THE 2014 PROGRAMME
ACTIVITIES
Hands-on Activities with Students
In 2014 the Eco-Center hosted over 50 METU students participating in
Hands-on sessions for the Architecture in situ course, Arch 325 and Arch 326. These students were hosted for
a 6 day program that included visits to local factories and geothermal facilities.
Accommodation was provided in the newly rehabilitated school while meals were prepared and served at the Erdogan Akdag Center.
Once the school kitchen is completed and fully equipped, the building will provide full board and lodging facilities for larger groups.
It is also anticipated that completion of the solar space and installation
of a solar water heating system will allow activities to take
place even when the weather is cooler before and after the summer season.
During Hands-on sessions at the Kerkenes Eco-Center students took part in building and research activities focusing on environmental design and energy efficiency. In the Spring semester a group of 24 students were enrolled in the Arch 325 course.
Some of them worked on the transformation of the existing rocket-stove in the
Sahmuratli School kitchen while others built a new rocket stove in the Kerkenes Strawbale House.
In the Fall semester students registered for Arch 325 and 326 worked on several different projects.
These included innovative usage of AAC blocks as building elements for a Nubian vault and the improvement
of the surroundings of the eco-center using natural materials or ecological techniques.
Rocket-stoves
Several rocket stoves and combustion chambers were
built and studied within the scope of the 2014 BAP grant program.
Rocket Stoves at the Kerkenes Eco-Center
A rocket stove is a special type of mass stove that takes advantage of fast burning wood, especially small diameter twigs and branches,
to achieve a very high combustion temperature. This stove has two main advantages, firstly the ease with which it can be built using
local materials and, secondly, its low wood consumption. On the other hand, this type of stove occupies more space and requires
greater maintenance and care. In the USA rocket stoves are widely employed, and even produced commercially while similar mass
heaters are traditionally found in cold Northern or Continental Europe. The lower consumption of combustible fuel results from the
mass of the stove absorbing heat from the smoke and transmitting it to the room through an air-mass exchange system. Mass stoves are
based on the capacity of the mass (usually a bench or staircase) to give back
the stored heat over a longer time and also at a comfortable level of temperature that avoids over/under heating cycles.
At the Kerkenes Eco-center two rocket stoves were built by students during the Hands-on sessions.
These were built in order to study their performance as well as to promote their use in villages where lower the consumption
of wood or coal is a major concern. Heat transfer principles used in rocket stoves are particularly desirable in Central
Anatolian villages where winters are cold and houses are both insufficiently insulated and lack enough thermal mass to
regulate temperature. The mass of a rocket stove,
if designed in an appropriate way, could also help to regulate and cool
down the temperature of the building during
hot summers by absorbing heat.
Rocket Stoves and Combustion Chambers on the METU Campus
In June 2014, during the Hands-on session on the METU campus, two stoves and three combustion chambers were built.
These are currently being studied to assess and compare their performance.
Preliminary Assessment
A preliminary assessment can now be made. Some of the most important observations are listed below.
• The construction of a rocket stove is simple and affordable. It can be made with local material, the bigger part of the budget being for fire bricks used in the combustion chamber.
It is nevertheless important to follow properly the design specifications of the combustion chamber to avoid bad combustion and smoke.
• During combustion the rocket stove needs to be frequently attended because the fuel chamber is only big enough for one hand-full of brushwood at a time. This is a very small amount of fuel compared to the logs that are used in a conventional stove.
The size of the combustion chamber is determined by the relatively small size of the standard exhaust pipe available in Turkey.
• Villagers remove their stove from the living room during the summer and store it elsewhere. They might thus be reluctant to have an unmovable stove.
This problem can, however, be overcome by designing the rocket stove as a bench, or 'sedir,' that provides a cool sitting area in the summer.
• The time taken to heat-up a room with a "cold" rocket stove is much longer than with a conventional stove because the entire mass of the stove needs to be heated before any heat is released (figs 4 to 6).
On the other hand, once hot, only a small amount of wood is required in order to maintain a comfortable temperature.
• To promote successfully the use of rocket stoves as an energy and fuel saving heating method some other issues, such as its aesthetics, the use of wood rather than coal,
and the need to create a dust free environment, need to be addressed.
Nubian Vault with Autoclaved Aerated Cement Blocks
A Nubian vault is a traditional technique rediscovered by the Egyptian architect Hassan Fathy and used in many of his buildings.
This vault is constructed without the use of formwork. Traditionally such vaults are made with mudbrick or
baked bricks and are usually built to span between three to five meters. As part of the Hands-on project at Kerkenes,
the students were asked to build a small Nubian vault using the Autoclaved Aerated Cement (AAC) blocks.
These light blocks with good insulating properties were thought to
be appropriate because they permitted faster and easier construction as well as having a excellent thermal performance.
A Nubian vault was built at the back of the Erdogan Akdag Center in order to provide a much needed outside toilet facility.
Two groups of students, with the help of an instructor, a mason and two workers, were ale to build the walls and the vault and to render the structure in a few days.
Even if the geometry of this experimental vault is not perfect, it is structuarally very sound and provides a good roof to the small space.
The vault over this new structure is the first of its type at the Eco-center.
It demonstrate that an innovative approach to building has the potential of providing solutions to a wide range of needs.
Mustafa Usta, the mason who took part in the Hands-on activities, expressed his intention of building a similar outdoor toilet in his own house in a neighboring village.
Preliminary Assessment of the Nubian Vault
• AAC blocks are light and easy to shape. The mud mortar used between the blocks provides a good bond at the same time as preventing thermal bridges. However, as each of the blocks needed to be cut the speed of construction was slowed down.
A future development may be the design and factory production of pre-shaped blocks.
This would also allow a better fit and decrease the amount of mortar used.
• Further experiments must be made on the plastering of the vault for waterproofing.
The cement plaster that was applied soon cracked due to its brittleness. Mud mortar is not weather resistant and would need excessive maintenance.
Perhaps a lime based mortar with pieces of glass or other appropriate aggregate would be a satisfactory alternative.
Other Activities within the Kerkenes Eco-Center
Different groups of students worked on small projects that added to the facilities within the Eco-center Compound and the Sahmuratli School Building.
Among these were a geodesic dome, benches and a stele cut out from AAC blocks. These activities are summarized below.
• The construction of a geodesic dome with polycarbonates sheets is an ongoing project on which several groups of METU students have worked since 2013. It encloses an area that can be used either as a green-house or a resting area for sunny but cold days. The geometry of a geodesic dome is based on triangular elements forming a strong and dimensionally stable structure.
The latest operation consisted of replacing the plastic sheet covering the dome by triangles of polycarbonate sheeting.
• The production of a stele replicating the ancient one found on the archeological site on the Kerkenes mountain. Students took exact measurements from the original stone stele now on display at the Yozgat Museum.
AAC blocks were then cut to the precise dimensions. Once assembled the stele was rendered with a smooth mortar.
• Several benches and tables were built using straw-bales, AAC blocks, mud and other local or reused materials in various combinations. An innovative and experimental plaster was used on one of the benches by mixing a clayey mud with colorful pigments and egg whites.
This mixture is known to create a water repellent plaster and its performance is being observed.
Preliminary Assessment
• The geodesic dome
• The production of the stele made from AAC blocks was an exercise that showed students how easy it is to shape the blocks and is a reminder of the close connection between Kerkenes Archaeological Research Project and the Eco-center. The stele was completed within a short period and the result appreciated by the archaeologists. It is to be noted that the conservators who worked in the restoration of the stele uncovered during the excavations had used AAC blocks to restore the stele now on display in Yozgat. It will not be possible to display the original stele of this type where they were discovered (because the burnt and shattered stone is too fragile for exposure to the elements).
This exercise has shown that it would be possible to use AAC blocks to make lightweight replicas of this type in any major restoration project.
Addition of a Solar Space to the School Building of the School Building
The construction of a solar space on the south façade of the Sahmuratli School Building was started in June 2014. The Kerkenes Eco-Center Project team coordinated the activities and the foundation and walls were built. Some students took part in the building activites during the Hands on session.
Working with the local mason taught them some additional building skills.
The solar space on the south façade will provide hot air into the building during sunny winter days thus decreasing the energy needed to heat the building. The thick stone walls of the building provide the thermal mass needed to store the heat during the day and release it during the night when the outside temperature drops significantly.
In summer the openings will be opened to avoid overheating. The space created will be divided into three parts so as to create different conditions for planting,
drying garden produce and providing a comfortable aea for meals and meetings.
Research Conducted by the Kerkenes Team
The Kerkenes team from METU has been conducting research on ecological and appropriate building material and techniques. The main focus of the year has been the research on rocket stoves, their design and performance. Further studies will be carried out in 2015. First results are extremely interesting and show the adaptation of rocket stove to village life. Villagers spend most of their time at home and indoors during the winter and their comfort could be greatly improved with the introduction of rocket stoves at a minimal cost.
The figures below illustrate some of the data collected in 2014.
Art of the research program is the constant monitoring of the Sahmuratli Shool Building in order to to model its behaviour using thermal dynamic modelling software.
Such simulations are important to predict the behaviour of a building and to assess the need for modfication that will imprve its energy efficiency.
Another important contribution to the field of appropriate and natural building materials has been the on-going research on a new clay based material called lightweight loam. Boxes comparing the behaviour of different type of lightweight loam and other natural materials have been monitored throughout the year. The data collecetd furthers the understanding of the hygro-thermal behaviour of the material,
its resistance to rain, its creep and other long term behaviour which are difficult to reproduce inside a laboratory.
It was also possible to use data loggers and sensors on the surface of walls in different buildings to determine the surface temperature of walls built with different materials. South walls and roofs of different buildings were monitored to compare the transfer of energy through the building as well as the delay in the heat transfer.
Sets of data that have been recorded at different period of the year are now available for analysis.
Sustainability and Village Life
The Kerkenes Eco-Center Project has been promoting the use of solar energy and energy efficiency in the village of Sahmuratli since 2006 with funding from the UNDP-GEF Small Grant Program. Solar cookers and solar driers were designed and tested and villagers have been producing jams, stewed fruit and sauces as well as dried garden products that have been much appreciated by those who have visited or joined events. The Kerkens Eco-Center team is thriving to raise the awareness of visitors on such issues such as energy consumption, ecological materials and thermal comfort.
The difficulty remains to find solutions that will make the Kerkenes Eco-Center a sustainable and economically viable institution.
In 2014, production was once more sponsored by a grant from the Ankara International Charity Committee (AICC) and donations from friends and visitors. Amongst the visitors were two Andante Travels groups visiting in May and October.
As in previous years, guests were hosted in the Eco-Center and lunch organised by the villagers.
The Kerkenes products now known by a larger circle of people in the Yozgat region, Ankara and beyond, could be marketed on a larger scale but unfortunately professionals would be necessary to overcome all the bureaucratic hurdles and logistics of trade. Establishing a marketing sector awaits a greater input of finances and professionel services.
The Kerkenes Eco-Center is nevertheless a stage on which different players work on arousing public awareness for the need to occupy our planet in a manner that will enure a sustainable future for generations to come.
Among visitors, the The Eco-Center continues to be closely associated with the archaealogical research program and groups of visitors come on organised tours or by themselves to visit the remains of the ancient city show just as much enthusiasm for the solar cookers and driers.
The ongoing educational programs, Hands on sessions and activities with a potential to become income generating
which involve the Sahmuratli villagers and others in the region need to be developed further.
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