Steam injection seen opening cogeneration for variable-load users

Steam injection technology, in which excess steam is used to increase power output, is of increasing interest to industrial and commercial users whose thermal requirements were previously considered too variable for cogeneration. While these systems can carry 5 to 20% premiums over conventional gas turbine systems, the extra cost can be paid back in three years or less by increasing electricity output with steam that would otherwise be wasted. The three firms now marketing steam injection cogeneration systems describe the advantages of their products. Some question whether the system qualifies as cogeneration because federal law requires that some steam be used for process purposes. There is also concern over the effects of prolonged steam injection on a turbine.