During my trip to the Mangrove Services Network (MSN) in the Delta region of Bogale, I had the great fortune to visit a small stove factory that they had helped establish. The mangrove forest, which used to grow extensively on the shores of the Ayerwaddy River Delta has been decimated in recent years by people establishing shrimp farms and cutting the trees for conversion into charcoal. I was shocked to learn that shrimp farms only have a limited productive life and are often abandoned after only 5 or 6 years. Of course, once removed, the mangroves take decades to re-establish themselves by natural regeneration, if they ever do. The loss of the mangrove forest was a significant contributing factor intensifying the extensive destruction and loss of life caused by Cyclone Nargis in 2008. To counteract this, the work of the Mangrove Services Network has two main thrusts. The first is to identify the strongest mangrove species that will re-establish quickly and permanently and help the local people to plant these trees in their community. The second thrust is to help local inhabitants develop alternative sources of livelihood, so they are not forced to cut the mangroves for income.
One of these MSN livelihood projects was a stove building factory using a kiln that burns rice husks as fuel. Rice husks are a low value by-product of rice growing in the Delta and are freely available everywhere. Without a good draft of air, they tend to smolder and produce a great deal of smoke. However, MSN overcame this drawback by using a 30ft high chimney which creates a huge draft that helps the husks burn cleaner. They have a damper in the system that allows them to control the burn and thus, the temperature of the firing. A wonderful by-product of this process is the ash that is left when the burning is complete. Rice husk ash is high in silica content and when added to the clay mix, it gives the stoves added insulation and resistance to heat. For me, this a win-win situation: a waste product from agriculture is being used productively, then the by product from its combustion is helping the stoves perform better and last longer.
But there is still room for improvement. In the future, I hope to work with MSN to improve the design of their stoves. At the moment, they are using a knock-off version of the Thai bucket design. While cheap to produce, it is not a very efficient or clean burning design. On my next visit to Bogale I hope to help the stove builders learn about the principles of the Rocket Stove and develop with them a design that will fit their production facilities and be popular in the local market. Please help Solar Roots and the people of the Ayerwaddy Delta to preserve the mangrove forest and to improve the lives of the local inhabitants. Your support is greatly appreciated.
In June 2014 Solar Roots went down to the Bogalay region of Lower Burma to install a solar system for the Mangrove Services Network. I was accompanied by two students from UC Berkeley, who had come to work with Solar Roots as volunteers. Arriving at Bogalay township, we made last minute puchases of materials before setting off by boat to Mangrove Island, which is located 45 minutes south of town, in the middle of the Bogalay River.
The island is about 30 acres in extent, but only 2 acres are actually solid ground above water level, and those were created by bringing in sand and tamping it into place! The rest of the island is made up of mangrove forest, some of it planted by Mangrove Service Network (MSN) to select the best species for re-establishing the native trees. Mangroves have been devastated in recent years, by people establishing shrimp farms and converting the trees into charcoal for the urban market. MSN labors mightily to replant the mangroves and help local people develop alternative sources of livelihood. Here is their website:http://mangroveservicenetwork.org/.
MSN uses the island as a research center and training facility, holding about a dozen trainings per year. Before we arrived, power was provided by a large diesel generator, which was extremely expensive to operate, due to the remoteness of the site. I proposed to MSN that we install a hybrid solar/ generator system, so that they would always have sufficient power, particularly when there was a long training or in the middle of rainy season. During our time on the island, rainy season was just beginning, and daily downpours with thunder and lightining were the norm. At the end of the work day, we three Solar Roots folks would bathe in the river, often in lashing rain and keeping an eye out for roving crocodiles!
With the two permanent staff who live on the island and maintain the facility, plus several other MSN staff, we installed 4 x 80W solar panels, a 150Ahr battery and a 1,500W inverter. The installation included one of my favorite solar devices, which is a manual tracker that allows the user to turn the panels by hand, following the sun during the day. This can add another 20-30% of solar production which is especially useful during rainy season. The solar system will provide enough power for lights, water pump and the occasional video during the seven months of dry season, but should be supplemented by the generator during the rainy season.
After four days of cooperative work between the locals and the Solar Roots team, we had installed a robust system that should provide power in all seasons. I'm sure I will return to work with MSN - they have an interesting rice husk-burning kiln that is used to fire their ceramic stoves at another livelihood project. However, I'll try to schedule it outside of rainy season!
The Institutional Stove
There are many institutions in Burma that cook food in large quantities, such as schools, orphanages and monasteries. In Naung Taung monastery, (see last report), it is normal for 1,000 people to sit down for lunch! I had conducted a successful stove training there earlier and I was determined to build a scientifically designed Rocket stove to replace the existing inefficient and smoky fires.
After several disappointing trials with insulated clay bricks, I determined to use a more durable material for the combustion chamber of our institutional-sized stove. I chose stainless steel, as it resists the effects of heat much longer than mild steel. Although stainless steel is imported from China and it is relatively expensive in the Burmese context, I wanted to see how it would perform.
With some other stoves I had built in the past, cooks complained that there was not enough heat, so this time I decided to use a combustion chamber that was 8” by 8” square – a real giant! I was ably assisted in the building phase by Hamish Lee, our New Zealand volunteer, who had a engineering background and good construction skills.
Stainless steel is a very hard metal, difficult to drill through, but with the new spot welder I had recently brought from the US, making the required joints was no problem. For stability and to hold the insulation around the combustion chamber, I placed it inside a 55 gallon drum. This is similar to the design used by Instove, a non-profit stove builder based in Oregon.
Inside the drum and surrounding the combustion chamber I placed wood ash collected from previous fires, which insulates the chamber and slows down the heat loss to the outside.
After 2 days hard work, Hamish and I had the stove ready for testing. With a ten foot high chimney, also 8” x 8”, creating a mighty draft, the stove burned extremely hot and produced almost no smoke after start up. Everyone was impressed!
Later, with two other volunteers from the US, the stove was installed in the kitchen of St Mathews Orphanage Center, where it is being used on a daily basis. I am very curious to see how the stainless steel holds up to the intense heat and what the cooks have to say about the convenience and performance of their new institutional stove.