The guest house offered a fine breakfast spread for all of the guests
around one large table filled with boiled eggs, bread, jam, local
honey, and passionfruit juice. After doing some brief shopping for
souvenirs at the guest house shop, we departed Kasiisi and drove our
rough dirt road in reverse. We only had to stop once to let a baboon
cross the road. Viennay, Ankh, and Lauren followed us in a separate
We immediately jumped into giving Viennay a tour of the SND grounds so
he could formulate his ideas of whether the site merited a biogas
digester at all, and if so, where the best location would be. This
took some time, but finally we all sat down in the coolness of the
convent and discussed the project with Sister Rita. Viennay confirmed
EWB's views that a digester would work well here, and the farm had
ample animal wastes to use, along with the potential for using latrine
waste, kitchen waste, and crop waste. While Viennay has built almost
30 fixed dome digesters and is an expert in their construction, EWB
proposed working with him to develop a plug-flow design for the site
that would be more efficient in terms of gas production. This design
would hinge on gathering information on an acceptable method of
sealing a flexible membrane top to the concrete digester, and EWB
offered to test some prototypes over the next 6 months in Cincinnati.
It was a positive conversation that could lead to an innovation for
Green Heat. Vianney also shared with us his interest in developing a
method of heating very large cookpots with steam from a biogas heating
source, so that he could surpass the sizing limits of available
Ugandan burners. We offered to bring this challenge back to our stove
committee and see if they could assist.
Later in the evening, Vianney shared his spreadsheet calculator that
he uses to determine potential gas production from various wastes and
for digester sizing. This could be a valuable aid as we work together
in the future and can compare numbers based on similar assumptions. So
far, we have been working with a variety of assumptions and data from
differing sources, and our results have been all over the place.
Another positive outcome for this trip!