Abstract

A preliminary study of the feasibility of using existing drinking water supply systems to provide hot water for heating purposes to a typical 140-home subdivision has been undertaken. This preliminary study has centered on (i) types of municipal water system designs and effects of system design upon heating use; (ii) methods of using low-to-moderate temperature water for heating purposes and possible institutional barriers; (iii) identification and description of a typical residential community suitable for hot water heating; (iv) evaluation of thermal losses in the uninsulated main distribution system from the main pumping station having assumed geothermal heating to the subdivision; (v) evaluation of thermal losses in the uninsulated street mains in the subdivision; (vi) estimation of size and cost of the pumping station main heat exchanger to supply geothermal energy to the drinking water; (vii) sizing of individual house heat exchangers; (viii) pumping and power requirements to supply the increased water flow rate through the subdivision street water distribution lines; and (ix) pumping and piping requirements to provide heating water flow from the street lines to a typical residence. From the results obtained thus far, it would appear that the use of existing uninsulated water supply systems will be advantageous more » in many communities having nearby low-to-moderate temperature geothermal resources. « le Document type: Report

Abstract

Governments worldwide face the difficult challenge of deciding which infrastructure projects to prioritize and select for implementation, given the limits of available funding and the need to attain their developmental goals. The key objective of this report is to conduct a comparative exercise between the World Bank's Infrastructure Prioritization Framework, a multicriteria analysis–based methodology to project prioritization, and a more complex cost-benefit analysis–based approach. The report focuses on Chile, which has a well-institutionalized evaluation process that uses cost-benefit analysis to assess projects on their quality and ability to generate value for money. The analysis compares the results of the Infrastructure Prioritization Framework alongside Chile's current cost-benefit analysis–based and multicriteria analysis approaches to the same subsets of projects in the road transport and water reservoir subsectors, respectively. The results show that the Infrastructure Prioritization Framework has application beyond its original proposition and can complement a traditional cost-benefit analysis by directly considering social and environmental policy goals that are otherwise difficult to quantify in a cost-benefit analysis. The analysis also finds that in Chile there is a discrepancy between the stated goals and objectives of the appraisal system and the actual implementation. In the case of transport sector projects, there is an evident deviation between cost-benefit analysis–based selection policy and actual decisions made for project implementation. In the case of water catchment selection, there is a bias toward projects with higher financial-economic performance as compared to social-environmental performance, despite policy intentions to afford consideration to environmental and social development goals. Document type: Book

Abstract

In the recent years various Demand Side Management (DSM) projects were successfully completed on Department of Water Affairs (DWA) pump schemes. Each pump scheme consists of a number of pump stations which transfer water to power stations in the Mpumalanga Highveld area and municipal off-takes. The pump stations in a scheme are interconnected via rivers and pipe lines in order to transfer water from national key-point dams to different water users. Therefore, to manage the Highveld's water balance, all the interconnecting schemes work together to keep the important dams at a maximum operating level. Introducing load management on these sites, local- and regional strategies were developed and rolled out. Local strategies involve upgrades to existing pump stations, while regional strategies involve the interactions of the different pump schemes. With the completion of the local strategies, regional strategies for combined water balance and energy optimisation can be developed. By building a system that is more `visible', data is automatically collected. This will then be used to develop an advanced management strategy for the DWA. Therefore, in this article an overview is given on completed load management projects, planned future projects and the strategy to develop a combined electricity and water supply strategy for the DWA http://www.ieee.org/conferences_events/conferences/xplore_conference_proceedings.html

Abstract

Design of modern water supply systems of large cities as well as their management via renovation of hydraulic models poses time-consuming tasks to researchers, and coping with this task requires specific approaches. When tackling these tasks, water services companies come across a lot of information about various objects of water infrastructure, the majority of which is located underground. In those cases, modern computer-aided design systems containing various components come to help. These systems help to solve a wide array of problems using existing information regarding pipelines, analysis and optimization of their basic parameters. CAD software is becoming an integral part of water supply systems management in large cities, and its capabilities allow engineering and operating companies to not only collect all the necessary data concerning water supply systems in any given city, but also to conduct research aimed at improving various parameters of these systems, including optimization of their hydraulic properties which directly determine the quality of water. This paper contains the analysis of automated CAD software for hydraulic design and management of city water supply systems in order to provide safe and efficient operation of these water supply systems. Authors select the most suitable software that might be used to provide hydraulic compatibility of old and new sections of water supply ring mains after selective or continuous draw-in renovation and decrease in diameter of distribution networks against the background of water consumption decrease in the cities. Document type: Article

Abstract

In the early 20th century, rapid industrial growth around the world enabled the development of many advanced mechanical structures. Some of these structures were successfully used to improve agricultural efficiency or increase people’s comfort. Such a situation was observed in 1910 in the western part of Poland, which at the time was partitioned by Habsburg Austria, the Kingdom of Prussia, and the Russian Empire. In the city of Poznan, a Polish landlord built an advanced structure to automate his farming, using freely available wind energy. At first glance, it was a classic windmill, with a multi-blade wind turbine fixed to the top of a cylindrical masonry tower. However, some additional elements demonstrate the uniqueness of such a structure at the time. One hundred years later, the structure is located at the centre of a rapidly growing area of the city. For that reason, restoration of the tower is complex and requires the reconstruction of damaged or missing elements while observing new safety regulations. In this work, the author presents the basic assumptions necessary for the future renovation process.