A Stirling engine is another example of a heat engine which could work in the place of our ORC engine. The choice of engine design is motivated by ease of construction (number of machined parts, tolerances, etc.), cost, and complexity of design. Our organization has chosen to focus on the ORC engine as we feel it provides a simpler design that is easier to teach, construct, and maintain. Initial analysis has also shown that the capital cost of an ORC engine will be competitive or lower than that of a Stirling engine for the system sizes we are targeting.