Nelson noted that the gas pipeline to the plant can be subject to curtailments during peak season (winter). To ensure that start up fuel is always available, particularly in light of the new PJM Capacity Performance requirements, the plant installed the world’s largest mobile liquefied natural gas (LNG) system.
“Longview should be the future of coal in this country,” Keffer said. “These plants are relatively low cost, highly efficient, and highly reliable with very low “emissions.”
It is important to note that Longview is a mine‐mouth facility, getting its coal from the Mepco LLC, a mine operation located near to the plant. In fact, Longview was designed to be fully integrated with the mine and to utilize run‐of‐mine coal, a situation that allows Longview to avoid the costs of fuel preparation and large scale storage. Longview gets it coal from the Mepco mine by means of a 4.5‐mile‐long belt line that substantially reduces transportation costs. The conveyor also minimizes the environmental and traffic impacts of trucking on local communities.
Since its commissioning in 2011, Longview has invested another $120 million in improvements both to correct some problems uncovered in commissioning and to ensure reliability.
The improvements have resulted in a very high net plant efficiency of 39.5 per cent. This allows the plant to produce full power using 17.5 percent less fuel than the average coal plant in the US. Alone, this saves Longview over $10 million per year in the plant’s operating cost.
In terms of pollution controls, the plant utilizes the very latest best available control technologies, including low NOx burners, scrubbers, acid mist reduction systems, particulate matter removal achieving up to 99 percent reduction of particulates, SO2 removal using wet flue gas desulfurization systems and Mercury and HAPS removal using MATS compliant AQCS equipment.
As a result, the plant achieves “orders of magnitude reductions” over conventional plants in SOx, NOx and PM emissions. It also achieves a 20 percent reduction in CO2 emissions, according to Keffer.
Operating a more efficient plant means costs and emissions are reduced. Nelson said Longview has the lowest dispatch cost of all coal units in the PJM market.
“We’re cheap. Due to our low cost structure, efficiencies and consolidation with our coal supplier, we’re down with wind and hydro on our dispatch costs,” he said.