Holyoke Water Power generated most of the electricity in the city pre-1902. See the chart below for use in lights. Thus in this tiny comparison, there is a very obvious shift from gas over to electric. The age of electricity was upon us.
| lights | electric lights | gas lights | naphtha lights (oil) | |
| 1875 | 85 | 0 | 60 | 25 |
| 1876 | 101 | 0 | 67 | 34 |
| 1878 | 113 | 0 | 78 | 35 |
| 1879 | 125 | 0 | 85 | 38 |
| 1880 | 136 | 0 | 99 | 37 |
| 1882-1883 | 163 | 44 | ||
| 1890 | 309 | 159 | 88 | 50 |
| 1891 | 333 | 183 | 49 | 39 |
Holyoke Gas and Electric was created in 1902 as a public city department from the electrical division of the private Holyoke Water Power Company.
In 1952 HWP starts Springdale Industrial Park.
Also in that year the Mount Tom Power Plant is started at 136 MW. That gives Holyoke a total of 207 MW.
Riverside Station makes 44 MW from a high pressure steam station. The power is piped to mills on lower Appleton Street.
A Jet Gas Turbine was purchased in December of 1963 and dedicated October 14 1964.
A 6,250 KVa number 9 generator was installed in 1941.
At 5:16 PM of November 9 1965 the Northeast Blackout hit the USA. This was the largest electrical blackout in American history.
In 1967, a new 13 kV aerial cable and 2000 KVA transformer are installed at the Mt Tom Ski area. In that same year on Dec 15th a Holyoke Substation was put in place.
There were other companies in Holyoke that made energy. Look at the coal plant in northern Holyoke.
