Scielo RSS <![CDATA[Journal of Energy in Southern Africa]]> http://www.scielo.org.za/rss.php?pid=1021-447X20100003&lang=es vol. 21 num. 3 lang. es <![CDATA[SciELO Logo]]> http://www.scielo.org.za/img/en/fbpelogp.gif http://www.scielo.org.za <![CDATA[<b>Electrical performance results of an energy efficient building with an integrated photovoltaic system</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1021-447X2010000300001&lng=es&nrm=iso&tlng=es A 3.8 kW rooftop photovoltaic generator has been installed on an energy efficient house built at the University of Fort Hare, Alice campus, South Africa. The system, located on the north facing roof, started generating electrical power in February 2009. In addition to providing electrical energy, the photovoltaic panels also act as the building roofing material. An instrumentation and data acquisition system was installed to record the indoor and outdoor ambient temperature, indoor and outdoor relative humidity, wind speed and direction, solar irradi-ance, electrical energy produced by the solar panels and the household energy consumption. This paper presents the initial results of the electrical performance of the building integrated photovoltaics (BIPV) generator and energy consumption patterns in the energy efficient house. <![CDATA[<b>Heat recovery in the textile dyeing and finishing industry: Lessons from developing economies</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1021-447X2010000300002&lng=es&nrm=iso&tlng=es Many developing countries, including African ones, look forward to developing strong integrated textile industries to add value to already-available raw materials. Dyeing and finishing activities are, however, energy-intensive. In many cases, these depend on imported fossil fuels. By turning to heat recovery, significant cost savings can be achieved improving profitability and competitiveness. The techniques and technologies of heat recovery from waste water and exhaust air are analysed. Experiences prove that in most cases heat recovery requires low investment and has a low payback of normally less than 2 years. The case of the Mauritian dyeing and finishing industry is highlighted, including the possible use of a low-cost heat recovery unit made from indigenous resources. <![CDATA[<b>Comparison between two different solution-pumping methods in absorption refrigeration machines</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1021-447X2010000300003&lng=es&nrm=iso&tlng=es This paper presents a pumping method in absorption refrigeration where a vapour-driven pump is to replace the electricity-driven pump. The vapour pump is driven by a fraction of the generator's hot, high-pressure, vapour mixture. The refrigerator is thus exclusively heat-powered and rendered independent of the availability of electricity as the main energy source. The design and operation of the vapour pump is presented. The results obtained by a computer simulation program show a decrease in performance (COP), which is confirmed by the data obtained from a 1 kW cooling capacity refrigerator. Peak performances occur at higher generator temperatures when compared to a cycle using an electricity-driven pump.