How WSSC Water Gets the Biggest Return for Digester Gas Energy

As part of WSSC Water's (Laurel, MD) BioEnergy Program digester gas will be upgraded to renewable natural gas (RNG). While many wastewater utilities consider RNG projection as non-core business and therefore outsource or 'public-private-partnership' the subcontracting, operation, and maintenance of these activities; WSSC is contracting, negotiating, and managing the entire RNG/RINs program in-house. This presentation will discuss three aspects of the RNG program scheduled for start-up in the first quarter of 2024: 1) Equipment start-up and pre-injection gas quality testing prior (allowed) injection to the WGL pipeline; 2) Actual trades, revenue, and cost for selling RNG to Montgomery County Transit and RINs to a yet-to-be-identified obligated party (refinery); and 3) An updated summary of program economics based on these first actual transactions (that WSSC administers in-house, so as to maximize the net return to their rate base). It is believed that the details of each of these will be of tremendous interest to other utilities considering digester gas upgrading to RNG for transportation fuel uses and RIN revenue. Additionally, the firsthand accounts of equipment commissioning, and mandated gas testing (and possibly test failures and associated responses/equipment tuning/adjustments) will be very informative. The sum total of which will hopefully encourage other utilities to administer these projects themselves and clear up the 'blurry opaqueness' offered by vendors, public-private-partnership (P3) contractors, and other third parties who stand to make all the profits themselves by delivering turn-key projects/programs and taking the unknowns out of wastewater utility's responsibility. The most recent program accounting (without financing) projects WSSC net revenues of between $1,200,000 and $4,800,000/year (at RIN prices of $1.00 to $3.50/D3-RIN). Which compares very favorably to a net operating cost of roughly $500,000/year had they instead used a conventional P3 to deliver the same project. If the costs of WSSC's bond financing are considered, WSSC revenues are reduced to between $300,000 and $3,800,000/year. But P3 costs would increase even more to $3,500,000/year (including P3 financing of the gas upgrading system and associated infrastructure and WGL's financing of the RNG 'gate station'). As a further point of clarification, none of these values include grant funding obtained by WSSC that would have made (and did make) all presented economics more attractive.