Thermal Engineer

The Thermal Engineering role at Lunar Energy is a key position within a company where thermal system performance is core to company success. Lunar is looking for an engineer with broad experience in thermal system modeling, testing, and design. Experience rapidly developing and ramping innovative products with complex thermal behavior to high volume production. An engineer with outstanding organization and communication skills, the ability to drive schedules and solve technical challenges quickly. If (when) there is a problem, to be hands-on in the lab or on the line, or assisting cross functional teams to solve the issues. 

Lunar Energy was founded to transition homes to 100% clean energy—making our electricity greener, our air cleaner, and our energy more safe, secure and reliable for all. We're a fast-growing, well funded, global company building the world's best clean energy products to electrify all homes and connect communities to form clean, resilient virtual power plants. Lunar offers both a hardware and software solution approaching home energy storage from both the consumer’s and utilities perspective to provide the most reliable and advantageous energy storage products.

On a given day at Lunar, you’ll likely…

  • Develop detailed simulation models for all of Lunar's power conversion systems
  • Create, design, implement, and validate system thermal design through simulation, analysis and testing
  • Identify the correct analysis level for the task at hand ranging from a simple hand calculation to 3D simulation
  • Define and execute test plans to validate component and system performance
  • Drive the design details, schedules, and issues resolution across multiple products, subsystems, and teams helping those who need help to achieve milestones
  • Communicate proposals, results, and specifications through clear, information-rich data visualizations
  • Work with the firmware and controls engineers to integrate the thermal control algorithms into firmware
  • Use simulation and test data from first generation designs to improve next generation products
  • Work with vendors to deliver components and hardware that meet design requirements

Desired Skills:

  • MS or PhD in Mechanical Engineering
  • 8-10 years of experience in designing, simulating, testing, and developing thermal systems
  • Strong desire to launch products going to great lengths to be successful
  • Experience with Python and/or Matlab for data analysis, simulation, design, and building 1D physics based models
  • Fundamental knowledge in CFD/FEA concepts and ability to apply in simulations
  • 3D CAD experience. Onshape experience is a plus.
  • Successful track record working with cross functional teams (EE, FW, GSM, Mfg Eng, Operations, Quality, etc) to develop products and take to manufacturing
  • Motivation to grow current knowledge and skills and own components or products from end to end
  • Troubleshooting skills to resolve issues through the development process with attention to detail for function and cost
  • Experience in value engineering and ability to achieve high levels of form, fit, and function at the most efficient cost
  • Ability and inclination to dive deep with the team to find solutions and turn things around quickly when problems and blockers come up
  • Electrical systems knowledge and basic understanding of electrical circuits and power systems
  • Data acquisition using Labview and National Instruments hardware
  • Lab experience including designing tests, executing test plan, and analyzing results to publish a conclusion
  • Expertise in thermal management of power electronics and battery systems is a plus. 
  • Relevant renewable energy product development experience is a plus
  • Strong data visualization and technical communication skills
  • Demonstrated excellence managing the development of complex thermal systems


We’re dedicated to creating a remarkable employee experience. At Lunar, competitive base pay is one part of our total compensation package. Lunar employees also have the opportunity to become Lunar shareholders by getting equity in a fast-growing company and participating in our employee stock program.

Additional benefits include: 

  • Medical, dental, and vision insurance for employees and dependents
  • Flexible Paid Time Off plus paid holidays
  • Tax deferred 401(k) plan 
  • Paid parental leave for all full time employees including 12 weeks paid parental leave for the birthing mother and 6 weeks paid parental leave for the non-birthing parent 
  •  Subsidized EV charging and pre-tax commuter benefits
  • Cell Phone stipend 

Our DE&I Philosophy: Lunar Energy is an equal opportunity employer. We are committed to attracting, developing and retaining diverse talent by supporting an inclusive workplace. Lunar recruits, hires, trains, promotes, compensates, and administers all personnel actions without regard to race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, disability status or any other status protected by applicable law.

Our Compensation Philosophy: Our goal is to ensure that all Lunar Energy employees are fairly compensated. Please note that the salary range information that follows is a good faith estimate for this position provided pursuant to the Pay Transparency for Pay Equity Act for California applicants. The salary range estimate for this position depending on level of experience is $140,000-$190,000 USD

The actual offer, reflecting the total compensation package & benefits, will be at the company’s sole discretion, and determined by factors including but not limited to years of experience, job level, geographic location, and other relevant business considerations. The company also reserves the right to amend or modify this job description, employee perks, and benefits at any time.


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