HighlightsOn dry basis, typical human faeces contain 83 wt.% organic fraction and 17 wt.% ash.The LHV of dry human faeces ranged from 19 to 22 MJ/kg, values similar to wood biomass.Syngas from dry human faeces had LHV of 15–17 MJ/kg at equivalence ratio of ∼0.31.Energy is best recovered from moist human faeces at equivalence ratio above 0.6.Recoverable exergy potential from moist human faeces can be up to 15 MJ/kg.

HighlightsDry human faeces have a Higher Heating Value (HHV) of 24 MJ/kg.Faeces combustion was investigated using a bench-scale downdraft combustor test rig.Combustion temperature of 431–558 °C was achieved at air flow rate of 10–18 L/min.Fuel burn rate of 1.5–2.3 g/min was achieved at air flow rate of 10–18 L/min.Combustion temperature of up to 600 ± 10 °C can handle 60 wt.% moisture in faeces.

HighlightsEnergy and water recovery system from human excreta is modelled in Aspen Plus.The Nano Membrane Toilet is proven to be a self-sustained system.Up to 87% of total amount of water fed to the system can be recovered.Net power output of the entire system is similar to the USB port peak power (2–6 W).The specific net power output varies between 23.1 and 69.2 Wh/kgsettledsolids.

There is a large imbalance between demand and supply of energy in Nigeria, with inefficient power supply being the country’s greatest economic bane. Aside energy crisis, fuel is a luxurious commodity and petroleum diesel is the predominant fuel for power generation, particularly in the industrial sector. As a result, the country suffers from forced power outages, and persistent black out while residents and industries are forced to depend on self-generated electricity. These have notably reduced industrialization and increased environmental pollution across the country. This paper proposes the use of Jatropha biodiesel as a substitute fuel to petroleum diesel. It examines the energy efficiency and environmental life cycle impact of the production and use of 1MJ of Jatropha biodiesel in a typical 126 MW (ISO rating) industrial gas turbine power plant with multi-fuel capability using life cycle assessment methodologies and principles. A net energy ratio of 2.37, 1.54, and 1.32 and fossil fuel savings of 58%, 36% and 27% were achievable under three farming system scenarios: a) base-case rain-fed, b) base-case irrigated and c) large scale farming system. Also, an environmental benefit with GHG savings of 19% was attainable under the three farming scenarios. The results demonstrate that the contribution of GHGs and effect on climate change is most significant with the end use of the fuel. It also highlights the importance of clear definition of the reference system which should be indicative of the local production system and comparative to the system under study. A favourable business and economic climate driven by demand is proposed for Independent Power Producer (IPP) to generate power for off-grid users instead of generating power for the national grid using a decentralized Jatropha biodiesel production system coupled to waste to energy technologies. This could significantly improve the energy situation; diversify the energy generation mix and fuel supply in Nigeria, especially for small-scale businesses and the rural population.

The recent advances for flexible fuel operation and the integration of biofuels and blends in gas turbines raise concern on engine health and quality. One of such potential threats involves the contamination and the growth of microorganisms in fuels and fuel systems with consequential effect on engine performance and health. In the past, the effects of microbial growth in fuels have been qualitatively described; however their effects in gas turbines have not necessarily been quantified. In this paper, the effects of fuel deterioration are examined on a simulated aero-derivative gas turbine. A diesel-type fuel comprising of thirteen (13) hydrocarbon fractions was formulated and degraded with Bio-fAEG, a bio fouling assessment model that defines degraded fuels for performance simulation and analysis, predicts biodegradation rates as well as calculates the amount of water required to initiate degradation under aerobic conditions. The degraded fuels were integrated in the fuel library of Turbomatch (v2.0) and a twin shaft gas turbine was modeled for fuel performance analysis. The results indicate a significant loss in performance with reduced thermal efficiency of 1% and 10.4% and increased heat rate of 1% and 11.6% for the use of 1% and 10% degraded fuels respectively. Also parameters such as exhaust gas temperature and mass flow deviated from the baseline data indicating potential impact on engine health. Therefore, for reliable and safe operation, it is important to ensure engines run on good quality of fuel. This computational study provides insights on fuel deterioration in gas turbines and how it affects engine health.