Beam steam engine, efficiency

Figure 18.1 Barometric condenser improved efficiency of the legendary beam steam engine.

The original steam condensers were barometric condensers, which were used to increase the efficiency of the steam-driven reciprocating beam engines by a factor of 10. The barometric condenser was invented by James Watt (the steam engine was invented by Thomas Newcomen). Exhaust steam is mixed directly with cold water. As this creates a vacuum, the barometric condenser must be elevated about 30 ft above grade. The mixed condensate and cooling water drains through a pipe called a barometric leg—hence the name barometric condenser. 

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