1. A computing system comprising: at least one computing device having at least one controller, the at least one computing device configured to tune each gas turbine in a set of a plurality of gas turbines based upon a fuel flow parameter and an exhaust energy parameter, wherein the at least one computing device is configured to: command each gas turbine in the set to a respective base load level based upon a respective measured ambient condition; command each gas turbine in the set to adjust a respective actual value of the fuel flow parameter of each gas turbine in the set to match a nominal value of the fuel flow parameter of the set, and subsequently measure a respective actual value of the exhaust energy parameter for each gas turbine in the set; and perform an adjustment to a respective operating parameter of each gas turbine in the set based upon a difference between the respective actual value of the exhaust energy parameter and a nominal value of the exhaust energy parameter at the respective measured ambient condition for each gas turbine in the set, wherein the adjustment to the respective operating parameter of each gas turbine in the set aligns each gas turbine in the set onto a first line in a graphical space plotting the fuel flow parameter versus the exhaust energy parameter, wherein the first line is orthogonal to a characteristic line in the graphical space, wherein the characteristic line is a mean characteristic line of all of the plurality of gas turbines in the set, at the respective base load level of each gas turbine in the set, plotting the fuel flow parameter versus the exhaust energy parameter.