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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Dear Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>You say “</span><span lang=EN-CA>A good kerosene stove is going to be above 45-50% efficient</span><span style='color:#1F497D'>.” I have yet to find one doing above 42%, and a good average value was 35%. The better ones were pressure stoves; wick stoves were invariably poorer. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>The interesting question is where all the losses come from. In the wick stove it is outward radiation from the heater, which glows red-hot in operation to provide the energy to evaporate the kerosene from the wick. But the loss of efficiency in the pressure stoves really puzzles me.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Prof Philip Lloyd</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Energy Institute</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Cape Peninsula University of Technology</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>PO Box 652, Cape Town 8000</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Tel:021 460 4216</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Fax:021 460 3828</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Cell: 083 441 5247</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Crispin Pemberton-Pigott<br><b>Sent:</b> 30 July 2015 10:23<br><b>To:</b> Stoves<br><b>Subject:</b> [Stoves] New document from ESMAP<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='background:white'><span lang=EN-CA>Dear Friends of Big Reports<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span lang=EN-CA>There is a document you can get at <o:p></o:p></span></p><p class=MsoNormal style='background:white'><span lang=EN-CA style='font-family:"helvetica neue";color:black'><a href="https://openknowledge.worldbank.org/bitstream/handle/10986/21878/96499.pdf?sequence=1">https://openknowledge.worldbank.org/bitstream/handle/10986/21878/96499.pdf?sequence=1</a><o:p></o:p></span></p><p class=MsoNormal style='background:white'><span lang=EN-CA style='font-family:"helvetica neue";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>which is from ESMAP<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>It makes for very interesting reading, from great observations to howlers. It appears to have been written mostly by policy makers but makes many technical claims as well.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Some points are really worth debating here:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.5pt;font-family:"Arial","sans-serif"'>“LPG is a clean, non-toxic fuel that emits little particulate matter and burns efficiently. Compared <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.5pt;font-family:"Arial","sans-serif"'>to kerosene, it delivers double the heat for the same quantity used.”<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.5pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Which quantity would that be? Certainly not per $. Mass? LPG has about the same energy content per kg as kerosene so this claim surprised me. A good kerosene stove is going to be above 45-50% efficient, fuel heat to pot heat. LPG is about 65% efficient on a good day. I would say that is 30-45% better.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Maybe they meant LPG with a modern good condition burner compared with an old wick stove. In that case if could be more than double. If we compare really good kerosene stoves with LPG there is no difference. Peak efficiency at, say, 1.25 kW is comparable though I have seen a cheap wick stove from China that outperformed a new LPG stove at that power level (71% v.s. 65%).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Why is anyone so certain kerosene is such a bad fuel? Is it perhaps bad stoves that cause the problem? The long term answer is low pressure stoves because they avoid all sorts of pressure-related problems and does away with wicks at the same time (they lose effectiveness over time). We need some new inventions.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>One of the objections raise against kerosene compared with LPG in South Africa was from the fuels industry. With LPG they control the distribution right to the last mile. With kerosene, all sorts of people are involved in micro trading fuel in plastic bags (!) and bottles.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Unlicensed people! Ordinary folks! <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Anyway, have fun reading. There are contributions from all the usual suspects. There are lots of great charts you can cite.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA>Crispin<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>PS I see they once again have omitted the stellar performance of the super-clean TLUD coal stoves rolled out in Ulaanbaatar, the most expensive and most successful externally funded stove project ever. It is also the first time a city’s air pollution has been substantially improved (-63%) without changing the fuel. Eat <i>that</i>, London…<o:p></o:p></span></p></div><div style="position:absolute;margin:15px 0 0 0px; padding-top:10px;padding-right:15px;min-width:350px; border-top:1px solid #ccc;font-size:12px; color: #333; font-family:arial,'Hiragino Sans GB',Tahoma,Helvetica,STHeiti; ">This email has been protected by YAC (Yet Another Cleaner) <a href="http://www.yac.mx?source=email" style="display:block;padding-top:5px; color:#2bafed;text-decoration:none;">www.yac.mx</a></div></body></html>