Implementation of Spreadsheet Modeling to Compare the Annual Energy Performance and Cost of Microgeneration Systems

This paper presents the investigation of energy and cost saving of microgeneration systems which consist of conventional, load sharing, renewable energy and hybrid-renewable energy systems application featuring single detached house and office buildings by implementing spreadsheet modeling. Microsoft excel is employed as the spreadsheet application in this study. The system performance of each case is calculated under typical weather of ottawa, canada. These cases are calculated and analyzed in terms of thermal/cooling load （building demand） and natural gas/electricity consumption （energy supply） as well as the financial part by involving several parameters which are initial cost, annual energy consumption cost, annual operational and maintenance cost, inflation rate, and return on investment. Moreover, a house and an office have the same geometry of 200 mE. Total of seven cases modeling are developed; Case-1- a house with boiler and chiller, Case-2- an office with boiler and chiller, Case-3-a simple sum of Case l and Case 2, Case-4- a load-sharing model, Case-5- a load-sharing with GSHP （ground source heat pump）, Case-6- a load-sharing with ground source heat pump-fuel cell hybrid system （FC-GSHP）and Case-7- a load-sharing with GSHP--photovoltaic hybrid system （PVT-GSHP）. As the results, it will be observed the efficiency of the load-sharing, renewable energy, hybrid-renewable energy implementation comparing to the conventional system.

Analysing Different Microgeneration Systems for Portuguese Residential Sector

The main purpose of this article is to perform a technical-economic analysis of different microgeneration systems （photovoltaic and wind turbine systems） that can be installed in a single-family house. One of the strategies for improving energy performance of buildings is the installation of microgeneration systems. This will enable Portugal to meet the goal regarding the share of renewable sources on gross final energy consumption imposed by the European Commission climate change and energy package for 2020. The analysis of four different micro-generation systems will take into account the local availability of renewable resources and market technologies and the new Portuguese law concerning microgeneration to promote renewable energy sources in households. The Portuguese microgeneration legal framework is also highlighted.

Economic Feasibility Evaluation of the Use of Wind Microgenerator in Multifamily Building in Southern Brazil

There is a growing worldwide interest in the potential of using existing buildings to generate their own energy as a way to alleviate problems related to the exhaustion of energy resources,environmental degradation and the constant increase in energy-related prices.Among the distributed electricity generation solutions on the market today,wind energy can be a solution for many existing city buildings worldwide.Thus,the objective of this article is to investigate the economic viability of generating wind energy in a multifamily building located in Southern Brazil,(city of Passo Fundo),seeking to supply the condominium electric energy for the period of one year of consumption with a renewable source.To this end,the energy demand of the condominium and the energy generation of the wind turbine were taken into account to calculate the economic viability of the system.The results showed a positive NPV(net present value)demonstrating the economic feasibility of carrying out such an investment.The IRR(internal rate of return)was 15.22%and the return on investment(payback)occurs in 7.88 years.

Analysis by Indicators Performance of the Conceptual Structures mCCHP-SE Using Renewable Energy Sources

This paper refers to an integrated mCCHP （micro-combined cooling heat and power） systems dedicated for isolated residents with energetic independence. The only energy sources are wood pellet and solar energy. The proposed trigeneration system is based on mCHP （micro-combined heat and power） unit with Stirling engine, photovoltaic panels, thermal solar collector and pellet boiler. The proposed mCCHP system utilizes the exceeding amount of heat in the summer for producing the necessary cooling. A residential building with known energy consumption is determined load curves that must be covered by mCCHP system. The paper analyzes four structures of trigeneration systems with thermal activation chiller and two structures of trigeneration systems with mechanical compression chiller. Performance indicators are determined based on energy balance equations for each variant. It compares the performances and establishes the best option.

Multi-conductor Line Models for Harmonic Load-flow Calculations in LV Networks with High Penetration of PV Generation

Low-voltage(LV) distribution networks are unbalanced and present loads with nonlinear behavior, which introduce harmonics in the networks. The predictable increase in photovoltaic microgeneration(PV μG) accentuates this unbalanced characteristic, as well as poses new technical problems,namely voltage rise and reverse power flow. To accurately account for the distributed PV and loads in the LV network, unbalanced three-phase power flow algorithms should be utilized,where different approaches may be used to represent lines with various degrees of accuracy. The more accurate algorithm considers the electromagnetic coupling between the line conductors,whereas the simpler algorithm represents each conductor of the line as a single-phase line with pure resistive behavior. This paper aims to analyze the influence of the line model on the load flow in a highly unbalanced LV network with a high penetration of PV production, and considers the impact of the harmonics produced by nonlinear loads. Based on the results obtained,it is possible to identify the most suitable model to be used, depending on the study to be performed. Different scenarios of PV generation and loads are addressed in this paper.