The modified ESP has performed better than the original ESP at a lower power use. I demand of the original ESPs. Total internal plate area is less than one-half that of the original ESPs, tending to lower capital costs. The lower efficiency was attributed to higher post-retrofit flue gas O 2 and higher stack temperatures which accompanied the air heater retrofit. The heat pipe was tested in accordance with ASME Power Test Code for Air Heaters 4.3.
Air infiltration is low for both heat pipes.
Economic Performance Economic data are not yet available. The space-saving design features of the technologies, combined with the production of marketable byproducts, offer significant incentives to generating stations with limited space.