The Top-Ranked Battery in Maryland’s Storage Program Is Planned for Dickerson. RWE Pulled It From the State Program.

The battery project that ranked highest in Maryland’s first solicitation for large grid batteries under the Next Generation Energy Act is planned for the former Dickerson coal plant in western Montgomery County. It is not among the winners. RWE Supply & Trading Americas withdrew its 300-megawatt Fourth Quarter battery from the competition on Aug. 28, and when the Maryland Public Service Commission ruled on Oct. 1, it conditionally awarded credits to two other projects totaling 440 of the 800 megawatts it had set out to buy.

RWE’s one-page notice of withdrawal does not give a reason beyond this sentence: RWE “has decided to pursue an alternative path forward to construct and commercialize the Fourth Quarter Project as planned.” The notice, filed by RWE attorney Brian M. Quinn of Venable, places the project “at the 230 kV Dickerson Substation at the former Dickerson coal plant in Montgomery County.”

The commission, in its Oct. 1 order, said it was “disappointed” that RWE and Pulaski Energy Storage withdrew, noting that both offers had positive benefit-cost results and projected net savings for ratepayers. The order adds that “Maryland will still reap the energy storage capacity benefits” because of RWE’s stated plan to build the project anyway.

What the state’s evaluation found

The commission’s consultant, Power Advisory LLC, scored all five applications. In Order No. 92667, the commission wrote that “RWE’s Fourth Quarter BESS Project 300 MW Application consistently ranked highest with a score range of 93.86 – 96.93,” ahead of the Pulaski project (82.35 to 87.53) and Chalk Point (82.04 to 83.94). The range reflects different weightings of quantitative and qualitative scores, from 80/20 to 60/40, and the ranking did not change under any of them. The order’s scoring table shows the Dickerson project with both the top qualitative score and the top quantitative score.

The state’s modeling projected the Dickerson battery would save Maryland residential customers more than any of the other four projects. The order lists a levelized net credit of $10.35 per Maryland residential customer over the project’s life. At the commission’s request, Customized Energy Solutions, which worked on the evaluation with Power Advisory, converted that to savings of 5.81 cents per month. The only other project projected to save customers money, Pulaski, came in at 0.57 cents a month. The two projects the commission chose carry projected net costs: 4.45 cents a month for Chalk Point and 2.53 cents for Jade Meadow III, or 6.98 cents a month combined.

The Maryland Office of People’s Counsel, the state’s utility consumer advocate, argued that the consultant’s model likely overstated benefits to ratepayers and applied its own, more conservative adjustments. In its Sept. 11 reply brief, the People’s Counsel wrote that the Dickerson project “was the only project that, after applying the conservative adjustments recommended by OPC witness Michael Freeman, had projected benefits that exceeded projected costs.”

Commission staff also backed the Dickerson battery in its initial brief, filed Aug. 28, the same day RWE withdrew. Staff’s first recommended option, as summarized in the order, was the Dickerson project plus the 400-megawatt Chalk Point project, a 700-megawatt package that “provides the strongest combination of economics, readiness, and modeled customer benefit.”

What the commission chose instead

The commission conditionally awarded 15-year credits to the 400-megawatt Chalk Point Storage Project in Aquasco, Prince George’s County, at the existing Chalk Point power plant site, and the 40-megawatt Jade Meadow III Battery Storage Project in Barton, Garrett County, on a reclaimed coal mine, according to the commission’s Oct. 1 announcement. Another applicant, the 135-megawatt Pulaski project in Baltimore County, withdrew on July 2. The commission found the 500-megawatt Oystercatcher project in Harford County not cost-effective and did not select it. It also turned down Chalk Point’s late offer to expand to 535 megawatts.

The trade outlets mgrid and pv magazine USA reported the shortfall in early October, and mgrid reported on Oct. 3 that RWE’s withdrawn project was at the Dickerson site. The commission will issue a second 800-megawatt solicitation on or before Jan. 1, 2027, with those projects expected to begin operating in the fourth quarter of 2029, the order says.

Why the credits matter for electric bills

Under the Next Generation Energy Act, winning projects receive fixed payments called Energy Storage Capacity Credits, which electricity suppliers must buy. The money each project earns in the regional PJM Interconnection capacity market goes to the commission “for distribution to electric companies and customers,” the order says. The order also describes a work group setting up an escrow account to coordinate the credit purchases with “non-bypassable distribution charges that shall be applied to all Maryland electric customers,” a group that includes Montgomery County households.

The order summarizes the People’s Counsel’s warning this way: “Customers would make fixed payments for 15 years, while key benefits depend on uncertain future capacity prices, ELCC values, market effects, and project performance.” The commission itself cautioned that actual bill impacts “will vary from these projections.”

The Dickerson site

RWE’s project page still lists Fourth Quarter as “In development” “on the grounds of the retired Dickerson Generating Station,” with operations anticipated in 2028. The order lists the project’s planned commercial operation date as Oct. 1, 2028. The Power Advisory evaluation says RWE has signed an interconnection agreement with PJM and Pepco. Commission staff testified that the schedule “remains dependent upon” Pepco’s timely completion of transmission work, according to the order.

Bethesda Magazine reported in April that Terra Energy owns the 700-acre former power plant site on Martinsburg Road and advertises it as an “ideal space for data warehouse and battery storage.” Bethesda Magazine also reported in May that Atmosphere Data Centers has proposed a five-building data center campus on a 110-acre parcel of the same property. The County Council approved an 18-month moratorium on data center development on July 28, and Atmosphere was seeking to postpone the Hearing Examiner’s review of its application, Bethesda Magazine reported in August.

Still unanswered

• What is RWE’s “alternative path forward” for the project, and is October 2028 still the target for operation?
• Will RWE bid the Dickerson project, or another Maryland battery, into the state’s second round?
• Outside the state credit program, which state and Montgomery County approvals does the project still need, and has RWE applied for them?
• Where does Pepco’s transmission work at the Dickerson substation stand?
• Does the battery share land, power lines or plans with the data center proposed for the same property?

We have not yet put these questions to RWE, the Maryland Public Service Commission or Pepco; this story will be updated with any response.

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