Utility data · NM, TX · Investor Owned

Southwestern Public Service Co

322,686 residential customers. A household here uses 11,633 kWh a year and pays about $1,502 for it. A standard rooftop array at this latitude would offset $1,502 of that bill.

Every figure on this page is marked with the source that produced it; the marks resolve in Sources.

What the numbers say

An array here covers the whole household load

The modelled array out-produces what a household in this territory consumes, even in a weak production year. Savings are capped by the bill rather than by the roof, which is why no range is shown.

Modelled annual offset$1,502Capped by the bill: the array out-produces the household · source 2

Residential rate12.9¢−23.7% against the 16.9¢ national mean · source 1

Household use11,633 kWhAverage across this utility’s residential customers · source 1

Your own numbersOpen the calculatorThis page is a territory average, not a quote

What is particular to this territory

Investor Owned, serving 322,686 residential accounts.
A household here uses about 969 kWh a month and pays $125 for it, at 12.9¢.
That rate is 24% below the 16.9¢ national customer-weighted mean.
Households here use 15% more than the 10,121 kWh national average.
The annual bill of $1,502 is 4% below the $1,568 national average, or $66 a year less.
Modelled output varies by about 3.1% year to year, from the PVGIS-NSRDB radiation record.
The reference array is modelled at 13,288 kWh here, worth $125 a month against this rate.
The modelled array covers 114% of that use, out-producing the household by 1,655 kWh in a typical year, so the offset is capped by the bill.

The figures behind that

Customers, use, rate, and bill are filed with the EIA or computed from filed figures. Array output is modelled by PVGIS, and the offset and ranks combine the two. Every row names the source it rests on and the date of the event that source describes. Nothing here is a quote or an offer.
Measure	Value	How it is derived	Source
Residential customers	322,686	EIA-861, filed	1
Average annual use per household	11,633 kWh	Residential sales ÷ customers	1
Residential rate	12.9¢	Residential revenue ÷ sales	1
Average annual bill	$1,502	Use × rate	1
Modelled array output	13,288 kWh ± 418 kWh	8 kWp at 20°, south facing	2
Modelled annual offset	$1,502	Rate × lesser of use and output	2

Month by month

The series starts in August 2026. One row is not a trend, and this page will not claim one until there are enough rows to show a direction.

Appended once per source event, bound to solar-savings-history-v1. Each row carries the date of the event its figures describe.
Month	Rate	Annual bill	Modelled offset	Source event as of
August 2026	12.9¢	$1,502	$1,502	2026-08-20

What the EIA publishes about this utility

Beyond sales and revenue, EIA-861 collects separate files that not every utility appears in. For Southwestern Public Service Co our ledger records usable interruption metrics, an entry in the net metering file, and a declared service territory. Those files are not summarised on this page; this states only whether the agency has data to summarise.

The interruption side of that data does have a page. How long the power stays off is covered for New Mexico and Texas, an ordinary year against a year with major storms — the half of the decision an array cannot answer, because a grid-tied system shuts down during an outage.

Other utilities in NM, TX

Denton County Elec Coop, Inc — 13.8¢, offsets $1,621–$1,736 a year
Pedernales Electric Coop, Inc — 12.2¢, offsets $1,438–$1,540 a year
El Paso Electric Co — 12.7¢, offsets $1,089 a year
Entergy Texas Inc. — 13.7¢, offsets $1,608–$1,722 a year
Southwestern Electric Power Co — 12.6¢, offsets $1,427–$1,523 a year
Public Service Co of NM — 15.6¢, offsets $1,073 a year

Sources

Each figure above carries a mark. These are what the marks mean, with the date of the event each source describes rather than the day this page was built.

Source 1 — U.S. Energy Information Administration: EIA-861 2024 final release, bulk XLSX (f8612024.zip)
Source 2 — European Commission Joint Research Centre: PVGIS v5.2 PVcalc, European Commission Joint Research Centre
Source 3 — GeoStellar: GeoStellar utility-page-priority-v2 priority evidence

When this data is from

Customers, sales, and revenue are EIA-861 2024 final release, bulk XLSX (f8612024.zip), data year 2024, published here as GS-SOURCE-EIA861-RESIDENTIAL-2024 with source event 2024-12-31. Modelled array output is PVGIS v5.2 PVcalc, European Commission Joint Research Centre, retrieved 2026-08-20 from PVGIS-ERA5 and PVGIS-NSRDB, published as GS-SOURCE-PVGIS-PVCALC-V5-2. Which territories the index covers comes from GS-SOURCE-GEOSTELLAR-UTILITY-PAGE-PRIORITY-V2, source event 2026-08-19; the comparisons on this page are taken against every utility the EIA reports with residential detail, not against the subset that has a page. The dates differ because the filings are annual and the production model is not. The monthly series on this page begins in August 2026.

What this page is not

It is a territory average, not an estimate for your house. The rate is a full-year average across every residential customer this utility serves, not a tariff and not the rate on your bill. The array is a standard one modelled at your state’s population centre, not your roof. Net metering terms, installation cost, incentives, and financing are not modelled at all. The methodology page states the formula and the limits we know of.

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