A team of Indonesian engineers has developed a system of keeping transported food fresh and cool that uses the exhaust from motorcycle tailpipes.
Ardiyansyah Yatim, head of the five-man research team, said on Wednesday that the portable refrigeration system was meant to help seafood traders who transported goods from markets to remote villages.
The team wanted to improve small retailers’ system of preserving catches in styrofoam boxes filled with ice and mounted on motorbikes for transportation.
Using this dated method, fish spoil easily during trips to market taking two hours or longer, with the goods losing over 70 percent of their value, Ardiansyah said.
The engineering team’s cooling system, however, could prolong the shelf life of seafood, which reach consumers after a lengthy process of harvesting, packing and delivery.
“We saw that there was potential to generate energy from a motorcycle’s carbon dioxide emissions, which we could develop to generate a cooling system,” Ardiyansyah told the Jakarta Globe.
He was speaking on the sidelines of a science and technology seminar by the Indonesia Toray Science Foundation, which funded the project along with University of Indonesia.
With the grants, the team created a cooling box that essentially mixed the ammonia in exhaust with water to create a heat-absorbing solution.
The exhaust, which contains water and ammonia, fuels a generator which causes the chemical to vaporize and separate from the water molecules. The ammonia is then channeled to a condenser, where the vapor will turn into liquid. This then flows into an evaporator, where the ammonia mixes with water vapor to produce the cooling solution for the portable system.
The project was funded by a Rp 37 million ($4,000) ITSF grant, with Rp 40 million from the university. Most of this went into testing the product in a lab in Central Java’s Kebumen district, Ardiyansyah’s hometown.
“The prototype itself cost less than Rp 1.5 million [to build], but the field survey in Kebumen was really costly,” he said.
The project took eight months to complete, and researchers say they will continue tweaking and improving the system in the coming months.
In laboratory tests, the prototype — which could carry up to 52 liters of liquid or 15 kilograms of seafood — could keep food fresh for up to two and a half hours.
The system, Ardiyansyah said, was able to achieve refrigeration temperatures between minus 13 and minus 4 degrees Celsius from generator temperatures of 100 and 80 degrees.
This means it is feasible to build small portable fridge systems with operating temperatures from zero to 8 degrees — the recommended temperature for storing fresh seafood.
“This system is suitable for transporting seafood products in a rural-coastal area with a contoured terrain, where the locals rely on motorcycles as their main mode of transportation,” Ardiyansyah said.
“There are no moving components in this system so it’s easy to maintain,” he added.
Though a cooling system without a compressor is not new, the invention does not need to use an electrically generated heat source like other noncompressor systems.
“The innovative part of this system is that we use the heat contained in the exhaust gases as our source of power,” said Ardiyansyah, also a mechanical engineering lecturer at UI.
This self-powering feature comes from ammonia’s ability to turn into vapor after absorbing heat and mix with water.
The cooling solution, which absorbed all the heat from the food, flows back into the generator, powering the machine, allowing the cycle to repeat.
After the lab tests, Ardiyansyah said, the prototype would have to be modified by the engineers to reduce its weight and improve its efficiency.
However, the device has already shown that it can be used as an environmentally friendly and energy-saving system for transporting seafood in rural and coastal areas.
The next phase of the project, Ardiyansyah said, would be to experiment with an actual motorcycle-mounted unit and to publish their findings in a peer-reviewed scientific journal.
The head researcher said if the product was successful, the team might register for a patent.