Expanding Energy, Decreasing Dependency

Marine Corp Logistics Base Albany battles toward meeting and exceeding DOD renewable energy goals with expansion of its landfill gas-to-power project and other developments.
By Katie Fletcher | October 31, 2014

In southwest Georgia’s Dougherty County, the 3,600-acre Marine Corps Logistics Base Albany assumes the mission of rebuilding and repairing ground combat and combat support equipment. The base embarked on another mission in 2005 to develop opportunities for renewable energy installations to support what it was already positioned to do. Now, after some completed installations, the base is in the process of boosting those efforts even further.

The renewable energy onset began when a number of mandates were issued to increase energy production from renewable resources. MCLB-Albany contracted with Chevron Energy Solutions to identify renewable energy projects using a Department of Energy Savings Performance Contract, one of the private-sector financing authorities leveraged to meet these goals. “One of the mandates requires us to reduce our consumption—on a MMBtu per thousand square feet (ksf) basis—by 30 percent by 2015,” says Fred Broome, director with the installation and environment division on the base.

Broome says the ESPC task orders and others have allowed the base to meet and exceed that goal. Under the ESPC, Chevron identified eight energy conservation measures (ECMs). One of the ECMs was a project with the Fleming/Gaissert Road Dougherty County landfill across the road from the base. “It’s a great project for us, this (methane gas) is a resource that we would have just been flaring off and now we’re getting a beneficial use of it,” says Scott Addison, Dougherty County solid waste director.

The landfill gas-to-energy (LFGE) project uses gas that was previously vented and flared from a header pipe at the landfill. The landfill gas extraction system includes 140 vertical wells and one horizontal well to provide landfill gas for the project. Addison compares the wells that are inserted with plastic pipes to straws with holes in them. After being vacuumed through the wells, methane gas is sent to a compression skid at the landfill site, which cleans, dries and compresses the gas before sending it via 3 miles of pipeline to a combined-heat-and-power (CHP) plant at MCLB-Albany. Addison says the base pays 75 cents per MMBtu for baseline quality gas, with a 2 to 5 percent increase each year and a 33 percent increase on year five. “The first year we (Dougherty County) received about $122,000 in revenue from the project,” he says.

The gas fuels the CHP plant’s 1.9-MW GE Jenbacher generator and a heat recovery steam generator (HRSG), which recovers heat from the engine stack that produces 95-pound force per square inch gauge (psig) of steam.

Since the plant’s completion in 2011, MCLB has kept expansion under consideration, and is now taking action. The base is capitalizing on space set aside during initial construction by installing a second generator with the capacity of 2.1 MW and an additional HRSG. The HRSG produces hot water (180 to 200 degrees Fahrenheit) for industrial processes at the maintenance center on base, and the second generator should produce enough steam to cover the center’s demand year-round. The $4.5 million expansion, funded under the Energy Conservation Improvement Program Headquarters Marine Corps, will essentially double its renewable energy production capabilities by the anticipated startup date in April 2015. “The thought was that when the first generator was down for maintenance or outages the second generator could run and the renewable energy would not stop,” Broome says. “The redundancy of having two generators helps with energy security on the base.”

Energy security is a driver with renewable energy installations, but as Broome points out, the economics have to make sense. The initial project economics didn’t demonstrate savings on a standalone basis when compared to terms MCLB-Albany had with utility providers. In order to make the economics work, the project was bundled with another ECM, which replaced and upgraded 18,500 light fixtures on the base, and added another building to the direct digital controls system. The 20-year contract was signed with Chevron in December 2009 for it to develop and maintain the CHP plant, pipeline and landfill gas (LFG) processing equipment throughout the life of the contract. The base pays Chevron back with the energy savings gathered from the project. According to Broome, last year the LFGE project had a total cost savings of over $1.5 million, with total energy savings of 48,030 MMBtu.

Economic viability also played a large role when determining if the project supported expansion. The generator at the base is down 14 percent of the year on average for maintenance and routine checks. “When we did the economic analysis for a second generator, we were able to justify it just off of the second generator running when the other is down,” Broome says.

The project has the potential to produce 24 to 40 percent of the base’s load depending on the availability of LFG, and reduce energy use and carbon emissions by 21,160 tons annually. The county landfill currently does not produce enough LFG to run both generators full time simultaneously, but Addison says as the landfill grows, the well field will be expanded to new areas. Until the amount of LFG production and amount required to fuel the generators is determined, MCLB-Albany has several options on how to run the generators. One is running the second generator on natural gas or a blend of natural gas and methane. The GE Jenbacher generators allow dual fueling.

MCLB-Albany doesn’t want to stop with just this expansion. Presently, the base has exceeded the mandated 30 percent by 2015 with a current 41 percent reduction. However, there is also the goal of reaching net-zero by 2020 at half of the bases in the Navy and Marine Corps. MCLB-Albany wants to be one of the first to achieve net-zero, and Broome believes the base is on track to reach that goal by spring of 2017, if all goes as planned. A proposed project that could bring the base to net-zero is through a partnership with Proctor and Gamble and Constellation Energy on a 7.5 to 10 MW biomass project. The base’s location comes at an advantage again, with this project utilizing property near P&G’s paper products plant near the base. Broome anticipates contract signatures in August 2015 with production in spring 2017. “To meet the secretary of the Navy’s goal, short of shutting the lights off, we have to have more renewables,” Broome says. “To get there, we have to have technology that saves money—we cannot put technology in place that does not save money to be green for green sake—it has to be economical.”

Author: Katie Fletcher
Staff Writer, Biomass Magazine