For Mongabay India
Published on 22 March 2024
Pottery is an energy-intensive industry, with traditional kilns taking 36 hours to bake the clay ware. Access to firewood to fire the kiln is also increasingly challenging.
In the Kachchh region, an improved kiln has reduced fuel requirement to 40-50%, as well as reduced time to four to five hours.
The improved kilns are helping conserve time and effort of the potters, as well as reduce production costs. Moreover, with reduced fuel usage, carbon emissions have also reduced.
Potter Ramjubh bhai (sitting, on left) interacts with another potter in Kachchh as they make the improvised kiln for him. Image: Khamir
An initiative introducing energy-efficient kilns to traditional potters in Kachchh, Gujarat, reduces firing time and firewood requirement, addressing concerns of energy-intensive pottery-making while benefiting both artisans and the environment.
Pottery is an ancient craft and in parts of Kachchh, Gujarat, its history can be traced back hundreds of years to the Indus Valley Civilisation. There are about 55 villages in Kachchh where the potter community resides and works. Making objects out of clay is a long process, with multiple steps from sourcing the raw material to moulding the prepared mixture on the potters’ wheel to finally firing the kiln to bake these pots. Over time, each step has become fraught with challenges — access to firewood, for instance, to fire the kiln, is now more difficult as plantations are being removed for infrastructure development.
In 2023, an initiative to introduce energy-efficient kilns to potters in the region has brought new hope. Not only is it saving time — from 36 hours in traditional kilns to four to five hours in the energy-efficient one — but it also reduces the firewood requirement by up to 50%, thereby benefiting both the potters and the environment.
The improvised kiln reduces firewood requirement by up to 50 percent, thereby benefitting both potters as well as the environment.
Image: Khamir
The improved kiln, designed by IIT-Delhi’s RuTag (Rural Technology Action Group), in association with Khamir, a local NGO working with craftspeople, was first set up in Ramjubh bhai’s house in Bhuj. He says, the kiln has reduced fuelwood requirement and time taken for the process. “It also took one-third of the time – just four to five hours – to bake the clay,” he said.
Traditional, but energy-intensive
Traditional pottery-making methods in the Kachchh region of Gujarat have stood the test of time, passed down through generations like cherished heirlooms.
Pottery is an energy-intensive industry. In pottery production, the kilns used in small-scale industries are highly inefficient, consuming larger fuel quantities compared to the actual energy requirement for the process. Most rural potters depend on traditional kilns burning firewood with poor energy utilisation where majority of energy go wasted. When firing the kiln, 70% energy is lost on the walls and the floor of the structure.” found an energy audit of pottery kilns in Maharashtra and Chhattisgarh conducted by IIT-Delhi professor M.R. Ravi and others. Like Kachchh, the audited kilns were also updraught, meaning the pottery is placed on a platform and fuel is burned underneath. The fire rises through the pottery and exits from the top.
Ramjubh bhai, who draws his lineage to a long line of potters, said that the traditional, open-fired kiln takes about 36 hours to bake the clay products. “After the earthquake in Kachchh in 2001, we were introduced to a kiln designed by the late Gurcharan Singh, which reduced the baking time to 15 hours,” he said. Studio potter Sardar Gurcharan Singh is known to have pioneered traditional pottery into an art form and was awarded the Padma Shri, India’s fourth-highest civilian award, for his contribution to the field of ceramics.
Though Singh’s innovation took less time than the traditional kiln, the time taken still accounted for more than half a day. “Moreover, these kilns are batch kilns, meaning the clay products are taken out once the kiln has completely cooled down. So, there is no recovery of energy,” Ravi of IIT-Delhi told Mongabay India, “So our aim was to improvise the kilns such that energy could be saved. This could be done by minimising the material that is heated during the firing. We had to think of how to lighten the walls and the structure in order to reduce energy loss.”
The improvised kiln next to which potter Ramjubh bhai stands was designed by the IIT Delhi RuTag team in Kachchh. Image: Azera Parveen Rahman
An air gap to save energy
The idea to make energy efficient kilns in Kachchh, said Ravi, was along the same lines as their work with the potters of Chhattisgarh and Maharashtra. They had to create insulation to reduce energy loss, but instead of asking the potters to get expensive insulation material, they decided to use the rat-trap bonding method.
“The rat-trap bonding method means that there is a gap between the innermost brick wall and the outermost wall. This air gap will create an insulation layer that is free of cost,” Ravi explained, “One of our Ph.D. students, Sunil Gokhale, suggested this, saying that in Western countries, many building structures are built this way.” The air gap in the kiln was three inches and so was the wall thickness on either side. Similarly, a gap was introduced between the lower brick floor of the kiln, where the wood is burnt and the ground on which it rests. These air gap insulation layers would minimise energy loss.
The improved kiln has helped potters in many ways. In addition to the advantages mentioned by Ramjubh bhai, such as reduced fuelwood consumption and time savings, there are further benefits. Ismaeel bhai, another skilled potter, noted a significant decrease in pot breakages. He emphasised that the pots are now baked uniformly, ensuring higher-quality output.
However, there was a challenge — cracks started appearing on the wall of the kiln after the firing. Ramjubh bhai, who was involved in the making of the kiln, discussed the issue with Khamir and proposed that the alignment of the bricks be changed, “instead of keeping it standing on its narrow surface, lay the brick on its wider surface” to increase the strength. This reduced the air gap to two inches. “One of my students who was in Kachchh at that time called to ask me about this. The design will work as long as there is a one or two-inch air gap, so I gave the go-ahead,” Ravi said. Hence, for the rest of the 19 kilns that have been built in different villages in Kachchh till now, this tweaked design has been implemented.
“The rat-trap wall’s reduced thickness saves a lot of energy, but its structural strength is low because of which cracks can appear after firing. So we have asked potters to plaster the walls with clay if this happens,” Ravi said, “Meanwhile, we are working on sealing the wall with a steel belt to improve its strength.” The team is also in the process of experimenting with industrial-quality bricks that can tolerate higher temperatures.
In the meantime, Khamir is planning to build more than 20 such kilns in potters’ villages. “Our plan is to continue involving the potters in the construction so that they can learn the technique and replicate the design,” said Ghatit Laheru, the director of Khamir. Khamir will bear the production cost of such kilns, amounting to about Rs 30,000, while the potters contribute by making the kiln itself.
Saving energy means saving costs, time, and effort
One of the immediate impacts of saving energy is that the amount of firewood required to fire the kiln is less. “This would be of great help to us because unlike earlier when stems and branches of Gando baval (Prosopis juliflora) would be easily available, now access is becoming difficult,” said Sajid bhai, 24, a potter in Naliya, about 100 kilometres from Bhuj. In Kachchh, Prosopis juliflora, an invasive species is commonly spotted. However, according to Khamir, the charcoal industry, which clears large swathes of these groves for its use, is one of the reasons why access has become difficult. “We, our families, have to walk three or more kilometres to get these branches now,” Sajid bhai said.
Potter Sajid bhai stands next to the improvised kiln built at his home in Naliya, Kachchh.
Other than the struggle to access firewood, experts highlight another big concern. Ravi from IIT Delhi said that in Gujarat, waste material is often used to fire kilns because of the industries around. In urban areas, especially, Dipesh bhai of Khamir added that waste cloth and plastic are used to fire the kiln. “As you can imagine, the fumes that emanate from burning these materials are very harmful to health and the environment,” he said.
Potters using the improved kiln, they will be able to fire it more often and make more ware. Sajid bhai says that pottery work is mainly done only for four months in the year, which are the summer months. This is when the kiln is fired. This work stops in monsoons. For the rest of the year, they make enough stock of the finished product. He also said that with the improved kiln, he hopes to be able to fire his kiln more often and make more ware. “As of now, I fire my kiln two or three times a month. We make the clay pots in bulk and fire it together,” he said. He mostly sells his ware at fairs and in the local market.
Over the next few months, Ravi and his team also plan to conduct an energy audit of the improved kilns. “The potters are noticing a 40-50% reduction in fuel requirement, so there is 40-50% less carbon emission,” he said. These kilns are therefore not just helping the potters, they are benefitting the environment too.
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