Neem) в засушливых районах. В стоках от производства текстиля высоко значение pH, электропроводимость, соотношение адсорбции натрия и остаток карбоната натрия. Применялись разные способы обработки почвы: орошение только стоками (W1 ); смесью стоков с водой из канала в соотношении 1:1 (W2 ); стоками, обработанными гипсом (W3 ); обработка почвы гипсом (W4 ) и удобрение древесной золой (W5 ). Наиболее эффективным способом оказалась обработка древесной золой. Высота растений в возрасте 28 месяцев составляла 218 см, венчик в поперечнике – 118 см, цветок – 11,2 см. После обработки почвы по типу W1 растения достигали 186 см в высоту, венчик в поперечнике – 104 см, цветок – 9,4 см. Наименее эффективным для растений способом оказалась обработка почвы по типу W2 . Несмотря на то, что при применении стоков количество органических веществ в почве, электропроводимость и в некоторых случаях значение pH увеличилось, однако при обработке почвы гипсом и древесной золой pH увеличилось более чем на 0,25 единиц по сравнению с начальными данными. Эти результаты показали, что промышленные стоки могут эффективно применяться для озеленения и выращивания Neem (Azadirachta indica) на засушливых территориях. Древесная зола ускоряла рост растений. Орошение промышленными стоками способствовало незначительному увеличению электропроводимости и уменьшению в почве pH.

In this paper, we compare 2015 satellite-derived natural gas (gas) flaring data with the greenhouse gas reduction targets presented by those countries in their nationally determined contributions (NDC) under the United Nations Framework Convention on Climate Change (UNFCCC) Paris Agreement. Converting from flaring to utilization is an attractive option for reducing emissions. The analysis rates the potential role of reduction of gas flaring in meeting country-specific NDC targets. The analysis includes three categories of flaring: upstream in oil and gas production areas, downstream at refineries and transport facilities, and industrial (e.g., coal mines, landfills, water treatment plants, etc.). Upstream flaring dominates with 90.6% of all flaring. Global flaring represents less than 2% of the NDC reduction target. However, most gas flaring is concentrated in a limited set of countries, leaving the possibility that flaring reduction could contribute a sizeable portion of the NDC targets for specific countries. States that could fully meet their NDC targets through gas flaring reductions include: Yemen (240%), Algeria (197%), and Iraq (136%). Countries which could meet a substantial portion of their NDC targets with gas flaring reductions include: Gabon (94%), Algeria (48%), Venezuela (47%), Iran (34%), and Sudan (33%). On the other hand, several countries with large flared gas volumes could only meet a small portion of their NDC targets from gas flaring reductions, including the Russian Federation (2.4%) and the USA (0.1%). These findings may be useful in guiding national level efforts to meet NDC greenhouse gas reduction targets. Keywords: VIIRS, Gas flaring, Nightfire, Nationally determined contributions, UN climate agreement

Fuel-flexible solid oxide fuel cell (SOFC) technologies are presently under study in a Vietnam-Japan international joint research project. The purpose of this project is to develop and demonstrate an SOFC-incorporated energy circulation system for the sustainable development of the Mekong Delta region. Lab-scale methane fermentation experiments in this study with a mixture of biomass feedstock collected in the Mekong Delta (shrimp pond sludge, bagasse, and molasses from sugar production) recorded biogas production yield over 400 L kgVS−1 with H2S concentration below 50 ppm level. This real biogas was directly supplied to an SOFC without any fuel processing such as desulfurization, methane enrichment and pre-reforming, and stable power generation was achieved by applying paper-structured catalyst (PSC) technology.

Poria cocos (Schw.) Wolf, an important medicinal and food fungus, is well known in East Asia. Due to growing market demand, long cultivation period, and consumption of pine trunk during cultivation, developing alternative methods for producing P. cocos and/or its active components is of interest. In the present study, the effects of different culture methods on biomass and accumulation of four triterpenoids were investigated. The ethanol extract of fermented mycelium (EFM) was orally administered to rats. Urine output and concentrations of electrolytes (Na+, K+, and Cl-) were measured. Our results showed that mycelia grew better under continuous shaking culture condition (7.5 g DW·L-1), and higher triterpenoid levels were accumulated in two-stage culture (112 mg·L-1, 2.03%). The optimal starting time of static culture for triterpenoid yield was 4th d after shaking culture. Single administration of middle and high dose of EFM significantly increased urine output, Na+ and Cl- excretion, and Na+/K+ ratio. These results suggested that ethanol extract of cultured mycelia showed significant diuretic activity in rats and two-stage culture of P. cocos could be an alternative way to produce mycelia and triterpenoids.

Land use changes from cropland to orchards in Eastern China have raised serious concerns about the regional nitrogen (N) cycle and greenhouse gas balance. We measured soil nitrous oxide (N2O) emissions and methane (CH4) uptake using manual static chambers in an apple orchard. The primary aims were to assess the effect of N fertilizer application on gas fluxes and quantify the site-specific N2O emission factor (EFd). Field experiments were arranged in a randomized block design with three N input rates (0, 800 and 2600/2000 kg N ha−1 year−1). We found that orchard soils were a negligible CH4 sink (−1.1 to −0.4 kg C ha−1 year−1). Annual N2O emissions responded positively to N input rates, ranging from 34.1 to 60.3 kg N ha−1 year−1. EFd ranged from 1.00% to 1.65% with a mean of 1.34%. The extremely large background emissions of N2O (34.1–34.3 kg N ha−1 year−1) most likely originated from nitrate accumulation in the soil profile because of historical overuse of N fertilizer. We conclude that (1) site-specific EFd is suitable for assessing regional direct N2O emissions from upland orchards; and (2) conventional fertilization regimes must be avoided, and reduced N input rates are recommended in the study region.

<p>Adaptation to actual climate change and contingency planning to reduce vulnerability from likely climate change effects is crucial for the New Zealand dairy industry. Thus in alignment with international treaties and growing international pressure and speculation, the New Zealand Government in October 2007 announced an Emissions Trading Scheme (ETS) adaptable specifically to the New Zealand scene. This ETS passed into law in September 2008 through the enactment of the Climate Change Response (Emissions Trading) Amendment Act 2008. This thesis specifically looks at agriculture related emissions and calculates the liability faced by the dairy industry come 2013 when the industry is completely involved in the ETS. The purpose of this is to further aid the industry so that it can best align itself with the ETS in order to minimise this liability. This is not simply an aid to help the industry save money, as the minimisation of liability should come as a benefit to the environment through reduced emissions. There is also a second issue associated with this - as to whether the liability faced by the industry will be material enough in order for the farmers to actually mitigate their environmental impacts or will they simply bear the expense and ignore the opportunities to reduce their emissions against a baseline (and potentially generate carbon credits for sale) and/or offset any residual emissions through purchasing carbon credits? This therefore analysed the threshold of farmer's incomes whereby they will choose to abate their emissions rather than simply paying for their carbon emissions liability. This threshold obviously varied greatly through the dairying industry with differing factors - this was taken into account and discussed in detail. Other aspects influence this threshold also, factors such as the opportunity for the industry to market a niche product if they do achieve a low carbon or carbon neutral status for their products, cost competitiveness of available abatement technologies, geographical issues pertaining to each abatement method and so on. In order to gain an insight into farmers' perceptions 23 Taranaki dairy farmers were interviewed. This 23 was selected randomly from a list of farmers who reside in the geographical area of Taranaki. This randomisation allowed for an analysis of a variety of size of farmers which eliminated a bias of perceptions from dominating farming sizes within this region. Utilising the theoretical framework surrounding stabilisation triangles, riparian management and nitrification inhibitors were the basis of this examination for emissions reduction management due to their major co-benefit of improved water quality alongside the ultimate goal of emissions reductions. The extent of potential mitigation through the implementation of riparian management and nitrification inhibitors equates to two of the wedges required for the overall reduction in emissions under the ETS. Also, as explained earlier, the co-benefit of improved water quality associated with riparian management and nitrification inhibitors make their implementation even more attractive. The theory behind riparian management and nitrification inhibitors has mostly been done, therefore for the purpose of this thesis, farmers' perceptions of the abatement options were examined. These perceptions included the associated opportunities as well as the challenges that will be faced by those participating farmers.</p>