Repurposing and reusing existing equipment is one of the many reasons at the heart of a recent proposal to convert a coal boiler to run on natural gas at the Samuel A. Carlson power plant in Jamestown.
"In the past projects, we've been asked why we were building something new," said John Zabrodsky. "With this project though, we're repurposing and reusing. A new building isn't being built. This is a way to utilize what we already have and do it cost-effectively."
Currently, the Samuel A. Carlson power plant relies on its LM6000 natural gas turbine for much of its generating capacity. There are several coal boilers, but due to emission standards, the coal boilers are seldom run.
"If the LM6000 isn't available in many of the months of the winter season, or even a peak summer period, we're concerned about the import limitation at Dow Street from a transmission standpoint," said David Leathers. "We want something as a back up to take our peak and shave it down a little bit. We don't want to add burden right now to the Western New York grid. National Grid has several projects that they're trying to get done in the next three to five years that will strengthen that grid."
Currently, the BPU purchases 73 megawatts of electricity from the New York Power Authority. This energy is used to partially supply the 100 megawatt peak the BPU requires during peak months. The LM6000 natural gas turbine is used to provide additional competitively-priced electricity as it is needed.
According to Leathers, the BPU has looked at several projects in the 10 megawatt capacity range, but found it difficult to justify many of them because they would have cost too much.
"Natural gas is the one thing that we could justify," said Leathers. "Many other fuels aren't economically justified right now. We are a little tentative in putting in new generation that's natural gas, so I think that we'll continue looking at fuel diversification moving forward. We needed a bridge from a reliability standpoint and this is a really good idea to get us there without spending $20 million or $30 million."
The estimated cost of the boiler conversion is roughly $2.2 million. Through the New York Independent System Operators, the BPU receives payments for its generation capacity. The payments for the estimated 12 megawatt output of the converted boiler should pay for the project over 10 years.
"Even if we never run the project, other than to do semi-annual testing for NYISO, those payments should justify the project," said Leathers.
According to Zabrodsky, the conversion was recommended as a part of a consultant's report for the BPU due to two issues in the western part of New York state. The first issue is that power generation is threatened in locations like Dunkirk, due to the fact that the plants are fueled with coal. The second is the strain that is placed on the grid in Western New York.
"Given the industrial base that we have here in this area, we certainly need to have the reliability that we're talking about," said Zabrodsky.
Decisions regarding the process of converting the boiler are expected to begin at the February BPU board meeting. By that time, the board will have a better understanding of the budget and the details surrounding the boiler, as well as preliminary feedback on the permitting process for the boiler. Although the permit may not be issued until May or June, there should be enough indications by February to begin moving forward with the project. If construction goes as planned, the converted unit should be available to be used for the 2013-2014 winter season.
Without the converted boiler, the generating capacity of the plant would drop to between 40 and 43 megawatts, which is the peak production capacity of the LM6000 natural gas turbine. When run in a combined cycle with the converted boiler however, the plant should have the ability to generate as much as 70 megawatts of power. Despite this extra capacity, it is still below the peak native load of the BPU system, according to Zabrodsky.
"We have three coal boilers that are still able to function, but one boiler will see the end of it's life at the end of 2013, and the other two have a likely end of life at the end of 2014," said Leathers. "The coal units aren't running for the most part right now anyway because of economics. The price of coal stayed up and the price of gas went down. We run what is, in essence, our most cost-effective generator."
According to Zabrodsky, coal prices have remained high because of the need for coal in the manufacturing process of steel.
"We intend to look at this on a continuous basis over the next two or three years to see if there's other generation that becomes justifiable," said Leathers. "This gives us some reliability and back-up, though. It keeps some components of the current plant operational, too. It's not a lot of megawatts, but it still gives us some buffer. It's not a high cost compared to the other options that we looked at. It more or less pays for itself even if it doesn't run. You have to ask yourself, why wouldn't you do this?"