The Concord Bridge reported on October 9 that the Concord Municipal Light Plant will add about $6.74 a month to the average household's electric bill for the next five years. That is a real change. A second change is coming in December, and it will be larger during the hours when many households run the dryer, charge the car, and start dinner.
The new charge adds roughly one cent per kilowatt-hour at every hour of the day. The seasonal rate change in December adds almost five cents per kilowatt-hour, but only from 3 to 7 p.m. on weekdays. Both are explained below.
A formula that counted the wrong direction
The Power Cost Adjustment, or PCA, is the line on a Concord Light bill that moves with wholesale power prices. A Light Board memo from September 15 describes it as "an automatic, per-kWh surcharge or credit applied directly to customer electric bills." When wholesale power costs more than base rates assumed, the PCA turns positive. When it costs less, the PCA turns negative and the difference goes back to customers as a credit.
New outside auditors, Goulet, Salvidio & Associates, reviewed the light plant's 2025 financials and found an error that dated to 2021. According to the Bridge, the tracking formula had not accounted for "line loss," the electricity that escapes as it moves through transformers and wires. The old formula showed the light plant owing customers $4.8 million in overcharges. The corrected formula shows the opposite: customers were under-billed by $6.6 million between 2021 and 2025.
That reversal explains why the bill changes in two ways at once. Since 2025, households had been getting a credit through a negative PCA of $0.004 per kWh. For the average household, the Bridge put that credit at $3.70 a month, and it has now ended. CMLP Assistant Director of Power Supply and Energy Management Laura Scott told the Bridge the new auditors "understand that they need to think about [electricity transmission] losses."
The three options the Light Board weighed
Staff gave the Light Board three ways to recover the $6.6 million. Each was priced for an average residential customer using 925 kWh a month:
| Recovery horizon | PCA per kWh | Added monthly cost, 925 kWh household | Collected per year |
|---|---|---|---|
| Three years | $0.01238 | $11.46 | ~$2.2M |
| Four years | $0.00919 | $8.50 | ~$1.6M |
| Five years | $0.00728 | $6.74 | ~$1.3M |
The Bridge reported that Light Board member Warren Leon pushed for the longest option to keep the monthly charge as low as possible, and the board approved the five-year plan on September 23. Member Nicole Grosner asked whether the light plant could fix the formula without charging customers for the past five years. Director Jason Bulger said he did not think the auditors would allow a write-off. The Bridge estimates the total at about $400 over five years for a household with average use.
The total change per kilowatt-hour is larger than $0.00728, because the PCA went from a credit to a charge. It moved from minus 0.4 cents to plus 0.728 cents, a swing of about 1.13 cents per kWh. For a 925 kWh household, that comes to roughly $10.44 a month compared with this summer: the $6.74 surcharge plus the $3.70 credit that no longer applies.
Why October hides most of it
Concord Light's residential Time-of-Day rate, Rate R TOD, took effect April 1, 2026. It splits the year into two seasons, not summer and winter. March, April, October and November are "Shoulder" months. January, February, May through September, and December are "Standard" months.
| Time block | Standard rate per kWh | Shoulder rate per kWh | Seasonal gap |
|---|---|---|---|
| On-peak, weekdays 3 to 7 p.m. | $0.30315 | $0.25379 | about 4.9¢ |
| Off-peak, all other hours | $0.20432 | $0.20230 | about 0.2¢ |
| Super off-peak, daily 1 to 5 a.m. | $0.20117 | $0.19644 | about 0.5¢ |
Every bill also carries a $20 monthly customer charge. The tariff says the per-kWh rates above are then adjusted up or down by the Power Cost Adjustment and the NYPA Power Credit, so they are the starting point for a bill, not the final price.
The surcharge begins in a Shoulder month, when peak power costs almost five cents less per kWh than it will in December. The Bridge reported that the charge appears on October bills. The sources do not say which month of usage an October bill covers. If it reflects late-summer use, the first full Shoulder-season bill with the surcharge may come a cycle later. Either way, the lower Shoulder rates and the new charge overlap for a short time and then separate.
In December, rates return to Standard. Off-peak hours rise by about two-tenths of a cent, which is small next to the 1.13-cent PCA swing. At weekday peak, the seasonal increase is almost 4.9 cents, more than four times the swing caused by the audit correction. For hours outside 3 to 7 p.m. on weekdays, the surcharge is the main change on the bill. During those four hours, the calendar matters more.
The four weekday hours that set the size of the bill
The town's Time-of-Day handout lists the windows this way: peak is 3 to 7 p.m. on weekdays, super off-peak is 1 to 5 a.m. every day, and every other hour is off-peak, weekends included. That makes Saturday and Sunday afternoons off-peak, at about 20 cents per kWh under either season's pricing.
The light plant runs a program for that window. Through Connected Homes, CMLP supports smart thermostats and mini-split controllers, EVs and chargers, water heaters, and residential batteries that cut weekday 3-to-7 p.m. use. The program page lists participation incentives during qualifying supplemental-peak months: $5 per thermostat, $10 per EV or charger, $5 per water heater, and $30 per battery.
The incentives are modest, and the bigger effect comes from the rate itself. Every kilowatt-hour moved out of a December weekday afternoon avoids a price gap of about 10 cents per kWh compared with off-peak hours: $0.30315 against $0.20432. The PCA surcharge applies equally to every hour, so moving usage around does not reduce it. It does reduce how much of the bill is priced at the peak rate.
Opting out has a twelve-month clock
Households can leave Time-of-Day pricing. The town FAQ says customers opt out by completing a form. There is no fee or penalty, and the change takes effect the next billing cycle. There are limits. After a rate change, a customer can switch between Time-of-Day and Opt Out only once in any 12-month period, and must stay on Opt Out for at least 12 months.
The same FAQ says the Opt Out rate runs about 4 percent higher than Time-of-Day for the average customer. The Concord Bridge reported in January that customers could opt out by calling CMLP Customer Service at 978-318-3101, and the FAQ lists the same number for questions. The PCA surcharge applies under either rate schedule, since every residential tariff includes the Power Cost Adjustment Clause. Switching rates changes how a bill is priced. It does not remove the recovery charge.
What the landfill array adds in early 2027
The same week, the Bridge reported on the former town landfill solar site, where the panels that had been there since 2014 have been taken down. The replacement array is about 4.5 megawatts, more than double the site's earlier capacity, with estimated output for nearly 780 homes. Town Manager Kerry Lafleur told the Bridge the new panels should be ready by the end of January 2027.
The project's link to the 3-to-7 p.m. window is its battery. At the Light Board's September 9 meeting, Bulger said the expansion "will feature the first dispatchable battery storage in Concord," with commissioning targeted for early Q1 2027 because of tax deadlines. He also said the removed panels will be reused, not recycled. A battery that can release stored power on demand gives the light plant the same kind of flexibility the Time-of-Day rate asks households to provide. Solar output falls off late on a winter afternoon, around the time the peak window starts.
Other projects are moving more slowly. The Bridge reported that the Concord Middle School rooftop array was still unresolved after an October 7 School Committee discussion ended without a vote, over agreement and roof-warranty concerns. The article also noted that the array at the former W.R. Grace site is due for an overhaul.
For a sense of scale, Bulger told the Light Board on September 9 that newly approved basic service rates bring National Grid's total to about 39.5 cents per kWh, compared with about 21.5 cents for CMLP's average Time-of-Day load shape. That compares rate averages, not actual bills, and household bills will vary with usage. Measured against an average near 21.5 cents, the new 0.728-cent surcharge is small. The 4.9-cent December rise at weekday peak is larger.
If you're preparing a Concord home for market and want to know how utility costs, including the Time-of-Day rate and this five-year recovery charge, might come up in a buyer's questions, Nancy Cole Team can help you get ready for those conversations. Request a confidential market consultation, and we'll go through your home's particulars with you.
This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.