In a classic life-cycle energy analysis performed by Martin B. Hocking, professor of chemistry at the University of Victoria in British Columbia, Hocking compared three types of reusable drinking cups (ceramic, glass and reusable plastic) to two types of disposable cups (paper and polystyrene foam). The energy required to manufacture reusable cups is vastly larger than the energy required to manufacture disposable cups. Consequently, a reusable cup has to be used multiple times in order to recoup the energy investment. Reusables require additional energy and resources to wash the cup between uses; the efficiency of the dishwasher greatly impacts the amount of energy used.

The Hocking study developed the following matrix to show the number of uses necessary to break-even with disposable products

In other words, a ceramic mug must be used 39 times to equal the energy use of a paper cup and 1006 times to equal that of a foam cup. To draw a further conclusion from this chart, the foam cup is much less impactful in its energy use than the equivalent paper product, by as much as 25 times.