In late 2018 we performed the most detailed techno-economic modelling of solar and battery systems in Tasmanian conditions ever undertaken.
The results and recommendations
Here are some articles that go into some of the details of our research:
- Solar basics
- How does solar panel orientation affect performance in Tasmania?
- Which tariff should I use?
- The biggest and cheapest battery you didn't know you already have!
How we did the modelling
We examined actual electricity consumption data from 60 households in greater Hobart from one of our past projects. Energy was logged on each individual heater, the hot water system, and the house as a whole. It was logged every 10 minutes for more than a year. In total this gave us more than 100 million data points. We selected to use as case studies the 4 households that were most different to one another in terms of overall energy consumption, and daily consumption patterns (i.e. daytime vs night time usage). This enabled us to test our findings to see if they held for markedly different load profiles. For some findings we dived deeper, repeating the analysis on up to 36 households.
For modeling solar panel systems we used solar insolation and temperature Typical Meteorological Year (TMY) data at 30 minute time steps. These data sets were developed using data purchased from the Australian Bureau of Meteorology from the 1990s up to the end of 2013. The specific site in question was the Hobart airport. We fed this data into Homer Grid, a sophisticated solar modelling software package, along with the latitude and longitude of Hobart airport so that the sun’s position could be calculated accurately.
We also modeled the precise rates for tariffs 31 and 41 (the tariffs that the vast majority of Tasmanian households are on) and 93 (the relatively new time-of-use tariff), along with current market pricing for solar panel and battery systems.
Finally we ran hundreds of thousands of scenarios for various system sizes, orientations, and load profiles, and analysed the results.
For hot water system modelling, results were exported from Homer Grid and imported into Excel to simulate the effects of timers and solar diverters. This modeling was performed by our Executive Officer, Todd Houstein, who has 3-years postgraduate research experience in techno-economic modelling and optimisation of energy systems, plus 12-years of experience further developing his knowledge and skills with Engineers Without Borders Australia and Sustainable Living Tasmania.