The changes in U.S. electricity supply and usage levels are rapidly reshaping utility load profiles and thus generation and transmission requirements for both new and existing resources.
The recent discovery of relatively cheap natural gas in the U.S. and growing use of the fuel as a baseload power generation source has also coincided with the rapid adoption of renewable resources in many parts of the U.S. These new components of the electricity supply stack continue to displace more traditional and older forms of baseload power generation, coal and nuclear units, for both economic and public policy motivations. Unfortunately, these growing pieces of the U.S. generation supply side all are subject to weather related intermittency.
Turbine inlet air conditioning (TIAC) is a cost effective solution to mitigate weather-induced reduction of output for natural gas generation units. The ability to provide constant output from gas-fired unit will continue to grow in importance given the addition of intermittent renewable resources and the exodus of coal and nuclear units from the U.S. power supply mix.
The future “baseload” resource of choice in the U.S. is natural gas-fired generation which unfortunately carries a level of intermittency due to the ambient air environment (temperature and humidity) in which the plant operates. While the variance in output is not as pronounced (or recognized) as wind and solar generating resources, a gas unit’s operational variability still needs to be addressed, especially given the new composition of the generation stack(s) and the potential for the increased ramp rate implied by the “duck curve”.
The duck curve represents a day with high renewable availability and/or high demand response activity, thus depressing midday energy demand. Then, as the sun goes down and people start coming home from work, energy demand ramps steeply upward, putting pressure on grid operators and generators to ramp up production to meet it. Fortunately, natural gas fired power plants, unlike coal units, have the ability to respond quickly to address this rapid ramp-up in demand. TIAC provides a natural gas fired generating plant with the ability to manipulate inlet air temperature (down or up) in order to perform reliably regardless of ambient air conditions. The removal of weather intermittency/uncertainty for gas-fired units provides both operational and system planning benefits and greater grid reliability.