Perpetuation of Partial Transformities through Sequential Analyses for Refined Emergy Accounting and Index Development

An elegant feature of emergy synthesis is its capability to integrate the diverse inputs required to operate a system into a single metric that represents the equivalent amount of energy of one type. However, integration also presents problems with 1) precise tracking of emergy flows from source to sink, 2) developing and estimating indices, 3) communicating results to non-emergy specialists, and 4) advancing an emergy theory of recycle. Conventional emergy analyses collapse solar transformities into a single value, which are subsequently used in more emergy calculations. While this eases the accounting process, it loses information regarding how much emergy is contributed from different categories (e.g., how much renewable emergy is there in human service?). We propose that the emergy of all inputs be partitioned into categories that correspond to their ultimate geological or meteorological basis and that this partitioning be perpetuated through the entire emergy evaluation. That is, the emergy of an item should be partitioned into: renewable environmental (R), non-renewable environmental (No), non-renewable minerals (Nm), non-renewable, non-petroleum fuels (Nf), and nonrenewable petroleum (Np). A partial transformity is defined as the emergy of one category of input required to make a product per the total energy available in the product. The method improves the precise estimate of the contribution of renewable, non-renewable and purchased inputs, allows for new index development, offers a new basis for communication, and may encourage more theoretical work on the emergy of recycle. We demonstrate the method with an example of producing ethanol from cellulose and offer a preliminary list of partial transformities for a few basic resources.