The new electric streetlights may be a brighter white, but they have saved the City some deep green in a hurry.
Just one year into the LED (Light-Emitting Diode) streetlight conversion program, the City of Boston estimates that it saved $4.7 million in 2014 with just 71 percent of the City retrofitted. Also, through rebates and savings, the initial $15 million payout for the program has nearly been completely paid for.
LED lighting began to replace the traditional mercury vapor lighting in 2014 after a pilot program in neighborhoods outside of Charlestown was deemed successful in 2013. LEDs are simple semi-conductor devices that emit a cool, bright white light when an electrical current passes though. The trick, however, is that they use minuscule amounts of electricity and do not produce any heat – such as with the mercury vapor lights or traditional light bulbs – so they last much longer as well. On the flip side, the initial payout is quite expensive, and the retrofit kits that are being placed upon existing poles throughout the City do cost a pretty penny.
City officials, however, said that much more in savings will be reaped over the coming years than will be spent in the retrofit program.
There are approximately 64,000 electric streetlights throughout Boston and 45,191 have been replaced with LED kits – which is 70.6 percent. In Charlestown, there are 1,804 electric streetlights and 1,339 have been converted, or about 73 percent in the neighborhood so far.
The work is ongoing in Charlestown and citywide, officials said.
Moving on to the bottom line, City officials estimated that the new LED lights put in place in 2014 saved 32.42 million kilowatt-hours (kWh). An average home in Massachusetts uses about 7,000 kWh, so the streetlight savings last year, in terms of electricity use, would power about 4,630 single-family homes for a year.
In dollars and cents, based on the average rate paid in 2014 for electricity by the City of Boston ($0.145 per kWh), the 32.42 million kWh saved would translate to $4.7 million saved in electricity costs for streetlights throughout Boston in 2014.
To acquire the LED kits, the City had spent $15 million on the program by September 2014, but due to grants from the utility company for implementing more efficient lighting, Boston also received $8.444 million in utility rebates – a program largely funded by the federal government. That’s more than half the cost of the entire program, and when adding in the 2014 savings of $4.7 million, the entire program has nearly been paid for within the first year of operation.
City officials also pointed out that the return on that investment will only grow with the savings each year, as the LED light kits are guaranteed to last 15 years each – far longer than their mercury vapor predecessors.
Naturally, in Charlestown, all things related to lighting and streetscapes are a little more difficult to define than the typical Boston neighborhood.
And the hitch in the City’s most historic neighborhood are gas-powered lamps.
There are many gas-powered historic streetlights in Charlestown that fall outside the program – as they don’t rely on electricity and cannot be converted to LED without losing their historic character.
City officials said Charlestown has 1,105 gas lamps (about one-third of the total streetlights), but there are some savings to be reaped from them and the City does have a program currently being implemented to retrofit all of the gas lamps with solar-powered electronic starting burners.
Some 550 of Charlestown’s gas lights – about 50 percent – have been converted to solar-powered starting devices.
As for the LED conversions throughout Boston, the City does expect to finish the program by the end of calendar year 2015.
The program is being implemented by the City’s Department of Public Works.