Searching for an insertable insert stove
Ronald Hongsermeier, July 24, 2008

Tom Reed,

Vesto +_ Switchgrass Pellets Crispin Pemberton-Pigott, New Dawn Engineering, Roger Samson, REAP Canada, January 5,2008 Densified Canadian switchgrass pellets were burned in a VESTO (New Dawn Engineering) stove in the gasification mode. Dear Grass Burners Roger Samson was here today with Stephanie and he brought along a Mayon Turbo stove with rice husks and a big bag of switchgrass pellets. We tried this 'fuel of the future' in the Vesto which first required putting a small sheet of newspaper at the bottom to keep the little pellets in, and second perforating the sheet to let in a least a small amount of primary air. It was packed pretty tightly. The pellets are about 15 MJ per litre. We lit it on top with a small wood fire and it got going nicely. It burned very much like a Vesto with the 'gasifier mode' engaged meaning that it ran with very little primary air getting through and a floating bed of flame perhaps 7 cm above the fuel. Very pretty. The CO/CO2 ratio was stable at 2% and had no odour or visible smoke. I will get some picture posted and a movie with a description by Roger. The flamefront was shallow, as Alex describes with wood pellets. Nothing really to add - it burned completely and gave off lots of heat. Regards Crispin

Dry Fuel Equivalent Calculator
Crispin and Nigel Pemberton-Pigott, October 2007

Dear Stoves Testers

See the attached Dry Fuel Equivalent Calculator drawn up for evaluation by our list readers.

There are 4 pages to the spreadsheet. The first is where a test result can be entered. If you only know the mass of damp fuel burned, the amount of charcoal remaining and the moisture content of the fuel, it should be sufficient.

Select a suitable dry fuel heat content from the chart on the right if you don’t know the figure exactly.

The first set of numbers is the actual heat value of the fuel that was offered to the pot. The second sheet is the heat value as calculated by the UCB-WBT method. The Dry Wood Equivalent figure in the UCB-WBT is not used (as previously discussed), but a different formula which can be seen in their spreadsheet by clicking on the cell.

The difference between the two output figures is calculated on the third page.

The fourth page is the two methods plotted in two different manners, the actual value of dry fuel equivalent against the UCB-WTB for a range of moisture and charcoal remaining, both as a % of wet fuel burned, then the relative value of the outputs.

You will notice, playing with the numbers, that when the heat value of the fuel is more than about 20 MJ/Kg the dry fuel equivalent has been under-reported by the UCB-WBT. Conversely, when the actual heat in the fuel is less than 20, that method over-reports the heat yielded giving the impression that the stove has not performed as well as it actually did. In the case of a fuel like rice hulls, the difference is significant. Note that the charcoal heat content should be changed for the rice hulls – see the small chart on the right of page 1.

As always, please look for errors in the calculations. Sorry about the formatting of the graphs – the cells with no or very high plus or minus values get plotted as zero, mostly in order to make the lower moisture calculations more readable.

Best regards
Crispin and Nigel Pemberton-Pigott
Waterloo
Ontario

Heat Content of Ethanol Gel
Crispin Pemberton-Pigott, August 26, 2007
Dear Friends

Maputo Ceramic Stove Update
Crispin Pemberton Pigott, New Dawni Engineering, Swaziland, June 6, 2007
MCSi

Jigger Mould Making for the Maputo Ceramic Stove
Crispin Pemberton Pigott, New Dawni Engineering, March 7 2007
Finished, cured moulds
This is a set of pictures to show the process for making the moulds. The results are quite impressive - smooth and hard, beautifully formed. We can make about 10 or more moulds per day using the Jigger mould holder as a form.

Charcoal and Communities Conference Planned for 2007
Global Non-Timber Forest Products Partnership (NTFPi) September 14, 2006

STOwsi Cookeri - Low Cost Concrete and Ceramic Stove
by Crispin Pemberton-Pigott (PROBEC)
25 Sept 2006

Designii Brief:
The development of a stove for use in low income areas of rural Senegal.

Maputo Ceramic Stove Images August 23, 2006
Crispin Pemberton-Pigott, New Dawni Engineering, August 23, 2006

Crispin has provided us with the following images of his new MCSi 200 stove.

MCSi 200 Profile View

Glazed Maputo Ceramic Stove
Crispin Pemberton-Pigott, New Dawni Engineering, August 23, 2006