Evaluation of Technical, Environmental and Financial Viability of Tri – Generation in Apparel Sector of Sri Lanka
Apparel industry is the main source of foreign currency for Sri Lanka and is the one that provides most number of local employments. It has been severely affected by the continuous rise of fossil fuel prices. Industry is also under pressure by the governments and buyers (major retail chains and global apparel brands who has their supply chain emission reduction goals) to minimize the emissions as well as to reduce the energy consumption. In view of that, this study was focused on the viability of using combined
heating, cooling and power generation or the Tri‐Generation (TG) at factory level which has never been tried in the apparel industry in Sri Lanka.
After the literature survey, local apparel sector was analyzed and then the factories were categorized in to five main groups out of which the most affected group by the energy cost, the fabric manufacturing, was selected as the focus group. One factory from the focus group, Textures Jersey (TJ) was selected for the initial case study. After a detail
energy audit at TJ, results were used to evaluate the environmental and economical viability of two selected TG combinations. One with most favorable results was
optimized and then studied in detail to see if it is environmentally, economically and technically viable to TJ. Result of the detail analysis of the optimal TG combination was used to come up with general guidelines to implement viable TG plants for local apparel industry.
As per the results TJ can enjoy substantial benefits (15‐35% energy cost saving) by opting to use a TG, fired by either coal or biomass (saw dust briquettes or firewood). Biomass is preferred over coal due to low prices and reduced emissions. Not needing of a complicated fuel preparation and feeding system as in a coal fired TG system is also an
advantage of Bio‐mass. However biomass has relatively more supply chain issues compared to coal. A universal solution that can be used by any apparel factory cannot be
arrived at, as economics of the TG is highly depended on local parameters. However selecting the capacity of a TG based on the process heating demand of a factory is
beneficial if it has a 24 hour operation. Intermittent operation of TG is not economical as frequent start‐up and shut‐down of a TG is not practical. Further, increasing electricity
generation in TG is not very attractive owing to subsidized tariffs.