Integrated sustainable energy solutions for large- and small-scale communities

Abstract

Devising sustainable energy for large- and small-scale communities requires two different perspectives. While, in the former, the main challenge is the allocation of relatively abundant resources to meet the supply for generic demands, in the latter, the detailed properties of the resources and demands should be identified and matched. First, this thesis focuses on one of the challenges of energy development simulations for large-scale communities. A novel CSP performance model is proposed for whole-of-grid simulations, that despite the usual simplified models in the literature does not compromise the major performance parameters. The model is first used to estimate the performance of a new CSP project and then its results are compared to those from a simplified CSP model in a whole-of-grid simulation. The comparison shows a significant overestimation in the case of the simplified model. The second part of the thesis focuses on two sustainable solutions for small-scale communities. In the first proposed solution for Nauru, the recovered waste heat from the diesel generator-based power plant of the island is utilised to supply cooling power required for the preservation of imported food in the island and increase the production of permeate water of the island’s desalination units by heating its inlet water. The solution supplies the whole required cooling power, reduces the carbon emission of the island by 1.1 kilotonnes and increases the annual freshwater production by 81 million litres. In the second proposed solution, several combined cooling and power (CCP) units, fuelled by agriculture residue and household waste supply electricity and cooling power for different districts of Tonga. The results show that the optimum combination of the CCP units supplies 38% of the total electricity demand of Tonga and provides 3700 m2 of cold storage area, sufficient for preserving the prospective yield of the exploitation of 27% of the total fallow land.