Two common examples of activities needed to develop a performance economy are car sharing and electronics take-back (see Box 19.3). Sketch an approximate life cycle system boundary of these activities with and without sharing. Under what conditions would a sharing economy result in a smaller life cycle impact? Consider various practical scenarios and state your assumptions.

Box 19.3:

BOX 19.3 Examples of Activities Toward a Circular Economy Car sharing. The traditional model of car ownership is giving way to a model of car sharing, which has many characteristics of the performance economy. Companies such as Car2Go and Zipcar provide the service of mobility by car without requiring car ownership. Companies like Uber, Lyft, and Ola enable even greater sharing by allowing car owners to have the benefits of ownership and providing others the benefits of sharing. Electronics take-back programs. Several countries have policies that require manufacturers to take back their products at their end of life. A prominent example is the Waste Electrical and Electronics Equipment (WEEE) Directive of the European Union. Many companies have voluntary product take-back programs. For example, Best Buy stores accept products made by many electronics manufacturers. Companies such as Xerox have redesigned their products to enable disassembly, reuse, or remanufacturing after take-back. This includes changes such as reducing the diversity of materials, in particular those that are difficult to recycle; different mechanisms for putting parts together in such a way that they can be disassembled; and choosing recycled and recyclable materials. This bears similarities to the case of the Volkswagen Lupo 3L that we learned about in Box 17.1.