Data centers vs Arizona's power and water: what the numbers show

Arizona data center power use is documented. Arizona data center water use is not. That asymmetry is the single most important thing to understand about this debate, because it means one half of the argument is fought with tariff filings and the other half with estimates from advocacy groups and consultancies.

This article separates what is measured from what is projected, and labels every figure with where it came from.

The short version

The scale of the buildout, with the right numbers

A widely repeated claim holds that metro Phoenix hosts about 707 MW of data-center capacity, more than any US metro except Dallas, across roughly 140 facilities. That claim is stale and the ranking is wrong.

The 707 MW figure comes from JLL’s US Data Center Report for the first half of 2024. The “roughly 140 facilities” count comes from a separate AZ Family report in July 2025 that contains no capacity figure at all. The two were welded together somewhere along the way.

JLL’s midyear 2025 report (opens in a new tab), using H1 2025 data, puts metro Phoenix at 904 MW of inventory with 3 percent vacancy (about 31 MW available), 1,307 MW under construction and roughly 4,154 MW planned.

View the numbers as a table

Operating data-center inventory by North American market, MW — full dataset

Market	Value ( MW)
N. Virginia	5574 MW
Dallas	1539 MW
Atlanta	1072 MW
Pacific NW	1045 MW
Austin/SA	921 MW
Phoenix	904 MW
Chicago	882 MW

Source: JLL North America Data Center Report, midyear 2025 (H1 2025 data).

On existing inventory, Phoenix sits behind Northern Virginia, Dallas-Fort Worth, Atlanta, the Pacific Northwest and Austin-San Antonio. Northern Virginia alone is more than six times larger.

The pipeline is where Phoenix genuinely ranks second. JLL puts Northern Virginia’s pipeline near 7 GW and both Phoenix and Dallas near 5 GW. CBRE, which counts colocation only and therefore produces smaller numbers, put Phoenix at 602.8 MW at year-end 2024 with 1.9 percent vacancy and ranked it fourth in North America on that narrower basis.

This means the story is about what is coming, not what is here. The operating fleet is mid-sized. The queue is enormous, and the queue is what forces utilities to build.

How much power is actually committed

The most reliable Arizona figures are not market reports. They are sworn testimony.

In direct testimony filed in the pending APS rate case (opens in a new tab), Docket E-01345A-25-0105, APS witness Jessica Hobbick stated:

• APS is contractually committed to approximately 3,296 MW of data-center load, comprising 1,215 MW from existing facilities and 2,081 MW expected online by the end of 2028.
• APS is engaged with prospects representing a further 16,908 MW of potential load, a figure that “surpasses Arizona’s current system peak demand of roughly 8,200 MW.”

APS publishes the same picture as an uncommitted queue of 19.0 GW against a 2025 peak of 8.7 GW and a 2035 forecast of 12.0 GW. On its own numbers, data centers were about 5 percent of the 2025 peak.

SRP’s side, from figures put on the record at the Arizona Corporation Commission’s April 2026 large-load workshop: 59 large-load customers totalling roughly 7,000 MW, with data centers estimated at 441 MW of the 2025 peak, or about 5.1 percent. Statewide, the workshop recorded 2,000-plus MW operating with 10,600-plus MW planned.

Both utilities land near the same share today. Both face a queue several times larger than their entire current system.

The national picture

Arizona is not unusual, it is early. The best national accounting is Lawrence Berkeley National Laboratory’s 2024 United States Data Center Energy Usage Report (opens in a new tab), LBNL-2001637, published December 2024.

View the numbers as a table

US data-center electricity consumption, TWh — full dataset

Period	US data-center consumption ( TWh)
2014	60 TWh
2018	76 TWh
2023	176 TWh
2028 (proj.)	452 TWh

Source: Shehabi et al., 2024 United States Data Center Energy Usage Report, LBNL-2001637, December 2024. 2028 shown as the midpoint of a 325 to 580 TWh range.

The report’s stated figures: consumption held at about 60 TWh through 2014 to 2016, reached about 76 TWh in 2018 (1.9 percent of US electricity), and 176 TWh by 2023, representing 4.4 percent of total US electricity consumption. Its 2028 projection is a range of roughly 325 to 580 TWh, or 6.7 to 12.0 percent of forecast national consumption. Assuming 50 percent capacity utilization, LBNL translates that into a total power demand of 74 to 132 GW.

The width of that range is itself informative. A projection that spans nearly a factor of two four years out is a projection nobody should be treating as a plan.

EIA’s own framing, from a January 13, 2026 press release (opens in a new tab), is that US electricity use will grow 1 percent in 2026 and 3 percent in 2027, “the first time since 2007 that power demand has risen for four years in a row,” attributed to “increasing demand from large computing facilities, including data centers.” EIA does not publish a standalone data-center consumption series comparable to LBNL’s.

How much water do Arizona data centers use?

There is no authoritative figure. The Arizona Department of Water Resources does not report data centers as a water use category, and no state filing requires facilities to disclose consumption.

This is not a case of the number being contested. It is a case of the number not existing. ADWR reports by Active Management Area and by Community Water System, classifying use as municipal, industrial or agricultural. Data centers fall inside “industrial” alongside everything else and are not broken out.

What does exist, ranked by how much weight it can carry:

The ASU figure is the most useful because it comes with context. The same document puts golf courses at 300 to 1,200 acre-feet per year and non-nuclear power plants at 800 to 10,000 acre-feet per year. One acre-foot is 325,851 gallons.

Put plainly: a large data center’s cooling draw is in the same band as a golf course and well below a thermal power plant. That is a materially different picture from the one implied by the more dramatic headlines, and it is also a range rather than a fact.

What Arizona cities are doing about it

Municipalities have acted where the state has not, but the ordinances cap and condition use rather than measure it. From the ASU review, nine water providers plus EPCOR, covering more than 4 million Arizonans, have large-volume water user measures:

Marana’s is the strictest: no water service “for the purposes of cooling, humidity control or similar operations” for a data center.

There is a structural gap underneath all of this. Under A.R.S. 45-515, a developer refused municipal service can obtain a general industrial use groundwater permit, valid up to 50 years, and pump directly. The fees are roughly $2.12 per acre-foot for water quality assurance plus $2.00 to $3.50 per acre-foot in withdrawal fees, against municipal industrial rates of roughly $700 to $2,200 per acre-foot. Those withdrawals are not subject to replenishment obligations.

A city saying no does not necessarily stop the facility. It changes where the water comes from and who accounts for it.

Why Arizona, and why the tension

Arizona drew the industry with cheap land, low natural-disaster risk, tax incentives, established fiber routes and electricity that used to be inexpensive. Those advantages are now in tension with the strain the facilities place on the grid and on water supply.

CBRE’s H2 2025 Phoenix market chapter notes that “SRP and APS power-delivery restrictions are limiting the availability of powered land sites.” The constraint has shifted from land to interconnection.

The state is working through it in public. The ACC opened Docket No. E-00000A-25-0069 into rate classifications and data centers, and held a large-load workshop on April 16, 2026 covering statewide standard-service mechanisms, large-load tariffs, integrated resource plan modifications and hook-up fees. No rule came out of it. A further workshop was named as a next step.

What it means for homeowners

The connection to a residential bill is indirect but traceable. The buildout drives load growth. Load growth drives generation and transmission investment. That investment is recovered through rate cases. Rate cases set what households pay.

Whether large loads carry their full share of those costs is the live fight, covered in are data centers raising Arizona electric bills. The bill mechanics on the other end are in why your Arizona electric bill keeps going up, and the pending APS case is tracked on the APS rate increase page.

None of this is something a single household changes. What a household does control is how many kilowatt-hours it buys from a grid under this much pressure, and when it buys them, which is the calculation is solar worth it in Arizona works through in detail.

Common questions

How much power do Arizona data centers use?

Metro Phoenix has about 904 MW of operating data-center capacity as of JLL’s midyear 2025 report, with 1,307 MW under construction. On the utility side, APS reports being contractually committed to roughly 3,296 MW of data-center load, with data centers making up about 5 percent of its 2025 system peak.

The forward numbers are much larger. APS has disclosed engagement with prospects representing 16,908 MW of additional potential load, which exceeds Arizona’s entire current system peak of roughly 8,200 MW.

Is Phoenix the second-largest data center market in the US?

No, not on operating inventory. JLL’s midyear 2025 figures put Phoenix at roughly 904 MW, behind Northern Virginia (5,574 MW), Dallas-Fort Worth (1,539 MW), Atlanta, the Pacific Northwest and Austin-San Antonio.

Phoenix does rank second nationally on the forward pipeline, at roughly 5 GW planned against Northern Virginia’s 7 GW. The “second only to Dallas” claim traces to an older JLL H1 2024 figure of 707 MW and no longer holds.

Do data centers use a lot of water in Arizona?

Nobody can answer that precisely, because Arizona does not collect the data. The Department of Water Resources reports water use by municipal, industrial and agricultural category, and data centers are not broken out.

The best available estimate is from ASU’s Kyl Center for Water Policy: evaporative cooling at a data center can range from 250 acre-feet per year to well over 2,000, depending on facility size. For comparison, the same source puts golf courses at 300 to 1,200 acre-feet per year and non-nuclear power plants at 800 to 10,000.

Why is Arizona attractive to data centers?

Cheap land, low natural-disaster risk, tax incentives, established fiber networks and electricity that used to be inexpensive. Arizona also offers something increasingly rare: large contiguous parcels near existing transmission.

Those same advantages are now in tension with grid and water constraints. CBRE notes that SRP and APS power-delivery restrictions are limiting the availability of powered land sites, which means the binding constraint has moved from real estate to interconnection.

What does any of this mean for me as a homeowner?

Indirectly, quite a lot. The buildout drives demand growth, demand growth drives grid investment, and grid investment flows into rate cases that set residential rates. APS has requested a 16.44 percent residential increase in a case due for a Commission vote by December 31, 2026.

Whether data centers are paying their proportionate share of that investment is disputed and unresolved. Either way the investment is happening and the bills keep arriving on their own schedule.

Related reading

• Are data centers raising Arizona electric bills? lays out the cost-allocation dispute and both sides’ filings.
• Why your Arizona electric bill keeps going up breaks a residential bill into base rates and adjustors.
• The APS rate increase page tracks the pending rate case.
• Arizona grid peak demand explained shows the hourly load shape all this capacity is being built to serve.
• Is solar worth it in Arizona? covers the household-level response to rising grid pressure.

Capacity, consumption and water figures were verified against JLL, LBNL, ACC, APS and ASU sources on August 10, 2026. This is a fast-moving topic and every figure above carries a different vintage, so check the linked sources before relying on any of them.

• Rate Cases
• Arizona