Wednesday, October 23, 2013


Katsumwa farming club still going strong with irrigation, even as rainy season approaches.

Monday, October 21, 2013

Chibanzi: early land preparation and beehives

Chibanzi farmers started beekeeping last week with two beehives. They also showed us their gardens, ready well in advance for the rains to come.

A good yield

Onions at Mziza and tomatoes at Katsumwa. Farmers use late season harvests to fund bigger gardens during the rainy season. The onions pictured below are worth about $100, or enough capital to plant 1 acre of corn. The basket of tomatoes sells for $10 to $20, depending on the market.

Saturday, October 12, 2013


Bees take residence in a beehive. Honey is sold to raise money toward the next growing season.

Friday, October 11, 2013

Mr Store does it again

While most farmers are busy preparing their upland garden to plant maize in the rainy season. Mr. Store is already planting maize, which will be irrigated for next two months until rain arrives. 
He is also harvesting and selling onions. Mr. Store is an outstanding farmer, harvesting and planting throughout the year.

Wednesday, October 9, 2013

Farmers are ready for the rain at Mziza

Early preparation for rainy season planting is now complete at Mziza. Farmers have been trained to prepare early by making ridges and weeding their gardens. They also gather the fertilizer and seeds as soon as possible in the year.


Sunday, October 6, 2013

Iterations of the piston pump

Below are three iterations of piston pumps, which we have built and used on our windmill. 

The first is a 1-1/2" PVC cylinder with a 1" PVC piston. On the bottom of the cylinder there is a 1-way valve (that only let's water into the cylinder). On the bottom of the piston, inside the cylinder, there is another 1-way valve that only allows water to enter the piston pipe. As the piston moves up and down, it alternately creates low and high pressure in the cylinder. Under low pressure, water is sucked into the cylinder through the bottom valve. Under high pressure, water is forced up, into the piston pipe. The piston pipe is connected to the water tank (via a flexible hose that accommodates the up and down movement). Performance: low output due to significant leakages between the piston valve and cylinder wall: 400 l/hr in light-moderate winds.

Next we upgraded to a treadle pump. The treadle pump is modified so that the piston can be attached to the pumping rod. Also, we do away the suction pipe typical of treadle pumps by submerging the pump in the water. We run only one cylinder, while the other cylinder is blocked so not to leak pressure during operation. This pump put out more than 10,000 liters per hour, but required strong winds to get started. Ultimately, it put too much stress on the windmill components, and would need a larger windmill to be a viable pump option.

Currently we are running the pump pictures below. This pump has some advantages. It has 4 cylinders, and can be configured to run on any combination of 3, 2, or 1 cylinder. We tested it on 4 cylinders and 2 cylinders. Due to light winds on the day of testing, 2 cylinders showed better results. It pumps in the range of 5,000-7,000 liters per hour in moderate winds.

One advantage of this pump is that the cylinders are 1-1/4" PVC and the piston seals are leather bicycle pump seals. This makes for a rather affordable pump. Each piston is made of a bolt, a nut, two metal washers, and two leather seals, the total cost for which is not more than $0.75.