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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText><span lang=EN-US>Dear Paul<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-US>></span>Each household produces about 1/3 kg of biochar each day. If the biochar yield by weight of the raw fuel is 20%, the biomass needed is 1.66 kg per day. If 25%, then the biomass is only 1.33 kg/day.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><span style='color:black'>I am not completely clear on your calculation. Are you showing the amount of biomass input needed for a yield of 20 and 25%?<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText>>Less than 2 kg/day represents fuel savings compared with the inefficient 3-stone and other fires. AND they are getting the biochar. This correctly contradicts the people who say that making biochar leads to increased cutting of the forests. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I am not sure who says it leads to an increase, I do read a number of people <i>asking the question</i> about that possibility which is perfectly legitimate. I have, myself, asked this question and did not get clear answers for a long time. It may be that it was assumed the answer ‘was obvious’ and therefore unnecessary to be quantified. Well, that is not how science works. If we step up to a programme manager and announce we can reduce the cutting of biomass by 15%, or 30%, we have better have the reliable numbers to back it up.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>For that reason I would appreciate it if you could clarify the % numbers above. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>How many times have we been told that such and such a cooking technology 'saves fuel' or 'reduces emissions' but when examined closely the savings are not there, not obvious, or are only obtained under special, not general circumstances. It would be unfortunate of we did not ask basic questions and agree that the answers are realistic and reproducible before running to market.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I agree with your analysis about why the savings are there:<o:p></o:p></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText>>1. The Peko Pe and most other TLUDs keep the fire focused onto the cooking task.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>>2. These micro-gasifier stoves can use many types of biomass, so any energy-equivalents of cut trees that can be replaced with maize cobs or ag-waste briquettes also means LESS deforestation.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><span style='color:black'>The first point is where the fuel savings are made because nothing is free – if you are saving fuel it can only be by burning the fuel more efficiently or by increasing the heat transfer efficiency, or by being able to control the fire to only give the heat you want at the time (so no heat is wasted with an over-large fire).<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>The second point is where fuel switching makes its mark. If you can burn something that is plentiful and free, like papyrus near Kampala, you have effectively broadened the resource base. If you are burning fertilizer there may be unintended consequences.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>That said, it is not magical or eternal. Pellets are becoming more popular and it is just these sorts of ‘wastes’ that can be made into top quality (relatively expensive) fuel so there is already in some places, competition for the resource. This pressure (competition) will not go away. In other words, always remain sober when analysing the new proposal.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>There are certainly some happy moments ahead where there is such huge waste of biomass like Zambia. <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText>>The Wendelbo project in Zambia with 200,000 rural households is a major effort that should help the world realize that the TLUD micro-gasification is a truly significant part of the solution we all are seeking.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><span style='color:black'>It certainly can be and I congratulate Paal for getting the attention he deserved years ago. When the next wave of innovation comes, it will compete against a different baseline.<o:p></o:p></span></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>>I did NOT say that TLUDs are THE solution. But it is major. This <o:p></o:p></p><p class=MsoPlainText>needs to be recognized and implemented in so many more locations. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Paul, as I have said in other communications, there is more than one way to burn as a gasifier or a pyrolyser and I am always a little surprised that you mention TLUD’s without leaving room for other approaches. I will point to two other ways to burn the same materials in the same gasifying/pyrolysing manner that are not TLUD’s. One is the downdraft stove which has been well discussed here. At this time I feel it is not as efficient for cooking but I don’t want to arbitrarily limit its potential – people are clever, they may invent something. The other is a crossdraft stove which, like the downdraft, has the added advantage of being easily refuelled. Rok’s side-feed achieves this with briquettes. It could easily make char if secondary air ports were added. Both of these alternative layouts can, like the TLUD, make char, or not. I agree completely with <span lang=EN-US>Dean Still on this point: one should be able to choose what mode to use depending on user preference, or the time of year, or any other reason such as seasonal demand for char.</span><o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>>Stovers, the TLUDs are not a bandwagon. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Yeah, well, let’s not beat around the bush. The bandwagons are lining up to jump to the front of whatever wave is arriving. People are very attached to their ideas or technologies or fuels or approaches to burning. It is a stew of possibilities to be eaten with a pinch of salt.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Here is what we have to explain to funders:<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Baseline fuel consumption per day, per week and per year (seasonal variation is significant and one cannot cheat by comparing the high-use baseline moments with low-use improved stove moments).<o:p></o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>The improved stove fuel consumption documented on the same bases.<o:p></o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>An explanation of how the savings are achieved. It has to be scientifically valid. A simple check of the savings should correlate the heat transfer efficiency and the fuel savings, for example. In the case of the current crop of TLUD’s it will be because of improved heat transfer efficiency <i>as fuelled and operated</i> over an open fire <i>as operated in that community</i>. Remember that Tami Bond achieved an thermal efficiency of more than 30% and long before her, Piet Visser did the same thing in Eindhoven. Few improved biomass stoves are much more than 30% efficient so there are open fires and there are open fires. Depends on who is running it.<o:p></o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>4.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>The range of cooking that can be addressed by the proposed stove should be described. Breakfast? Saturday night supper? Weddings? Funerals? Baking? Where is the best fit? That sort of thing. Propose limitations so you are confident in which cooking sector you are going to be able to deliver verifiable results.<o:p></o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>5.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Describe the fuel switching possibilities including what is available and what this means to the user. I will give an example. There is a programme to give Vesto stoves to child-headed households in Swaziland. There are four main selling points: rapid, simple lighting, lower emissions (esp low PM), fuel saving whatever the fuel, and the most important for children: it is usually no longer necessary to walk far to find something to burn. This last point is a fuel-switching argument. Children struggle to gather enough ‘real’ firewood and bring it home. Once they can burn any sort of biomass lying around (unless everyone else is already doing it) there is plenty to collect without having to get wood. The Peko Pe can easily make the same four arguments.<o:p></o:p></p><p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>6.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Opportunity cost. An opportunity cost is what it costs you to give up one thing then do or accept another. In the case of an open fire, it is said the cost is nothing. In Ethiopia they make open fires with artificial clay ‘stones’ that are just the right shape to be able to support the pot, different ones, and to move the stones in and out to create a sheltered fire of different sizes. It has a small cost and is better than a fire on open ground. In short, there are different open fire baselines. Next explain what will your stove cost in money, time, attention and maintenance. Give up <i>this</i>, get <i>that</i>. When the value proposition is greater than the opportunity cost most people will switch/buy the alternative. Stove cost is usually the most important of these, even if the fuel saving is total. In other words, even if a stove cost nothing to run, but it costs too much to acquire, people will not be able to get their hands on one. A big ‘access’ advantage of the Peko Pe is that it is cheap to make. The market for stoves in Zambia has been well studied by social anthropologist Cecil Cook and the prices people are able (not just ‘willing’) to pay have been characterised. This forms part of the opportunity cost analysis. Make your case showing the argument for economic access and impact. If you need a subsidy, give reasons for it and why it is worth it.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>My last point is speaks to the issue of stove subsidies. Lately much has been said here and elsewhere about charcoal (now titled ‘biochar’ but it is still just charcoal, in English) and how it can have agricultural benefit. Ron Larson has presented an argument that it is worth, if necessary, subsidising stoves (increasing access to them) because of the benefits of better agriculture and or a value assigned to the amount of carbon that can be buried in the ground (sequestered). If you introduce an economic argument that has nothing to do with the stove and fuel, you must show separately why that argument(s) is valid on its own. The discussion on this List has focussed on the agricultural benefit and whether they are real. The conclusion in my view is still ambiguous, certainly nothing like as solid as promoting TLUDs as improved stoves. The economic argument based on sequestered carbon is very weak because the value of the trade is unreliable and has been falling. The Chicago-based CCX dropped to 5 cents a ton and then closed. The application of the same money to improving, on a most marginal basis, the management of a power station will have far greater carbon emission savings than even a stove programme, and is much easier to monitor, verify and collect on. This is said without also raising the moral issue of who is benefitting from the (current) carbon trading system.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>On the plus side of morality, the Peko Pe project in Zambia based on what we have read looks like it will be a huge success. That is really good news. Zambia has not been a big stove success story for anyone so far. Let’s hope this time we have a big breath of fresh air!<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Thanks<o:p></o:p></p><p class=MsoPlainText>Crispin<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p></div></body></html>