---
title: 'Thermal Engineer at Last Energy'
canonical: 'https://feeny.ai/job/thermal-engineer-last-energy-austin-z94r02xvm7r5'
type: 'job'
last_seen: '2026-10-20'
---

# Thermal Engineer at Last Energy

- **Company:** Last Energy
- **Location:** Austin, TX
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-10-01
- **Last confirmed live:** 2026-10-20
- **Apply:** https://jobs.lever.co/last-energy/e97368a5-50af-4ab7-b2b0-3403e2c14bb4

## Job description

Last Energy is a pioneering US technology company focused on fleet-wide deployment and operation of next-generation nuclear assets. We are revolutionizing nuclear power delivery for rapid deployment and scalability. We are seeking a Thermal Engineer to design the pressure-boundary hardware in our micro nuclear power plant, built on proven pressurized water reactor (PWR) technology. That means heat exchangers, piping, pressure vessels, and the primary loop that connects them. This is a hardware role. The engineer in this seat turns thermal performance requirements into components that can be manufactured and deployed, starting from hand calculations and first principles, and saving detailed analysis for detailed design. Working alongside our analysis and structural engineers, this person takes designs from model to physical hardware.

## Key Duties & Responsibilities

- Lead the conceptual design, analysis, and execution of critical thermal-mechanical components and systems for our advanced power plant
- Drive mechanical design of components subject to thermal loading
- Own the design of heat exchangers, piping networks, fluid storage tanks, and other pressure-boundary equipment, and partner with our structural engineers on validation, ensuring structural integrity, thermal performance, and design safety across key reactor components
- Perform thermal and structural analyses (thermal stress, fatigue, and thermal expansion) to validate component designs against pressure, temperature, and cyclic loading requirements
- Contribute directly to the mechanical design and optimization of critical thermal components, translating thermal performance requirements into manufacturable, deployable hardware
- Collaborate daily with a multidisciplinary team to integrate thermal-mechanical solutions into cohesive, plant-level designs
- Support material selection, tolerancing, and design-for-manufacturing decisions for components operating under high-temperature and high-pressure conditions
- Operate autonomously, driving projects from concept to design verification in a startup culture that values speed, ingenuity, and accountability

## Qualifications

- BS or MS in Mechanical Engineering or related field, with 7+ years of hands-on industry experience designing components under thermal and mechanical loading
- Proven experience as a Mechanical, Thermal, or Design Engineer working on thermal systems components within power plant, nuclear, or complex industrial systems
- Proficiency in 3D CAD software (e.g., Autodesk Inventor, SolidWorks, Siemens NX, PTC Creo) for mechanical design of thermal-mechanical components and assemblies
- Proficiency in analysis software (e.g., ANSYS Mechanical, Abaqus, SolidWorks Simulation) for structural and thermal stress analysis
- Solid working knowledge of heat transfer, thermodynamics, and mechanical design principles (fatigue, fracture, thermal expansion, pressure-boundary design)
- Experience with pressure vessel or piping design codes a strong plus (ASME BPVC Section III/VIII, B31.1/B31.3)
- Practical, hands-on approach to problem-solving with a bias toward manufacturable, deployable designs over purely academic analysis
- Excellent communication skills and a willingness to work collaboratively in a cross-functional, startup team environment

## About Last Energy

## Company Overview
- **One-liner**: Last Energy develops and deploys micro modular pressurized water reactor (PWR) power plants using a full-service, factory-built model to deliver clean, reliable, on-site baseload electricity for industrial customers and utilities.
- **Entity Type**: Private (Venture Capital-Backed, Series C)
- **Headquarters**: Austin, Texas, USA (also has an office in Washington, D.C.)
- **Founded**: 2019
- **Founders**: Founded by the Energy Impact Center (EIC), led by Bret Kugelmass [lastenergy.com/about](https://www.lastenergy.com/about)

## Core Business
- **Primary industry**: Nuclear power generation, clean energy infrastructure, climate technology
- **Target customers**: B2B – data centers, energy-intensive industrial facilities, utilities seeking behind-the-meter or on-premises baseload power [lastenergy.com](https://www.lastenergy.com/)
- **Mission**: “How to deliver abundant, reliable energy fast enough to support modern industry and economic growth” [lastenergy.com/about](https://www.lastenergy.com/about)

## Products & Services
- **PWR-20**: A 20 MWe micro modular nuclear reactor based on proven pressurized water reactor technology. The plant is fully factory-fabricated, uses proprietary steel containment, and is designed for rapid on-site assembly. Last Energy acts as designer, owner, operator, and independent power producer, selling power under long-term purchase agreements [lastenergy.com](https://www.lastenergy.com/)

## Market Standing
- **Valuation / Market Cap**: Not publicly disclosed (private company)
- **Key Metric**: Total disclosed funding raised is **$324 M**; latest round was a **$101 M Series C** completed on July 18, 2025 [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
- **Notable Investors**: AE Ventures, Astera Institute, Chaucer Global, Dysruptek, Endowment Arm [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
- **Growth Signals**: 
  - 60 employees and growing [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
  - 15 active patents, with several recently filed for containment structures [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
  - Company status is “Generating Revenue” [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
  - Active hiring for key operational roles in Austin, TX [jobs.lever.co](https://jobs.lever.co/last-energy)

## Competitive Advantages
- **Full-service delivery model**: Last Energy designs, builds, owns, and operates its plants, removing the need for customers to develop or finance nuclear assets.
- **Proven reactor technology**: Uses standard PWR technology (not novel) combined with factory modularization to reduce construction time and cost.
- **Proprietary steel containment**: Patented containment structures improve safety and simplify siting.
- **Behind-the-meter IPP structure**: Power purchase agreements provide stable revenue while customers get reliable, carbon-free baseload power without capital outlay.

## Strategic Focus
- Scaling the deployment of micro modular reactors to meet soaring electricity demand from AI, data centers, and industrial reshoring.
- Expanding factory production capabilities to accelerate time from order to operation.
- Growing its portfolio of power purchase agreements with utilities and large energy consumers.

## Why Work Here
- **Culture**: “Dynamic and passionate team that blends fresh perspectives with seasoned expertise” — described as a fast-growing international team united by a mission to solve one of the hardest problems in energy [lastenergy.com/careers/jobs](https://www.lastenergy.com/careers/jobs)
- **Work policy**: Roles are currently on-site in Austin, TX or Washington, D.C. [jobs.lever.co](https://jobs.lever.co/last-energy)
- **Impact**: Opportunity to work on the “most important challenge of our lifetime” with tangible progress toward global clean energy goals.
- **Engineering culture**: Hands-on work with hardware, nuclear systems, and modular manufacturing; strong patent activity indicates a culture of innovation.

## Sources
1. [lastenergy.com](https://www.lastenergy.com/)
2. [lastenergy.com/about](https://www.lastenergy.com/about)
3. [lastenergy.com/careers/jobs](https://www.lastenergy.com/careers/jobs)
4. [pitchbook.com](https://pitchbook.com/profiles/company/265186-36)
5. [jobs.lever.co](https://jobs.lever.co/last-energy)

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