In this chapter a thorough review of the latest research findings on power generation from non-conventional low heat sources is presented. Main discoveries and results of research works ranging from source exploitation technologies to final power production are reported and discussed to offer an overview of their potential. Firstly the concept of low-grade source is presented and the main energy sources in this group (i.e. geothermal energy, solar thermal systems, industrial waste heat and ocean thermal energy) are introduced. Each of them is briefly described and the latest developments and improvements on the technologies for their exploitation are enumerated. Afterwards the state-of-the-art available power cycles for the conversion of low heat into electricity are reported. Only thermal power conversion technologies are presented due to their higher presence in commercial applications and their potential for small scale power generation. Among these technologies, last findings and results on organic Rankine cycles (ORC) and power cycles based on working fluid mixtures (e.g. Kalina cycle) are described. A special emphasis is placed on organic Rankine cycles (ORC) since over the last few years this technology has experienced a significant global growth, boosted by their viable performance and the inherited knowledge from the refrigeration industry. In addition, the suitability of less known technologies such as Stirling cycles and their current development status and perspectives are also commented. After this review it follows an examination of the implementation of these technologies in present power production systems. Discussion will be provided on which are the current barriers that the mentioned technologies are facing for their introduction or during their operation. On the other hand, practical restrictions concerning the availability of suitable technology, environmental requirements or economic viability are stated. Limitations regarding thermodynamic and technological aspects, as well as operational concerns will be considered of special interest. In the final section we deal with the future scenario for the integration of small-scale power generation. Potential solutions for overcoming technology development barriers are presented and directions of current research works on this topic are pointed out.
|Title of host publication||Advances in Energy Research and Development|
|Publication status||Published - 2014|
Subject classification (UKÄ)
- Energy Engineering
- power generation
- renewable resources
- low heat sources