When lighting was proposed for Hartford's streets in the 1840s, some citizens were concerned that it would encourage people to stay out late at night, thereby making them susceptible to criminal activity and illness. Night and day, they said, were part of the natural law and should not be tampered with by artificial devises such as gas lamps. However, other Hartford citizens wanted Connecticut's second largest city to install gas lighting as other eastern cities were doing at that time. The result was that several of the city's leading men were granted a charter by the Connecticut General Assembly under which they formed the Hartford City Light Company, one of the community's first public utilities and a forerunner of the Connecticut Natural Gas Corporation.

The founders' original investment of $100,000, a very large amount for that period, was used to lay five miles of mains in Hartford and to build a plant on Front Street which could distribute five million cubic feet of manufactured gas. As Hartfordites changed their lighting habits from whale oil lamps and tallow candles to gas lamps, the new Company expanded steadily and throughout the 19th century added property and new facilities to meet the increasing demands of both individual and industrial consumers in Hartford.

In the 1890s electricity was introduced as a competitive source of lighting. Hartford Gas realized the need to develop new markets and uses for gas. While expanding its fuel distribution system into West Hartford and Wethersfield in 1899 and East Hartford in 1907, the firm successfully promoted gas as an efficient fuel for water heating and cooking. Thus, even though its primary market was changing, Hartford Gas was able to maintain uninterrupted growth throughout the period as illustrated by the move in 1905 of its main offices to larger spaces at 565-67 Main Street. There the latest gas appliances were displayed for the potential buyer.

The new century brought the acquisition of the south Manchester Light and Power and Tramway Company, the construction of a large service building, the extension of gas lines into Glastonbury and Bloomfield, and another move of corporate offices to 233 Pearl Street in 1928. The Company would remain there for more than 50 years.

A major change for Hartford Gas had taken place by 1959 when the company converted from supplying manufactured gas to supplying the natural fuel to customers through pipelines from the fields of Louisiana and Texas. The construction of a steam and chilled water plant in 1961 was also a significant step in the firm's expanded service as well as an early effort to enhance the environment. This facility, the first investor-owned plant of its kind in the world, provided year-round climate control service to downtown Hartford's buildings, eliminating the need for construction of several boiler plants with their resulting pollution. Ten years later another first was accomplished when the Company introduced an experimental natural gas fuel cell home; this also reduced pollution and saved natural resources at the same time by using natural gas to produce electricity as a power source. The next year marked the completion of a liquefied natural gas plant, which provided storage for over one billion cubic feet in a liquefied state ready for use when needed during cold.

Through the seventies and eighties CNG continued to accept and use advances in technology as a means to improve service to customers and to promote growth in gas sales. Energy conservation and supply were important consumer issues following the Arab oil embargo of 1973-74. Natural gas became better known for its domestic and dependable sources. Manufacturers of gas powered equipment greatly improved fuel efficiency. CNG customers eagerly replaced old appliances with highly efficient gas furnaces, boilers and heaters.
In the late eighties, the Company, through its subsidiary, Energy Networks, Inc. converted its district heating and cooling operations from boilers to more efficient cogeneration (heat reclaiming) technology. CNG's steam and chilled water plant became the most modern in the country and the largest cogeneration powered district heating and cooling system in the world.

In 1990, CNG further positioned itself for continued growth. The Company became a part owner of the Iroquois Gas Transmission System, a pipeline that transports gas from Canada. This was to assure an adequate supply of gas for the increasing energy demands of customers- giving CNG greater control over supply, capacity and price. The Iroquois Pipeline, completed in 1992, transports Western Canadian gas to the New York, Connecticut and New Jersey markets and provides yet another cost-effective supply of natural gas to the region.

Emerging computer technologies substantially increased productivity and forever changed the way CNG conducted business. A computer aided dispatch system came on-line in 1991, virtually eliminating paperwork in the field and saving time and work for field personnel. It was the biggest technological improvement ever to take place in the Company's customer service operation.

On June 30, 1999, CTG Resources, the parent company of CNG, announced a merger between CNG and Energy East. Energy East is an energy delivery, products and Services Company doing business in New York, Massachusetts, Maine and New Hampshire. The combination of these two companies has enhanced and strengthened CNG's commitment to its customers to provide the best in service and reliability.

The present strength of Connecticut Natural Gas grew through pioneering efforts in areas unimagined in 1848. The Company has always had the courage to try new technologies, which today provide the most efficient service at the lowest possible price for the customers of Connecticut Natural Gas Corporation.