Home based solar power generation, storage and localised grids

This project aims to determine the optimal and cost effective solar powered battery storage system for a Toowoomba resident in a small, medium and large household. The project was initially undertaken through a literature review of solar panels, batteries and microgrids. The background research also consisted of analysing various batteries and solar panels on the market to determine options available for analysis. For the analysis, load profile data of an Ergon Energy customer was acquired. The analysis was undertaken using the program Homer Pro created Homer Energy. The program is specifically designed for modelling microgrids and can evaluate using various architectures including a grid connection, battery storage, PV array and a load. Other options include hydro-electricity, wind power and so on however these are beyond the scope of the project. Homer Pro has access to default solar irradiance and climate data for various locations including Toowoomba and was included in the analysis. The analysis was undertaken for a small, medium and large household. The load profiles for the various hold holds was determined by comparing the actual data received from Ergon Energy and scaling the data according to typical usages based on the Australian Bureau of Statistics and Origin Energy data. From the results, it was found that the optimal microgrid system for a typical Toowoomba household of all sizes is to have a 10kW PV array only. Investigation into the benefits of household PV found that the payback period varies according to household size. The payback period for the small household microgrid is between 12 and 13 years, for a medium household microgrid the payback period is between 10 and 11 years and for the large household microgrid the payback period is between 9 and 10 years. To determine if having a PV array was a more economical option than remaining purely on the grid further testing was undertaken. For this, the evening peak load and hot water peak load for the medium household was shifted to the middle of the day when the power output of the PV array is at its greatest. The previous peaks were lowered to reflect less demand required. The results from the Homer Pro testing found that in both cases the system with a PV array had a lower cost of electricity, net present cost, operating cost and higher renewable fraction than just grid supply. The higher the powered PV the better the economic results. Therefore, it is recommended that for all households to install a high powered PV array