Akshat Jiwan Sharma

  7 Jul 2026  I thank the Renewable Thermal  Collaborative (RTC) for organising a webinar highlighting some of the recent achievements of thermal energy storage technologies. Conceptually thermal-energy storage is quite simple. You heat up a material and it stores energy either in the form of sensible heat, latent heat (phase change) or thermochemically.  At medium grade, with temperatures  of up to 400C, these systems are hard to beat as they can provide industrially useful heat. This stored heat is highly valuable in food processing and bio refining industries because process temperatures rarely exceed 200C. Besides food processing there are several other industries that can use medium grade heat for drying and preheating.  Since heat is used in all industries, it is the single unifying theme of the entire manufacturing sector and residential too because many electrical appliances are performing temp control work. Thermal energy storage technology is ther...

ABSTRACT Traditional thermodynamic systems are constrained by Carnot efficiency limits, restricting the conversion of low-grade thermal or cold energy into useful work. This study explores a novel approach to overcome these limitations through combined heat (or cold) and power generation, enhancing overall system efficiency. Central to this approach is the proposed AJ cycle engine , a low-temperature-differential, five-process thermodynamic cycle capable of efficiently converting thermal energy into mechanical work with high fuel efficiency. The AJ cycle leverages adiabatic expansion, isochoric and isobaric heat exchange, and controlled heat addition, with fluid circulation aided by pumps and heat exchangers, enabling compact, high-exergy thermomechanical operation. By allowing high fuel efficiency even at modest mechanical efficiency at low temperature differentials and the possibility of miniaturization, the AJ cycle paves the way for versatile applications, including small-scale pow...

I thank the combustion institute for organising a talk on Sustainable Aviation Fuels (SAF) discussing in detail their composition and their climate impact.  Nearly 300 million tonnes of fuel is used by airlines which is a small percentage of nearly 4 Billion tonnes of global annual fuel consumption by the entire transportation sector.  Although the exact figures are hard to obtain, some estimates suggest around 210 Billion tonnes(.14 tonne per barrel x1.5 Trillion barrels) of oil are recoverable as per our current capacity [1]. At the current rate of use all available oil will be exhausted in about 50 years if no new discovery is made.  But new discoveries are continuously made & it is possible more discoveries are made that would add to the list of about 100 or so countries that have proven oil reserves or are already extracting.  It is quite reasonable to assume that easily recoverable oil has already been tapped and further extraction is going to be more diffi...