Pros And Cons of the Sterling Engine With anything, there is always a good side and a bad side to it and a sterling engine is not an exception. Pros • Because the heating source is external, the method for heating is very flexible. So the sterling engine does not require an open flame heat source, but any source of heat from nuclear to solar heat. This leads the sterling engine to be fairly flexible.   • With a continuous heat source, emissions are more readably controllable which leads to better emissions. • The pressure in a sterling engine is very consistent and because of this, the engine can be designed to the specific pressure which intern reduces the chance of an explosion that was faced with the steam engines of the time. • Since there is no required air source, a sterling engine is ideal is applications such as submarine and in space. An additional benefit is that a sterling engine can be built to be quiet further aiding the use in submarines. • If a sterling engine is being used to pump water, the water can be used as a coolant and in the process, make a more efficient process. Cons • The initial problem with the sterling engine is that the heat source is external and because of this, the engine requires time to warm up before any power can be produced. • Since the gas is contained with in the engine, the engine itself must be able to resist the temperature and the corrosion. Because of this, the cost material used would increase the cost and the cost of maintenance would increase the overall cost of the engine. • To get the most out of a sterling engine, the temperature difference must be as large as possible. Because of this, the cooling fins on a sterling engine could be quite large and improbable in particular applications. This is a leading factor to why sterling engines are not used in airplanes or automobiles.