Microsoft San José Data Center 04

Does the disclosed design cool the whole campus this record covers without evaporating water?

NoCompany statement

The July 2025 design comes from the applicant, the company asking for the exemption. It calls for indirect evaporative cooling. This kind of cooling removes heat by letting water evaporate. The design uses hybrid closed-circuit fluid coolers. These keep the cooling fluid inside closed pipes. In the design, recycled water replaces the water that is lost (the “makeup water”). The design says the coolers can run in dry mode when conditions allow. Dry mode means no water is evaporated.

Source: Microsoft applicant representative / CEC docket, Fourth revised project description, TN 264764, July 14, 2025.

Is a number public for how much water the site or campus needs or consumes?

YesCompany statement

The water supply assessment is dated November 2022. It was filed in the state docket on May 24, 2023. It estimates 690 acre-feet a year of recycled water. One acre-foot covers one acre of land one foot deep. The recycled water is for cooling and for watering land (“irrigation”). The assessment also estimates 1.35 acre-feet a year of drinking water (“potable” water) for domestic demand. These are design estimates. They are not meter readings from a running site.

Source: City water assessment / CEC docket, Final approved water supply assessment, TN 250295, May 24, 2023.

Is clean power accounting for this project public, and does it clearly state the matching period?

Not knownCompany statement

Microsoft’s project description was filed in the state docket on July 14, 2025. It lists a proposed design feature for electricity. Under it, the project owner “shall participate” in San José Clean Energy at the Total Green level. The filing describes that level as “100% carbon-free electricity”. The feature covers the electricity accounts linked to the project. It also allows a contract with San José Clean Energy, or another clean energy program with the same goal. This is the applicant’s own statement. The filing does not say how the clean electricity would be counted. It gives no matching period, such as each hour or each year.

Source: Microsoft applicant representative / CEC docket, Fourth revised project description, TN 264764, July 14, 2025.

Is a final air permit for this project public in the listed records?

Not knownOfficial record

The CEC page describes proposed diesel backup equipment. A state small power plant exemption would not replace the air district’s permit. The air district is the local agency that manages air quality. Microsoft’s July 2025 filing says each engine may run no more than 50 hours a year for testing and maintenance. It says this limit comes from the air district’s permit to build (its “Authority to Construct”) and a California Air Resources Board rule. The filing does not include an Authority to Construct or say that one was issued. The listed records do not include a final air permit. An air permit is the document that sets a site’s air pollution rules.

Sources: California Energy Commission, San José Data Center 04 project record, accessed November 11, 2026; Microsoft applicant representative / CEC docket, Fourth revised project description, TN 264764, July 14, 2025.

Do the listed records show enforceable noise limits, as numbers, for the site when it runs?

Not knownCompany statement

Microsoft’s project filing of July 14, 2025 says the project will follow the city’s standard permit conditions for construction noise. These limit building work to 7:00 AM to 7:00 PM, Monday through Friday. Other hours need a development permit or other planning approval. No weekend building work is allowed within 500 feet of a home. The filing says screen walls about 40 feet above the roof will hide the rooftop equipment. It says the walls will also reduce the equipment’s sound. It gives no noise limit in decibels for the data center once it runs.

Source: Microsoft applicant representative / CEC docket, Fourth revised project description, TN 264764, July 14, 2025.

Do public records show an adopted tariff or agreement that says who pays the project’s power costs?

Not known

The listed records do not answer this.

Does a public record show a local land-use decision?

Not knownOfficial record

The California Energy Commission (CEC) page lists the state exemption case as “Under Review”. It says what happens if the CEC grants the exemption. Local land-use agencies and other agencies then take charge through their own permit processes. The applicant’s filing of July 14, 2025 reports early talks with city public works staff. It says staff expect the city to seek a condition in the project’s use permit (the “Conditional Use Permit”). The listed records include no city decision on that permit.

Sources: California Energy Commission, San José Data Center 04 project record, accessed November 11, 2026; Microsoft applicant representative / CEC docket, Fourth revised project description, TN 264764, July 14, 2025.