---
title: 'Senior Test Engineer - HIL at ON.energy'
canonical: 'https://feeny.ai/job/senior-test-engineer-hil-on-energy-houston-texas-tafgqv02q4w6'
type: 'job'
last_seen: '2026-09-14'
---

# Senior Test Engineer - HIL at ON.energy

- **Company:** ON.energy
- **Location:** Houston Texas, United States
- **Posted:** 2026-09-11
- **Last confirmed live:** 2026-09-14
- **Apply:** https://job-boards.greenhouse.io/onenergy/jobs/4401939009

## Job description

ON.energy is building the backbone of energy and AI infrastructure powering grid-safe data centers and mission-critical facilities. The company supplies and operates hyperscale power systems that solve the toughest resilience challenges, delivering custom solutions for AI data centers, mission-critical facilities, and front-of-the-meter assets. ON recently announced a 5GW partnership, with 3GW currently under construction across multiple hyperscale data center campuses. With patented technology and proprietary software, ON.energy develops projects worldwide that set new benchmarks for resilience.

## Role Summary

The HIL Test Engineer develops and operates hardware-in-the-loop and real-time simulation capability for ON.energy storage and power conversion products. The role covers real-time model development, integration of controllers and firmware with the simulation environment, execution of structured test campaigns, and the reporting that supports design reviews and product release. This is a hands-on laboratory and integration role, working closely with the controls, firmware, modeling, and product engineering teams.

## Key Responsibilities

- Develop and maintain real-time models of plant, grid, and equipment behavior for use in controller testing.
- Configure and operate the HIL environment, including real-time simulator, I/O interfaces, signal conditioning, and data acquisition.
- Integrate product controllers, control software, and firmware builds with the simulation environment, and maintain those configurations under version control.
- Integrate supplier-provided equipment models and develop equivalent models where required.
- Plan and execute functional, performance, fault, boundary-condition, and regression test campaigns against defined acceptance criteria.
- Verify control performance across normal operation, disturbances, abnormal conditions, and recovery.
- Compare test results against offline simulation studies and laboratory measurements, and resolve discrepancies.
- Develop scripts and tooling to automate test execution, data processing, and reporting.
- Investigate failures with controls and firmware engineers, support root-cause analysis, and re-test to closure.
- Prepare test reports documenting method, configuration, results, limitations, and recommendations.
- Maintain laboratory safety, equipment, configuration records, and documentation.

## Key Requirements

- Four or more years in HIL testing, real-time simulation, controls validation, or laboratory testing of grid-connected power electronics.
- Bachelor's degree or higher in electrical engineering, power systems, controls engineering, or a related discipline.
- Direct experience on at least one real-time simulation platform, such as RTDS/RSCAD, Typhoon HIL, or OPAL-RT.
- Working capability with offline simulation tools such as MATLAB/Simulink and PSCAD, and an understanding of what has to change when a model is made to run in real time.
- Grounding in inverter controls, energy storage systems, and power system dynamics.
- Python, or a comparable language, used in earnest for test automation and data analysis.
- Test plans, procedures, and acceptance criteria you have authored yourself, and the analytical rigor to stand behind the results.
- Familiarity with SCADA systems and industrial communication protocols such as Modbus, DNP3, CAN, and IEC 61850.
- Comfort on the bench with power supplies, oscilloscopes, transducers, and data acquisition hardware.
- The ability to present technical findings credibly to engineering audiences and clearly to field and commissioning personnel.

## Preferred Experience

- Experience with grid-forming and grid-following inverter control.
- Experience with uninterruptible power supply systems, microgrids, or facilities serving critical load.
- Familiarity with ISO or utility interconnection requirements, model quality testing, or third-party product certification.
- Continuous-integration pipelines driving automated test suites, with version control applied to models as rigorously as to code.
- Prior collaboration with national laboratories or university test centers.

For US-based roles - What you’ll get:

- Competitive salary + annual performance-based bonus eligibility
- Medical, dental, and vision insurance
- 401(k) with company match
- Paid time off and company holidays

For Mexico-based roles - What you’ll get:

- Competitive salary + annual performance bonus eligibility
- Christmas Bonus (Aguinaldo): 30 days
- Major medical expenses and life insurance
- Paid time off and holidays (per local policy)

For all roles:

- Professional development and growth opportunities
- Opportunity to grow with a mission-driven team shaping the future of clean energy
- Equal Opportunity: ON.energy is committed to equal employment opportunity and to maintaining a work environment free of harassment, discrimination, or retaliation.
- Accommodations: If you need an accommodation during the application process, email recruitment@onenergystorage.com
- Benefits vary by role and location and are subject to change.

Agency Notice: ON.energy does not accept unsolicited resumes from staffing agencies, search firms, or third-party recruiters. Resumes submitted without a fully executed Master Services Agreement (MSA) and a written request from an authorized member of our Talent Acquisition team will be considered the property of ON.energy. No placement fees or compensation will be paid for unsolicited candidate submissions.

## About ON.energy

## Company Overview
- **One-liner**: ON.energy supplies and operates hyperscale power systems built to meet the world’s most demanding resilience challenges, delivering grid-safe energy and AI infrastructure through patented technology and proprietary software.
- **Entity Type**: Private (Series B, multiple debt financing rounds)
- **Headquarters**: Miami, Florida, United States
- **Founded**: 2016
- **Founders**: Alan Cooper (CEO & Co-Founder) and Ricardo De Azevedo (CTO & Co-Founder)

## Core Business
- **Primary Industry**: Energy Technology (energy storage, battery systems, critical power infrastructure)
- **Target Customers**: AI data centers, mission-critical facilities, grid-scale asset owners (B2B, enterprise, infrastructure)
- **Mission/Purpose**: To build the backbone of energy and AI infrastructure, making energy resilient, clean, abundant and affordable while solving the toughest power problems in the world.

## Products & Services
- **Hyperscale Power Systems**: Custom, end-to-end solutions for AI data centers and mission-critical facilities, combining advanced power electronics, battery storage and proprietary control software.
- **ON.command™ Energy Management System**: Proprietary software platform for managing gigawatt-scale deployments, optimizing grid stability, energy arbitrage, and uptime.
- **AI.UPS™ Platform**: Patented microgrid control system designed to deliver flickerless, full-facility protection with up to Tier 4 performance for mission-critical facilities.
- **Battery Energy Storage Systems (BESS)**: Grid-scale and commercial & industrial storage solutions for frequency regulation, peak shaving, and renewable integration.
- **Fault-Tolerant Architectures**: Engineered solutions for the most demanding environments, built with Tier-1 components backed by 20-year warranties.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed (private company)
- **Key Metric**: Total Funding: $262.6M (across multiple debt and equity rounds, including Series B led by Ultra Capital in 2023); Annual Revenue: $4.5M (per LinkedIn estimate, likely reflective of earlier stage); 3 GW+ operating & under construction; 10+ GW production capacity
- **Notable Investors/Partners**: Ultra Capital (Series B lead), SDCL Energy Efficiency Income Trust, Lombard Odier Investment Managers, Live Oak Bank, BridgePeak Energy Capital, Pathward
- **Growth Signals**: 143% headcount growth YoY (148 employees as of 2026), 875% job posting growth YoY (52 open positions), 75+ projects across the Americas, $77.6M debt financing in January 2025

## Competitive Advantages
- **Patented Technology**: Proprietary microgrid control systems (AI.UPS) and energy management software (ON.command) that set new global benchmarks for reliability and uptime (99.9% availability).
- **FEOC Compliant & U.S. Manufacturing**: Proudly engineered and built in America, meeting foreign entity of concern compliance – a key differentiator for domestic infrastructure projects.
- **Gigawatt-Scale Supply Chain**: 10+ GW production capacity with Tier-1 components and 20-year warranties, enabling rapid deployment at scale.
- **Track Record**: Over 150 years of combined team runtime, proven performance across industrial, manufacturing, infrastructure, transportation, and grid-scale storage.

## Strategic Focus
- **Grid-Safe AI Power**: Scaling hyperscale power solutions specifically designed for AI data centers, addressing grid volatility and power quality challenges.
- **Global Deployment**: Expanding across the Americas with a fully ramped supply chain and active projects in 9 countries (US, Mexico, Argentina, Peru, Chile, Canada, etc.).
- **Vertical Integration**: Continuing to develop proprietary hardware and software in-house, from R&D to commissioning and asset management.

## Why Work Here
- **Culture**: Described as dynamic, innovative, and far from traditional corporate mold – autonomous teams with high trust, fast decision-making, and a focus on impact. “If you want predictable, this isn’t it. If you want impact, welcome.”
- **Work Environment**: Cross-functional teams spanning engineering, product, finance, and operations. Locations include Miami (HQ), Houston, Mexico City, Atlanta, and field roles across the US. Hybrid/remote flexibility likely varies by role.
- **Growth Opportunities**: Rapidly scaling company (143% headcount growth) with opportunities in supply chain, project engineering, R&D, software, and IT. Emphasis on professional growth and learning from “the brightest minds in technology, product engineering, finance, and more.”
- **Mission-Driven**: Work that directly impacts energy resilience, clean energy adoption, and AI infrastructure – a chance to solve some of the toughest power problems globally.

## Sources
1. [ON.energy Website](https://www.on.energy/)
2. [ON.energy Greenhouse Careers](https://job-boards.greenhouse.io/onenergy)
3. [ON.energy LinkedIn](https://www.linkedin.com/company/on-es)
4. [ON.energy Team Page](https://www.on.energy/team)
5. [CB Insights - On.Energy Profile](https://www.cbinsights.com/company/onenergy)

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