4. Sizing

Storage sizing is a key point in the design of a rainwater harvesting system. On the one hand, the performance of the system will be largely determined by the correct sizing of the storage, since undersized storage is synonymous with mediocre performance. On the other hand, storage is the main item in the cost of a system, so unnecessary oversizing is synonymous with additional costs that could have been avoided. Determining the "right" size is therefore an important issue. It is therefore appropriate to begin by outlining the general philosophy behind sizing a storage tank for rainwater harvesting (§ 4.1 ...