Raising Energy Efficiency of High-Head Drinking Water Pumping Schemes in Hilly India – Massive Potential, Complex Challenges

Investigations of energy efficiency of 25 pumps showed wire-to-water efficiencies ranging from 30% to 60%, with an average of 47%. Raising the efficiency of just 7 pumps to the realistic target of 60% would require an initial investment of 126 k€ and represent a net present value (profit) of 446 k€ over a 10-year pump lifetime, saving 8.6 kt of CO2 emissions. The primary measures for raising efficiency are in order of priority: 1) improving pre-filtration of raw water to prevent rapid mechanical wear due to suspended particles during monsoon, 2) providing training, improved working conditions, and better tools and spare parts among pump operators and 3) replacing aging, oversized pumps with properly sized pumps operating close to peak efficiency. As of January 2014 the results have been confirmed by a Bureau of Energy Efficiency-certified energy auditor and the extent and funding of efficiency measures implementation is in planning

Fate of gasoline oxygenates in conventional and multilevel wells of a contaminated groundwater table in Düsseldorf, Germany

11 pages, 5 figures, 5 tables.-- PMID: 16398114 [PubMed].-- Printed version published Nov 2005.In a gasoline-contaminated site in Düsseldorf, Germany a two-year monitoring program was carried out to determine the presence, behavior, and fate of 12 gasoline additives in a total of 96 samples from 14 groundwater wells. The origin of contamination was suspected to be a gasoline spill at a gas station. Target compounds were methyl-tert-butyl ether (MTBE), its main degradation products, tert-butyl alcohol (TBA) and tert-butyl formate (TBF); other gasoline additives, oxygenate dialkyl ethers: Ethyl-tert-butyl ether (ETBE), tert-amyl methyl ether (TAME) and diisopropyl ether (DIPE); aromatics: Benzene, toluene, ethylbenzene and xylenes (BTEX), and other compounds causing odor problems: Dicyclopentadiene and trichloroethylene. Purge and trap coupled with gas chromatography-mass spectrometry permitted detection of ng/L concentrations. Ninety of the 96 samples analyzed contained MTBE at levels varying between 0.01 to 645 μg/L. Five contaminated hot spots were identified with levels up to U.S. Environmental Protection Agency (U.S. EPA) drinking water advisory values (20–40 μg/L) and one of them doubling Danish suggested toxicity level of 350 μg/L at a depth of 11 m. No significant natural attenuation was found in MTBE degradation, although samples with high levels of MTBE contained 0.1 to 440 μg/L of TBA. These levels were attributed to its presence in the contamination source more than MTBE degradation. tert-Butyl alcohol was found to be recalcitrant in groundwater. In all cases, BTEX were at low concentrations or not detected, showing less persistence than MTBE. The monitoring of the contamination plume showed that the distribution of the MTBE and TBA in the aquifer formed a similar vertical concentration profile that was influenced by the groundwater flow direction.This research was part of the WATCH (EVK1-CT-2000-00059) European Union project that was funded by the European Union Environment and Sustainable Development subprogram and from the Ministerio de Ciencia y Tecnología (REN2001-5039-E).Peer reviewe