Cost analysis model for catalytic conversion of syngas in to light hydrocarbon gases

Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.The economic feasibility becomes one of the greatest issues when we apply this new technology.Evaluation of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift modes.The objective of this study was to evaluate the unit cost of biofuel products(Liquid HCs,Light HCs and Oxygenates CxHyOz)under different capacities using a modeling method.The cost analysis model was developed using Visual Basic Microsoft 2008,computer programming language and mathematical equations.The modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of facilities.As the facility capacity increased from 65 to 10,000 N m^3 h^-1,the biofuel production unit cost of gas(Light HCs),oil(Liquid HCs),and aqueous(Oxygenates CxHyOz)decreased from$38.92 per MMBTU,$30.89 per gallon and$25.74 per gallon to$2.01 per MMBTU,$1.59 per gallon,and$1.33 per gallon,respectively.The results of the sensitivity analysis showed that feedstock cost was the most sensitive cost factor on unit costs for all biofuel products at high capacity.The cost analysis model developed in this study could be used to optimize production unit costs of bio-fuel products from bio-gasification facility.

Quantitative Analysis of Multi-Recovery-Based Intrusion Tolerance Model

Quantitative analysis has always been a difficult problem in security analysis of intrusion tolerance systems. An intrusion tolerance model based on multiple recovery mechanisms is introduced in this paper and how to quantify the security attributes of the model is proposed. A state transition model with recovery states more accurately describes the dynamic behavior of the system. Considering that recovery mechanisms have a great impact on the security performance of the system, we set up the cost models corresponding to different recovery mechanisms. We propose a feasible security measure based on mean cost to security failure in order to evaluate the system cost during the recovery phase. The experimental results confirmed the feasibility of the proposed methods.

Analysis of value of flexibility in Japan’s power system with increased VRE

The growth of renewable energy has accelerated globally toward a low-carbon economy since the Paris Agreement entered into force in 2016.As a result of the increase of variable renewable energy(VRE),namely solar PV and wind,power systems require more flexibility from conventional power plants with less power generation to regulate increased variability.There are sources of flexibility other than conventional power plants,including enhanced power networks,storage capacity and demand response.To maximize economic utilization of VRE power generation,it is necessary to use the flexibility potential from all these sources.In Japan,the share of VRE has increased since the introduction of a feed-in tariff(FIT)and,in parallel,power market reform is underway.Japan has a unique power system of nine grids connected like a fish bone,making the uptake of an increasing share of VRE challenging.This paper assesses the value of flexibility by source in Japan’s power system in 2030.An analysis of different VRE scenarios is undertaken based on a newly developed production cost model.The result of the simulation shows the quantitative impact of each source of flexibility to the generation cost and VRE curtailment and demonstrates the mechanism by which flexibility works to impact VRE curtailment.