Electric Generation Technologies for District Energy

The configuration at the University of Arizona is typical of many district energy systems: A
central plant generates electricity, recycles the thermal energy for cooling (or heating), and
distributes all the outputs to other buildings in the network. (Photo courtesy of GLHN)

Not all district energy systems include electricity generation - some are just heating, just cooling, or a combination of heating and cooling. But quite frequently, district energy systems do include an electricity component - especially all newer systems. The efficiency of the entire system yields very attractive electricity costs for all buildings connected to the system.

The prime movers for electric generation are similar to those used for combined heat and power (CHP). The main distinguishing factor is size - district energy systems can be quite large sine they supply a number of buildings. The most common prime movers for district energy are gas turbines, steam turbines, and large reciprocating engines. While fuels cells and microturbines could be used, their smaller size means they would need to have many units banded together, or be used in combination with one of the above larger technologies.

Gas Turbines

Steam Turbines

Reciprocating Engines

Next: Fuels for District Energy
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