Cost-effectiveness of rainwater tanks in a number of Local Government Areas of South East Queensland

Contains a model for estimating the cost-effectiveness of rainwater tanks in South East Queensland (SEQ) covering the regions of Brisbane, Moreton Bay, Sunshine Coast, Ipswich and the Gold Coast. This model runs in the @RISK software package (an application for Microsoft Excel), which uses Monte Carlo simulation to generate a probability distribution of the cost-effectiveness and to undertake sensitivity analysis.

The input variables draw upon recent research in the Urban Water Security Research Alliance which provided data about variables of cost and yield for rainwater tanks in the region. Input variables include:
Capital costs (rainwater tank, the pump, laying of a concrete slab for the tank to rest upon as well as plumbing and installation of both the tank and the pump);
Annual costs (operating costs such as energy use for the pump, maintenance costs such as desludging as well as replacement cycles for pumps and tanks over the period of analysis);
Yield variables (household demand and end use, connected roof area, rainfall pattern as well as the effect of up-scaling from a single rainwater tank to consider the yield of a large number of tanks).

For full details of the model, and references for the data sources used, please refer to: Hall, M. R. (2013). Review of Rainwater Tank Cost-effectiveness in South East Queensland. Urban Water Security Research Alliance Technical Report No. 105.