Our history and future: Vicinity Energy in Philadelphia


Vicinity Energy, a trusted and reliable provider of district energy solutions, has a deep-rooted history in Philadelphia. District energy has been an integral part of the city’s energy infrastructure for over a century, evolving alongside the city of Philadelphia’s growth and development.

District energy’s early beginnings in Philadelphia

Philadelphia’s district energy system dates back to 1889 when the Edison Electric Light Company of Philadelphia—which later became part of the Philadelphia Electric Company—generated and sold electricity from its central facility at 908 Sansom Street. The company created an additional source of revenue by using exhaust steam from the facility’s engines to provide heating to a nearby house at 917 Walnut Street.

In 1903, a year after several local electrical companies consolidated to form the Philadelphia Electric Company, the company opened the first large-scale, centralized power facility in Philadelphia, the Schuylkill Station. Located at the intersection of Christian Street and Schuylkill Avenue, the facility’s original boiler house consisted of forty boilers powered by coal, which arrived by barge up the Schuylkill River.

Over the years, Philadelphia Electric Company made various updates to the facility to keep up with the increasing demand for electricity and different kinds of electricity used for various applications. In 1911, due to the demand for 25-cycle electricity to supply the street railway system, a frequency changer substation was installed to convert 60-cycle to 25-cycle.​ A year later, due to rapidly increasing demand for the 60-cycle system, the company’s transmission voltage had to undergo a material increase from a 6,000-volt two-phase system to a 13,200-volt three-phase system. In 1917, a 20MW 25-cycle turbine generator was installed.

As demand for both 60-cycle and 25-cycle electricity continued to increase, a new facility was built alongside the original Schuylkill Station. This new facility, known as Building A-2 at the time, ​housed a 35MW 60-cycle turbine generator—the world’s largest at the time—and a 30MW 25-cycle turbine generator.

In 1937, the ever-increasing need to supply Philadelphia with more 60-cycle power facilitated another major expansion at the station.​ Two 1250 pounds per square inch (psi) boilers were installed, superimposed over the existing equipment.​ The original 40 boilers in the station were removed, and a 50MW turbine generator was installed. This was a non-condensing turbine, which exhausted steam at 230 psi. The generator was also hydrogen-cooled, an innovative and efficient solution at the time.​

As the Philadelphia Electric Company built other steam-generating facilities, like Willow Street Station, and developed its energy infrastructure, the company constructed a vast underground network to serve various buildings around the city with steam. The system became the third-largest district steam heating system in the United States. In 1950, Schuylkill Station was integrated into Philadelphia’s steam distribution network and eventually became the predominant steam supply. In 1957, 908 Sansom Street was rebuilt as a steam facility with additional boilers installed over the years. In 1997, a 163MW combined cycle plant, known as the Grays Ferry facility, made up of a 118MW gas turbine and 45MW steam turbine, was installed to efficiently provide 1.4 million pounds per hour of steam, displacing the existing 1937 generator and boilers.

A rich history of fuel switching

While coal was used as the steam facilities’ primary fuel source, the boilers were converted to oil in 1937 and later used natural gas. Today, Vicinity’s Grays Ferry facility relies on the efficient combined heat and power (CHP) process to generate heat and electricity simultaneously. Vicinity also leverages LR100 biogenic fuel, waste cooking oil discarded by the local food service industry, to generate steam​ while pushing the clean energy transition, reducing greenhouse gas emissions, and improving local air quality.

How district energy supports Philadelphia today

Since Vicinity’s acquisition of Philadelphia’s district energy system in 2020, we have made significant investments in the infrastructure to improve reliability, resiliency, and efficiency. The Grays Ferry cogeneration facility serves over 72 million square feet of building space with steam, including notable landmarks such as the Walnut Street Theatre, 2 Liberty Place, and Jefferson Health.

The Grays Ferry cogeneration facility demonstrates our impact on the local energy landscape. By generating steam transported through a network of 41 miles of underground pipes, we provide heating and cooling to various Center City office buildings, healthcare, life science, and university campuses.

Our commitment to reducing greenhouse gas emissions is evident in the Grays Ferry facility operations. The district energy system has achieved an annual reduction of nearly 300,000 tons of greenhouse gases, equivalent to removing almost 65,000 cars from the roads yearly. This commitment to sustainability aligns with the City of Philadelphia’s broader climate goals and positions district energy as a critical solution in shaping the city’s clean energy future.

Electrification plans for Vicinity’s Grays Ferry facility

Our plans to electrify Grays Ferry demonstrate our commitment to sustainability and support for the city’s climate goals. To further reduce greenhouse gas emissions, our carbon-free eSteam™ solution integrates renewable energy sources like wind, solar, and hydro and innovative technologies, including industrial-scale electric boilers and a heat pump complex to reduce the facility’s reliance on fossil fuels. Additionally, we plan to investigate thermal energy storage to optimize energy usage, lower costs, and increase efficiency.

Electrifying our Grays Ferry facility will substantially decrease the carbon emissions associated with steam production, aligning with Philadelphia’s goal of achieving carbon neutrality by 2050.

By engaging and partnering with local stakeholders, including government agencies, customers, community groups, and other organizations, we ensure we align with our customers and the city and community sustainability goals. These collaborations will help address potential challenges and identify opportunities for further improvements to contribute to a cleaner, greener Philadelphia for future generations.

Learn more about our electrification plan in our white paper.

Vicinity Energy White Paper - Revolutionizing Urban Sustainability

Michael Ancona

An experienced professional with a background in operations management, Michael Ancona is currently serving as Operations Manager at Vicinity Energy’s Grays Ferry facility in Philadelphia. He writes about topics related to electrification and operations management.