A 42-Person Startup Is Paying $250K for Power Electronics Leads

Eighteen Open Roles, Two Hubs, One Architecture

Exowatt, a 42-person startup—BuiltIn's data shows 42 total employees—backed by $105 million across five rounds, has 18 open roles (Lever's listings show 18) across Miami and Austin to take its modular thermal energy storage system into rate production. The careers page frames the mission: "make sustainable renewable energy always available and almost free." The roles beneath it tell a concrete story: the company is staffing for production, not prototypes.

The openings split across Miami and Austin and cluster around the physics of the P3 module: concentrated solar collection, high-temperature thermal storage, and the power electronics that turn stored heat into dispatchable electricity. Mechanical engineering carries the heaviest load. Four lead mechanical roles (two in heat exchangers, two in structures, duplicated across both cities) signal that the thermal core and its mechanical packaging are moving from design into iteration and test. Optical engineering follows close behind: a lead optical engineer, a mechanical engineer for optical systems, an optomechanical integration and test engineer, and a manufacturing/NPI engineer for optics all sit in Miami, where the solar tracker platform lives. Controls and firmware get a single lead in Austin, but the scope is wide: PLC programming, embedded firmware, industrial communications, CI/CD pipelines, HIL test benches, and EMS/SCADA integration for a scalable thermal storage system. Power electronics gets its own lead in Miami, targeting MW-class multi-port conversion. Thermal design, power systems modeling (EMT simulation and test validation), and electrical engineering round out the core technical spine.

Manufacturing and quality appear in force for a company this size. A contract technician for manufacturing and assembly in Austin, a quality and reliability engineer in Austin, and a technical program manager for supply chain and manufacturing (posted 22 hours ago as of mid-September, LinkedIn's posting shows) show the supply chain hardening. The lone HR role, a senior HR business partner on a contract-to-hire basis in Austin, sits embedded with engineering and operations leadership, advising on org design, performance management, and compensation. A general talent-network application rounds out the 18.

The duplicated lead roles in Miami and Austin suggest parallel execution tracks — optical and electrical in Florida, thermal-mechanical and controls in Texas — converging on a single product architecture. The P3 module, described in job postings as integrating into grid, behind-the-meter, and microgrid sites, demands balance-of-plant design that spans civil, structural, and interconnection engineering. The optical roles point to concentrated solar collection at scale. The controls role describes a full-stack industrial automation stack, not a research-grade test rig. The manufacturing and quality hires confirm that supplier qualification, non-conformance processes, and NPI support are active workstreams.

Salary bands posted on Zero G Talent's board for the newest mechanical leads ($150k–$215k for structures, $150k–$215k (Miami) to $180k–$215k (Austin) for heat exchangers) sit above typical early-stage hardware ranges, and the board's median across five salaried roles lands at $215k. The controls lead bands at $125k–$185k, Zero G Talent's figures put them. Equity, unlimited PTO, paid relocation, and comprehensive healthcare appear on every listing, Exowatt's careers page shows. The compensation detail, the geographic split, and the functional weight toward thermal-mechanical and optical systems all point to the same conclusion: Exowatt is building the team that takes a validated architecture into rate production.

Inside the Screening Funnel

Exowatt's hiring funnel starts before a human ever sees your resume. The company's Lever careers portal discloses that AI tools "review applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information." Those tools assist the recruitment team but do not replace human judgment; final hiring decisions are made by people. Candidates should assume their first pass is algorithmic, so keyword alignment with the job description and clean, verifiable formatting are table stakes.

The company's values statement shows that behavioral alignment carries weight alongside technical depth. Recruiters are incentivized to close roles. Candidates should break the ice early, answer "tell me about yourself" in a few sentences covering who you are, what you do, and what you want, and have STAR-method examples ready. Asking the recruiter about their own experience at the company builds rapport.

Practical logistics matter. Exowatt's two-week timeline suggests a compressed process. Be five minutes early, dress one level above the role, limit total prep to one hour, and never give a salary number first; instead ask, "Do you happen to have a budget for the role just so I know if we're aligned?"

After the loop, a concise, specific thank-you note referencing a concrete discussion point is expected. The decision comes from humans weighing technical signal, values fit, and how clearly you communicated both.

What the Descriptions Demand

The job descriptions show Exowatt hiring for a hardware-first energy company that treats software as a first-class engineering discipline, not an afterthought. Across the 17 open roles, the skill clusters map directly to the three technical pillars of its modular P3 system — thermal energy storage, optical concentration, and power conversion — plus the manufacturing and quality infrastructure to ship them at scale.

Mechanical and structural engineering dominate the lead-level openings. The two Lead Mechanical Engineer (Structures) roles (Austin and Miami) call for FEA modeling, detailed drawing packages, material selection, and manufacturable designs that survive both stationary and moving renewable energy systems. The Lead Mechanical Engineer (Heat Exchangers) role adds CFD simulation, high-temperature validation testing, and supplier collaboration during development and deployment. Creo and SolidWorks appear by name; hand calculations are expected alongside simulation. These are not abstract design seats; the descriptions emphasize CAD-to-prototype cycles, test-stand commissioning, and troubleshooting electromechanical issues on the floor.

Controls and firmware sit at the same seniority tier. The Lead Controls & Firmware Engineer role requires PLC programming, embedded firmware development, industrial communication protocols, CI/CD pipelines for hardware-in-the-loop test benches, and EMS/SCADA integration. Python automation appears repeatedly, not for web services but for test-campaign scripting, sensor calibration, data acquisition, and uncertainty quantification against raytrace models. One optical test engineer description explicitly asks for "agent-run capable" systems, showing that AI-assisted scripting and analysis are already part of the daily workflow.

Optical and photonic skills form a distinct cluster. The optical test engineer role demands bench-to-outdoor test stand design, on-sun campaign planning, sensor instrumentation, and direct comparison of measurements to raytrace models. The Manufacturing/NPI Engineer (Optics) role (posted September 4, 2026) points to new-product introduction for optical subassemblies, bridging design intent to production repeatability. This is precision hardware: alignment tolerances, thermal drift characterization, and automated acquisition loops that can run unattended.

Power electronics and grid integration round out the hard-tech stack. The Lead Power Electronics Engineer (MW-Class Multi-Port Power Conversion) role (listed on LinkedIn August 18, 2026) shows Exowatt is building its own conversion topology, not buying boxes. The balance-of-plant engineer role covers transformer and switchgear specification, protection coordination, power system modeling, interconnection compliance, and utility/EPC coordination: the full grid-interconnection toolkit.

Manufacturing and quality skills reflect a company moving from prototype to rate production. The Quality Engineer role owns those processes new-product-introduction quality gates. The Technical Program Manager (the supply chain and manufacturing function) role (posted September 17, 2026) sits above the factory floor, coordinating cross-functional delivery. Contract technician listings for manufacturing and assembly confirm a production line that is already running shifts.

Two cross-cutting themes appear in every senior description. First, AI-era fluency: "integrate AI agents for scripting and analysis," "agent-run capable," "redefine energy for the AI era"; the language is consistent across mechanical, optical, and controls roles. Candidates who treat large language models as productivity multipliers for simulation setup, test automation, and documentation will match the stated workflow. Second, speed with rigor: "iterate quickly between simulation and hardware," "push through challenges with grit," "operate with speed, precision, and purpose." The company's own career page frames this as cultural expectation, not aspiration.

The modular, full-stack renewable energy playbook now requires engineers who can move fluidly across thermal, optical, electrical, and software domains and who can hand off designs to a supply chain that ships hardware, not slides. Exowatt's descriptions set a higher bar for interdisciplinary depth than most series-B climate startups.

Pay, Equity, and the Fine Print

Exowatt's compensation structure reflects a company that raised $105 million across five rounds (Seed: a16z, Atomic, Altman; Series A: Felicis, HSBC debt) and now employs roughly 42 people across Austin and Miami, BuiltIn's count confirms. The salary bands posted on its open roles span a wide range, from $90,000 for a Mechanical Engineer focused on optical systems in Miami to $250,000 at the top end for a Lead Power Electronics Engineer handling the conversion topology. Most lead-level engineering roles cluster between $145,000 and $215,000, with the highest bands reserved for power electronics and heat-exchanger specialists.

First-party board data from Zero G Talent confirms the lead mechanical bands and adds Miami equivalents: Lead Mechanical Engineer – Structures in Miami lists at $150,000 – $215,000, while Lead Mechanical Engineer – Heat Exchangers in Miami shows $150,000 – $215,000 (versus $180,000 – $215,000 in Austin). The board also notes a typical band of $135,000 – $215,000 for the Technical Program Manager role, with a median of $215,000 across five salaried postings. These figures are current as of September 2026 and supersede the earlier June–July postings where ranges differ.

Equity is listed as a standard component on every role. Exowatt's careers page describes "team-wide equity" alongside comprehensive healthcare and flexible PTO. The company does not publish strike prices or grant sizes. Benefits are explicit: unlimited PTO, health insurance, paid relocation, and equity. The careers page frames these as "competitive benefits to support your well-being." Unlimited PTO and paid relocation are notable for a hardware company that requires on-site presence in either Austin or Miami; relocation assistance signals willingness to recruit nationally for specialized roles like power electronics and optical engineering. Health insurance is described as "comprehensive" but plan details (HDHP vs. PPO, employer contribution percentage) are not public.

The overall package positions Exowatt above early-stage climate-tech norms, where base salaries often top out around $160,000 for senior ICs. TechCrunch notes that if Exowatt delivers on its promise, it "could upend the data center market and broader energy world."

Candidates should ask for the current 409A valuation, option pool refresh policy, and whether equity grants are ISO or NSO. They should also clarify the unlimited PTO culture — hardware teams in integration and test phases often struggle to take time off — and confirm relocation caps for Miami vs. Austin moves. The salary bands are transparent; the equity economics are not.

Seven Moves That Get You Past the Screen

Exowatt is not hiring for abstract potential. It is hiring to commission a factory in Austin, deliver first commercial P3 units in 2025, and clear an 85 GWh backlog, all while iterating on a thermal-storage architecture that went through more than 50 design variants before the founders settled on the current heat-battery approach. The screening process reflects that urgency.

Lead with hardware shipping evidence. Every open role — Lead Mechanical Engineer (Structures), Lead Mechanical Engineer (Heat Exchangers), Lead Controls & Firmware Engineer, Technical Program Manager (Supply Chain & Manufacturing) — sits on the critical path to volume production. The job descriptions explicitly call for experience taking products from prototype through DFM/DFA to rate production. If you have shipped a thermal, mechanical, or electromechanical system at scale (solar trackers, battery packs, HVAC heat exchangers, automotive thermal modules), put the program name, your scope, the annual volume, and the yield metric in the first bullet of your resume. Exowatt's founders (Hannan Happi from Siemens, GE, and Tesla; Jack Abraham from Atomic) know what a production ramp looks like. They will spot resume padding in the first screen.

Demonstrate fluency in the thermal-to-electric chain. The P3 captures sunlight with Fresnel lenses, stores energy as high-temperature heat in a proprietary thermal battery, and dispatches electricity via a heat engine. That is a niche physics stack. Candidates who can speak to heat-exchanger fouling, thermal-stress cycling in ceramic or metallic storage media, ORC or Stirling cycle efficiency at partial load, and control-loop design for thermal inertia will move faster through the technical panel. The Lead Controls & Firmware role specifically asks for real-time control of thermal systems, not generic embedded Linux. If your background is pure firmware, pair it with a project where you closed the loop on temperature or pressure in a physical plant.

Show you can operate inside a domestic supply chain. Katherine Boyle at a16z cited U.S. manufacturing and supply-chain resilience as investment theses. The Technical Program Manager role is built around qualifying domestic vendors for high-temp alloys, specialty glass, and thermal insulation, and doing it on a startup timeline. If you have negotiated blanket orders, managed PPAP/FAI for custom castings, or dual-sourced critical components to avoid single-point failures, quantify it. That language matches the problem set.

Prepare for the in-person mandate. Every current listing states "On-site" for Austin or Miami. The company is explicit: "You'll help build a factory — literally." Remote-first candidates should not apply unless they are ready to relocate (paid relocation is a listed benefit). In the phone screen, be ready to name a start date. Hesitation on location is a fast filter.

Reference the investor and customer signals. The $105M total raise and the 85 GWh backlog are public. Mentioning them in a cover letter or interview signals you have done the homework and understand the business constraints, not just the engineering.

Equity mindset. The careers page lists equity alongside unlimited PTO, health insurance, and paid relocation. At a $105M-funded, pre-revenue hardware company, equity is a meaningful component. Ask about the strike price, the option pool refresh policy, and the liquidation preference stack. Smart candidates treat the equity conversation as a diligence item, not a perk.

Speed matters. Happi has described the company culture as "engineering excellence, rapid iteration, a willingness to spend big to win," language borrowed from F1 but applied to factory commissioning. In the onsite loop, expect a working session. Come with a laptop ready to open your CAD, simulation, or PLM tools of choice. The team evaluates how you think under time pressure, not how you present a slide deck.

One final filter: The mission, as described earlier, is the design constraint. Every engineering decision trades off capital cost, round-trip efficiency, and dispatch duration against that target. Candidates who frame their experience in those terms speak the company's language. That is what gets you past the screen.

Working in frontier tech? Zero G Talent tracks the openings: see every open Exowatt role, browse frontier tech jobs, the companies hiring, and the people building the field.