The point at which the electric light first became available on the market was the moment the invention became an innovation. So an innovation is a new or improved product, process or system that has reached the point of first commercial introduction.
Even this moment of achieving innovation is sometimes difficult to pinpoint in a particular case. The first full-scale use of the electric lamp outside of the laboratory was in May 1880 when Edison installed 115 of them on the new steamship Columbia at the suggestion of its owner, Henry Villard, who had become an enthusiast for the electric light after seeing a demonstration at Menlo Park (Figure 13). The electric system was more suitable than open-flame lighting in the confined spaces of a ship. It was so effective that it was 15 years before it was replaced with more modern equipment. However it could be argued that this was not the moment of innovation as there was an element of personal favour rather than it being a purely commercial transaction.
It gave Edison an opportunity to put his light into operation under carefully managed conditions, as well as offering the chance for a public demonstration
One of the first commercial installations of Edison's complete electric light system (generators, distributing circuits and the bulbs) was for the lithography factory of Hinds, Ketcham & Company, New York, in early 1881. Electric lighting allowed the factory to operate at night without difficulty in distinguishing colours.
The first full-scale public demonstration of Edison's urban lighting system was along the Holborn Viaduct in London (Figures 14 and 15). The first generator started up in January 1882 and the Holborn installation was a testing ground for a number of key elements of his more famous installation at Pearl Street Station in New York, which began service later that year.
The Holborn Viaduct project was intended as a temporary demonstration, not a permanent commercial station. By choosing the viaduct, Edison's London agents were able to install the system quickly and with minimal cost because the electrical conduits could be hung underneath without excavations or the need for permits. The viaduct was a testing ground for several key elements of Edison's system.