Combined Cycle, Emissions, Gas, New Projects

Oklahoma Receives 1st M501J Gas Turbine in Western Hemisphere

Grand River Dam Authority (GRDA) received the first M501J gas turbine in the Western Hemisphere Wednesday. The new advanced class gas turbine will be installed at the GRDA’s Grand River Energy Center (GREC) outside Chouteau, Oklahoma. The turbine is the first of its kind in the country, and the only J-Class turbine to be built by Mitsubishi Hitachi Power Systems Americas (MHPSA) so far at its Savannah Machinery Works in Georgia.
Speaking at Wednesday’s press event, MHPS President and CEO David Walsh said the largest gas turbine in 1980 was about 100 MW, making this new turbine about 3.3 times larger than anything possible only a few decades ago. Walsh also said the new turbine emits 67 percent less carbon dioxide (CO2), 96 percent less nitrogen oxides (NOx), and 99.9 percent less sulfur dioxide (SO2) than older coal-fired units.
The M501J turbine has an ISO base rating of 327 MW in simple-cycle operation, and a rated rotor speed of 3,600 RPM. Weighing in at about 320 tons, the 60-Hz machine has a ramp rate of 40 MW per minute, and a startup time of about 30 minutes. In a 1-on-1 combined-cycle configuration, the turbine delivers 470 MW, with efficiency approaching 62 percent. The new J-Series technology fires at an inlet temperature of 2,912 degrees F, about 100 degrees hotter than its G-Series predecessor.
There are currently 18 J-Series turbines in operation around the world, all in the Eastern Hemisphere. In time, existing orders for J-Series turbines will bring that number to 41.
Walsh praised the GRDA and Tulsa Mayor Dewey Bartlett for having the foresight to visit Japan prior to finalizing the sale of the turbine. “Though this is the first M501J turbine in the United States,” said Walsh, “MHPSA has previously built J-Series turbines for power plants in Japan, Korea, and Taiwan. This same machine has run in Japan since 2011. The mayor and the GRDA’s representatives were able to see the turbine in operation, and to speak with Black & Veatch, who helped them evaluate their technology options and ultimately decide for the J-Series.”
Walsh continued by saying the United States now generates 36 percent of its electricity using natural gas, noting that Oklahoma and its surrounding region has more than enough natural gas resources to be self-sufficient.
Tulsa Mayor Dewey Bartlett said the new turbine will allow Oklahoma gas to be used in an Oklahoma turbine, which is operated by Oklahomans to provide clean energy for Oklahomans. Mayor Bartlett further praised the turbine, commenting on the machinery’s tight tolerances and overall quality.
Once the current GREC project is complete, the power plant will operate three units. Two existing coal-fired units have operated at the site for decades. One of those coal-fired units recently underwent environmental upgrades to bring it into compliance with Mercury and Air Toxics Standards (MATS) and other emissions mandates. The other coal-fired unit will be converted to natural gas in the coming years.
Construction of the plant’s 495-MW gas-fired Unit 3 represents the first time in 30 years GRDA has broken ground on a new power plant. Partners on the project include Nooter/Eriksen, who will provide the heat recovery steam generator (HRSG) at the combined-cycle plant. Kiewit TIC will serve as the EPC contractor for the project, with Black & Veatch operating as the owner’s engineer. Hitachi will supply the transformers; Enable Midstream Partners the natural gas pipeline infrastructure.
“A key objective for GRDA and our project partners was to set a new standard in power generation, and to do it right here in Oklahoma,” said Charles Barney, assistant general manager of fuel & generation projects for GRDA. “We’re a relatively small organization, and it was crucial that our project partners shared our goals and strategies.”
To reduce air emissions, GRDA decided to use less coal and invest in cleaner-burning natural gas, Barney said.  
“We decided the lowest cost option was to purchase a new turbine and so benefit from efficiency advances that an older turbine couldn’t provide,” he said.
In addition to the turbine, MHPSA will also supply a 167-MW SRT-50 steam turbine and associated electric generators, for a total equipment cost of $77.8 million. Altogether, GREC Unit 3 is estimated to cost $472 million. The plant is expected to generate enough electricity to power half a million homes at less than $1,000 per kilowatt. Commercial operation is expected in 2017.
“Mitsubishi Hitachi made us an offer we couldn’t refuse. They guaranteed delivery in March, and had it to us in February,” Barney said. “They committed their best people and technology to the project, and came through on those commitments. They also provided capacity, efficiency, and operational guarantees that were superior to GE and Siemens. That’s important for a unit that operates at very high temperatures and pressures.”
Speaking about the turbine following Wednesday’s ceremony, Barney, an engineer by training, said, “It’s gorgeous. The ceramic finish on this new turbine make it a work of art.”