The average pulverized coal-fired coal plant is more than 30 years old and has a heat rate in the neighborhood of 10,300 Btu/kWh operating with an "off-design" coal. Add a high load factor (or increased cycling service), squeezed maintenance budgets, reduced plant stuff, and increased time between overhauls to meet the plant staff, and increased time between overhauls to meet the plant's proforma, and you've got major stress. Fortunately, there is a way to come in under you NOx budget and lower the stress. Breathe deeply and read carefully.