NSTAR Electric Company d/b/a Eversource Energy, Rate R-1HP (M.D.P.U. No. 85), priced in M.D.P.U. No. 1-26-E 'Summary of Electric Service Delivery Rates', Part A, effective 07-01-26
Effective
2026-07-01
Structure
time-of-use
· 2 rate periods
Covers
delivery only — delivery alone. Supply is set by market price with no filed figure, so a real bill is higher. NOT comparable to a bundled rate
Transcription notes recorded when this tariff was encoded, including anything deliberately left out.
NSTAR Electric Company d/b/a Eversource Energy, Massachusetts. A SEPARATE operating company from The Connecticut Light and Power Company, which is also Eversource and files an entirely different tariff: CL&P puts delivery and supply on one sheet, NSTAR files delivery only.
Rates are built from the components filed in M.D.P.U. No. 1-26-E, 'Summary of Electric Service Delivery Rates', Part A, and each is asserted at build time against the Total Delivery column the tariff prints on the same row. The published total is a check, never the source.
M.D.P.U. No. 1 is the authority, NOT the customer-facing 'Summary of Electric Rates' PDFs published per service area. The filed R-1HP schedule (M.D.P.U. No. 85) carries no numbers at all - every line reads 'As per M.D.P.U. No. 1 as in effect from time to time' - which is what identifies No. 1 as the source.
TRAP in the customer-facing summary: it lists 'Energy Efficiency Charge $0.02292' as one of eleven components. In M.D.P.U. No. 1 that figure is a SUBTOTAL of System Benefits $0.00250 and the Energy Efficiency Reconciling Factor $0.02042, printed beside the two columns that actually add. The additive components are used here.
TWO RATE SETS, not four service areas. M.D.P.U. No. 1 groups them BOST/CAMB/SOUTH/WMA and CAPE. Greater Boston, Cambridge, South Shore and Western Massachusetts are identical on every component; Cape Cod & Martha's Vineyard differs in exactly one, the energy efficiency reconciling factor, by $0.01446/kWh. Service areas map to rate sets in data/current/nstar_service_areas.json.
Western Massachusetts - the former WMECO territory - shares the mainland rates. The customer-facing summary pages offer only the four Eastern Massachusetts areas and would have left WMA out silently.
Revenue Decoupling is the one component that varies BETWEEN schedules: R-1 $0.00539, R-3 $0.00527, R-1HP $0.00443. Copying a component list between schedules produces a rate that is wrong and still looks plausible.
EXCLUDED: Massachusetts state and local taxes.
Rate set 'cape', which is the filed grouping for: Cape Cod & Martha's Vineyard.
SEASONAL, unlike R-1 and R-3. M.D.P.U. No. 1 labels the rows 'Energy (kWh) - Summer' and 'Energy (kWh) - Winter', which is what fixes the pairing: SUMMER is the expensive block ($0.19717) and WINTER the discounted one ($0.11985, 61% of summer). The customer-facing summary prints the two blocks with their season labels rendered as column headers away from the data, where the pairing is not recoverable.
MONTH BOUNDARIES ARE NOT IN A FILED TARIFF. M.D.P.U. No. 1 names the seasons without stating their months; No. 85 does not mention seasons at all; No. 3 defines no residential season. May-October and November-April come from Eversource's customer-facing summary, which is the utility's own published statement but is not a filed document. Encoded on that basis, and recorded here rather than presented as filed.
Available only to customers who qualify for R-1 and who affirm ownership of an installed heat pump. /compare cannot check that.
DELIVERY ONLY. This tariff prices what NSTAR charges to deliver electricity and excludes the cost of the electricity itself. A Massachusetts customer also pays either Basic Service or a competitive supplier. Use the matching bundled tariff for a whole bill; use this one to compare NSTAR schedules against each other, which is valid because supply is identical across all of them.
NOT ENCODED: R-2 (M.D.P.U. No. 8), R-2HP (No. 86) and R-4 (No. 10), the income-qualified assistance versions of R-1, R-1HP and R-3. They are filed in the same table and readable the same way, but this encoding cannot express eligibility, so /compare would recommend them to people who cannot have them. They belong in the CARE-style discount machinery in rategrid/care.py rather than as separate tariffs.
Think a figure here is wrong?
Email support@rategrid.dev
with this plan's name and what the filed sheet says. Every rate on this page was
transcribed from the document linked above, so a report that quotes the sheet can
be checked against it and corrected.
Change history
The source document is fetched daily and every version is kept.
Utilities do not publish superseded rates, so this record does not exist
elsewhere once a rate changes.
No changes detected since monitoring began. The source sheet is checked daily.