Yale Environment 360
In 1836, Philadelphians mostly used whale oil and candles to light their homes and businesses. That year, the newly formed Philadelphia Gas Works caused a stir when it lit 46 downtown street lamps with gas made from coal in its plant on the Schuylkill River. By the end of the Civil War, public thoroughfares and private dwellings in the core of most large Eastern cities were illuminated by gas, supplied through cast iron pipes buried beneath the busy streets — and the whale oil lighting industry was nearly dead.
Philadelphia’s own pipe network has expanded over the past 185 years to encompass 6,000 miles of gas mains and service lines. But today, Philadelphia Gas Works (PGW) — the largest municipal gas utility in the country — is the incumbent business staring down existential threats, facing challenges from new technologies, upstart rivals, and a quickening 21st-century energy transition that aims to convert many buildings from gas to electricity.
In recognition of these forces and the city’s own climate action plan, Philadelphia has commissioned a “diversification study” to find a new low-carbon business model for the nation’s oldest gas utility, which delivers natural gas to 510,000 customers.
Several states have already begun formally planning their long-term transition away from natural gas. Last June, the attorney general of Massachusetts petitioned the state’s utility regulators to investigate how to transition away from natural gas. Spurred by their own climate action goals, California and New York have launched similar efforts. New Jersey’s Energy Master Plan has set a goal of electrifying 90 percent of buildings’ heating and cooling demand by 2050.
The menu for building decarbonization includes heat pumps powered with renewable electricity, geothermal systems, hydrogen fuels, and biogas generated from organic waste. Some of these solutions are in the early stages of development and deployment. Air-source heat pumps are the most mature technology, with decades of use in parts of Europe and Japan, and in the U.S. South, where heat pumps make up more than 20 percent of building heating systems. A few gas utilities are experimenting with blending hydrogen into their gas mix and testing how appliances handle it, in the hopes that “green hydrogen,” created with renewable electricity, will help them wring the carbon out of their operations.
And Eversource, New England’s largest energy utility, is partnering with Home Energy Efficiency Team (HEET), a Massachusetts-based nonprofit focused on cutting emissions from the building sector, to build an innovative pilot geothermal district heating and cooling system in the Boston area this summer.