Mayon Turbo Stove: Evolution

MENU
MTS Evolution
MTS Design Package
Phillippine Case Study
Gambia Case Study
Carbon Credits
Online library

To develop the MTS, all major conical rice hull stove designs available in the Philippines were analyzed including versions from the International Rice Research Institute (IRRI), PhilRice, the Central Philippine University (CPU) and compared to the Lo-Trau model developed in Vietnam. All stoves were functional but suffered from one or more deficiencies including incomplete combustion, excessive air, uncontrollable fuelbed fires, high rice hull consumption, constant need for tending and high production costs.

Through an intensive research and development program, REAP-Canada created an advanced combustion appliance from the basic Lo-Trau conical rice hull stove design by making the following design changes:

The inner cone was lengthened by approximately one third to increase residence time of gases and concentrate the flame under the pot
To prevent smoke events (as the porous rice hull turns to ash it restricts the air supply), twin air injector pipes were installed through the ash pan to draw air into the combustion zone above the burning fuelbed. The twin pipes increased the turbulence inside the inner cone, creating a vortex and slowing airflow out of the stove.
Secondary combustion air holes were also drilled into the inner cone to add additional air to more completely combust the gases as they circulated in the top of the cone. The innovations of extending the inner cone and the strategic reengineering of the air supply to create an adequate (but not excess) air supply with effective air mixing provided the breakthrough in clean combustion.
To minimize fuelbed fires and eliminate smoldering of rice hull in the hopper, a heat shield was added around the centerpiece. This was formerly a major problem with all rice hull stove designs when the centerpiece would heat up and ignite the hull supply.

MTS manufacturers in the Philippines delivering stoves to the communities.

After a 3-5 minute start-up period, a blue or non-luminous flame was present throughout the inner cone of the MTS. Maintenance of the stove is also reduced, with tapping required only after approximately 7-10 minutes from start-up to introduce additional fuel. The stove is now thought to possess a near optimal air flow; there appears to be no excess air and no oxygen deficient areas of the cone or oxygen deficient periods during the entire burn cycle. Following start-up, smoke only begins to appear again when additional fuel is required to maintain combustion. There are no smoke events related to lack of air when adequate fuel is present. The burnt ash is now a whitish-grey colour, indicating more complete biofuel combustion.

A smaller model of stove the MTS 6500 (having a 6.5 inch diameter fuelbed) has also been developed. The original MTS-7000 model (having a 7-inch diameter fuelbed) appears best suited to larger households (10 or more members) or small commercial applications. There has been favorable feedback from Philippine communities using the new MTS models with some reporting 100% substitution of conventional fuels. The new MTS 6500 stove can allow a family of 6 to cook with approximately 1500 kg of rice hull per year. With a simple level of training, families are now enjoying a high quality non-luminescent flame cooker that is becoming locally known as the poor man 's gas stove.

Learn more about:

Additional information on the MTS can be found in the on-line library.