Data center emissions compliance

Keep Data Center Start-ups On Track With Onterris

Data centers require dozens or even hundreds of engines and turbines to be permitted, commissioned and tested on aggressive timelines. Onterris combines air permitting, stack testing and ongoing emissions support through one coordinated team, helping owners, developers and operators bring data centers online quickly, maintain compliance and operate efficiently throughout their lifecycle.

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Align testing and permitting

Align permit assumptions, test methods and monitoring obligations before they become commissioning constraints.

Protect startup timelines

Coordinate test methods, crews, equipment, load conditions and reporting across complex projects so emissions testing does not become a critical path delay.

Make faster commissioning decisions

Avoid the “test-wait-retest” loop by using onsite FTIR emissions data to verify equipment, tune controls and resolve performance issues during the same deployment.

Maintain compliance after go-live

Execute recurring source testing, CEMS/PEMS audits, permit reporting and control-system verification as one connected program rather than a series of disconnected projects.

Comprehensive emissions support for data centers

Rapid deployment of backup generators and on-site turbines creates a complex, site-wide compliance footprint and a need to coordinate permitting, commissioning, monitoring and reporting. Onterris connects planning and permitting through commissioning and recurring compliance testing so teams can protect go-live timelines and operate with confidence.

Air permitting and test planning

Onterris helps data center teams define air permitting and testing requirements before equipment is installed, so proposed limits, monitoring obligations and field methods can be demonstrated efficiently once equipment is installed.

Air permit applications and modifications
PSD, NSR and nonattainment permitting support
BACT and LAER evaluations
Air dispersion modeling and air quality impact analysis
Emission inventories, potential-to-emit calculations and site-specific emissions factor strategy
Permit-condition and applicability review
Test protocol development, agency coordination and documentation

Engine and turbine commissioning and control-system verification

Onterris has a nationwide footprint of source testing specialists to perform independent emissions testing during startup, acceptance and turnover to verify that power assets meet performance requirements and evaluate whether emissions-control systems are properly tuned.

Initial compliance demonstrations
OEM emissions-guarantee verification
Reciprocating engine and combustion turbine testing
Testing at required load points
NOx, CO, VOC, particulate matter and formaldehyde measurement
SCR and SNCR optimization
Ammonia-slip measurement and injection balancing
Oxidation catalyst inlet and outlet testing
Real-time FTIR measurement for tuning and troubleshooting

CEMS, PEMS and temporary emissions monitoring

Our specialists commission emissions monitoring systems when required and can deploy temporary CEMS to maintain compliance and operations during shut-down, malfunction or maintenance.

Temporary CEMS deployment
Continuous monitoring during defined commissioning windows
PEMS model-development data
Seven-day calibration drift testing
Relative accuracy test audits (RATA) and performance specification tests (PST)
Cylinder gas audits
Site-specific QA/QC documentation
CEMS training and reporting support

Ongoing compliance testing

Once data centers are operational, our team helps teams meet recurring source-testing requirements and confirm that engines, turbines and emissions-control systems continue to operate within permitted limits.

Initial and recurring permit testing
NOx,CO and both filterable and condensable particulate matter testing
VOC and total hydrocarbon testing
Methane and ethane correction for true VOC reporting
Ammonia-slip testing and formaldehyde verification
Compression-ignition engine testing
Load-bank testing
SCR, DOC and DPF performance evaluation
Data validation, final reporting and regulatory submittal support

Advanced emissions and emission-factor testing

When conservative default factors, low emission levels or complex exhaust conditions limit permitting or dispersion modeling, Onterris applies specialized methods, including low level particulate testing and FTIR, to develop more representative source-specific data.

Low-level particulate matter measurement
EPA OTM-37 dilution-tunnel sampling
EPA Part 1065 particulate testing
PM2.5 and PM10 testing
Testing of SCR-equipped engines and turbines

Specialized FTIR spectroscopy testing

Trained FTIR specialists provide the laboratory-grade precision required to navigate strict emission limits, ensuring your data center remains compliant without sacrificing operational performance.

EPA Method 320 for ‘Gold Standard’ accuracy and applicable ASTM testing
Real-time measurement of NOx, CO, ammonia and formaldehyde
Multi-pollutant analysis from one sampling location
Low-level formaldehyde measurement
SCR tuning and ammonia-slip evaluation
Oxidation-catalyst performance verification
Testing for complex or high-moisture exhaust streams
Pretest emissions characterization

Confident emissions compliance, every step of the way

Every data center, while unique in its requirements, moves through a similar lifecycle. Onterris provides the national scale and technical expertise to manage the full testing lifecycle, ensuring your facilities remain compliant while optimizing site performance.

Phase 1: Planning and permitting

Define emissions assumptions, evaluate regulatory pathways, model impacts and establish testing and monitoring requirements.

Typical support:

Permit applications
BACT and LAER evaluation
Dispersion modeling
Source and fleet inventories
Testability review
Testing and protocol strategy

Phase 2: Commission and verify

Verify manufacturer guarantees, demonstrate initial compliance and use real-time data to tune equipment and controls.

Typical support:

Acceptance testing
Initial compliance testing
SCR optimization
Catalyst verification
FTIR measurement
Low-level PM testing

Phase 3: Certify and audit

Support CEMS and PEMS development, certification and recurring audits using independent reference measurements.

Typical support:

Temporary CEMS
PEMS model data
Performance specification tests
Relative accuracy test audits
Cylinder gas audits
QA documentation

Phase 4: Maintain compliance

Execute recurring testing, evaluate control-system performance and adapt the compliance program as conditions change.

Typical support:

Periodic source testing
Emission-factor updates
Regulatory reporting
Catalyst performance trending
Permit modifications
Community engagement

The most trusted team in data center emissions compliance

Shagun Bhat, PhD

Managing Principal, Air Quality Consulting

Dr. Shagun Bhat brings nearly 20 years of air quality consulting expertise to a variety of industries. A chemical engineer by trade, his areas of expertise include New Source Review (NSR) and Prevention of Significant Deterioration (PSD) permitting, air dispersion modeling, emissions inventory development, use of optical technologies for emission inventory improvement, and litigation support.

Blake Ericson

Business Manager, Stack Testing

Blake has over a decade of experience in air quality management, engineering and regulatory testing, with a primary focus on power start-up and commissioning stack testing, as well as Fourier transform infrared (FTIR) technologies. He also brings a strong background in financial forecasting, client growth strategy and performance analysis to support business expansion and customer retention.

Greg Burch

Regional Vice President, Stack Testing

Greg Burch brings more than 30 years of industry experience to the Onterris team where he currently works as Regional Vice President of the Gulf Coast region with deep expertise in refining, power generation and data center projects. He is also a a Qualified Stack Test Individual (QSTI) Groups I, II, III and IV.

Talk to an expert about your data center emissions compliance

Build an emissions compliance program you can operate with confidence, with one partner coordinating air permitting, stack testing and ongoing regulatory support. Fill out this quick form to schedule time with an air quality expert.

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