The Challenge / Concern:
Low grade heat (water at 70-90oC) is wasted at energy intensive plants. Electrification of such low grade heat is not feasible by conventional routes such as stirling engine, thermoelectric, thermoacoustic etc. A more efficient device was desired which would have lesser dead work and wider compliance for variation in source and sink temperatures.
Brief (and non-confidential) Solution
A piston free engine has been developed at KalpaSrusti. Being piston free, it has much lesser frictional losses. Due to motion of solid workpiece through liquid, it has lesser deadwork needed to be done in order to harvest the power. The engine works on buoyancy variations due to temperature of the workpiece. Though the work done by the unit engine is small, array of the numerous units attached to single output shaft produce significant output. Space requirement by the unit structure is much small. The array can harvest some work while transferring heat from the low grade sources to the atmosphere. Harvested work can be used to run dynamo for electrification.
Service / Project: Contract Research