# Companies using TRNSYS

1,633 companies use TRNSYS, based on their job posts and their employees' public profiles. 129 job posts named it from October 2025 to August 2026. Mechanical Engineer roles mention it most.

Data as of November 9, 2026. Source: Sumble.

## Which companies name TRNSYS in the most job posts?

Affiliated Engineers, Inc. leads with 67 job posts naming TRNSYS, followed by Inddigo and CSTB. Inddigo is the newest of the five companies in the table, with its first job post naming it in December 2023.

| Company | Job posts | People | Recent job post |
|---|---:|---:|---|
| [Affiliated Engineers, Inc.](https://sumble.com/orgs/affiliated-engineers) | 67 | 1 | "Ability to use at least one building system simulation tool, including EnergyPlus, IES-VE, TRNSYS, DOE-2 (eQuest), TRACE, CFD, or Radiance, for consulting and analysis." (Building Performance Consultant I, Oct 30, 2026) |
| [Inddigo](https://sumble.com/orgs/inddigo) | 35 | 3 | "La connaissance de logiciels spécifiques au métier est un plus (TRNSYS, Pléiades, DesignBuilder, etc…)" (internship in environmental building quality (EBQ) (m/f), Oct 21, 2026) |
| [CSTB](https://sumble.com/orgs/centre-scientifique-et-technique-du-batiment-cstb) | 33 | 4 | "Vous avez des compétences en modélisation et la maitrise d’un ou plusieurs logiciels de simulation énergétique dynamique (TRNSYS, Energy Plus, Comfie Pleiades, etc.) seraient un plus." (R&D engineer, modeling and data expert, Jun 6, 2025) |
| [dbHMS](https://sumble.com/orgs/dbhms) | 26 | 0 | "Experience with TRNSYS, Grasshopper and other "bug suite" tools, Python, or similar scripting/coding." (Senior Building Performance Analyst, Feb 24, 2026) |
| [ISFH – Institut für Solarenergieforschung Hameln](https://sumble.com/orgs/institut-fur-solarenergieforschung) | 22 | 1 | "…weitere Möglichkeit ist die Durchführung dynamischer Systemsimulationen mit der Software TRNSYS für unterschiedliche Anlagenkonzepte, mit besonderem Fokus auf Wärmepumpensysteme in Mehrfamilienhäusern." (Internship/Thesis: Photovoltaic-thermal (PVT) collectors in combination with heat pumps in residential buildings – stsy042, Sep 23, 2026) |

## Is hiring for TRNSYS growing?

TRNSYS appeared in 0.06 in every 10,000 job posts from June to August 2026, against 0.04 from March to May. These are small numbers of job posts, so a few companies can move them.

| Month | Job posts naming it | All job posts | Per 10,000 job posts |
|---|---:|---:|---:|
| Oct 2025 | 14 | 1,413,673 | 0.10 |
| Nov 2025 | 18 | 1,822,119 | 0.10 |
| Dec 2025 | 14 | 1,236,103 | 0.11 |
| Jan 2026 | 12 | 1,828,002 | 0.07 |
| Feb 2026 | 14 | 1,856,647 | 0.08 |
| Mar 2026 | 10 | 1,850,711 | 0.05 |
| Apr 2026 | 9 | 1,728,886 | 0.05 |
| May 2026 | 5 | 1,821,509 | 0.03 |
| Jun 2026 | 11 | 1,909,496 | 0.06 |
| Jul 2026 | 13 | 1,815,180 | 0.07 |
| Aug 2026 | 9 | 1,835,698 | 0.05 |

## How many companies named TRNSYS in a job post for the first time in recent months?

In the three months to August 2026, 7 companies posted about TRNSYS for the first time. From March to May, 6 did. That brings the companies naming it for the first time since October 2025 to 23, through August 2026.

| Period | Companies naming it in a job post for the first time |
|---|---:|
| March to May 2026 | 6 |
| June to August 2026 | 7 |
| October 2025 to August 2026 | 23 |

Companies whose first job post naming it appeared in that period. Recruiters, staffing firms and job boards are left out.

## How do we know which companies use TRNSYS?

Most of these companies come from employees' profiles: 87% have no job post naming TRNSYS. 58 show up in both job posts and employees' profiles.

| How we know | Companies | Share |
|---|---:|---:|
| Job posts name TRNSYS | 212 | 13% |
| Employees' profiles list TRNSYS | 1,421 | 87% |

## What size are the companies that use TRNSYS?

Companies with 50 to 999 employees are the largest group of TRNSYS users, at 40%. 275 of its companies have more than 5,000 employees.

| Size | Share | Typical tech page |
|---|---:|---:|
| Under 50 employees | 23% | 22% |
| 50 to 999 | 40% | 38% |
| 1,000 to 5,000 | 20% | 17% |
| Over 5,000 | 17% | 23% |

## Where are TRNSYS companies based?

Italy is 7.9 times as common among TRNSYS companies as on the typical tech page, at 12%. France leads overall with 22%. The United States is less common than usual, at 9.5% against 43% on the typical tech page.

| Country | Companies | Share | Typical tech page |
|---|---:|---:|---:|
| France | 354 | 22% | 4.6% |
| Germany | 209 | 13% | 4.4% |
| Italy | 188 | 12% | 1.5% |
| United States | 152 | 9.5% | 43% |
| Spain | 109 | 6.8% | 1.8% |
| Canada | 76 | 4.7% | 3.6% |

## Which roles mention TRNSYS most?

No single role dominates for TRNSYS; Mechanical Engineer leads with 17% of the job posts. The top four roles cover 47% of these job posts.

| Role | Share | Oct 2025 to Aug 2026 | Mar to May 2026 | Jun to Aug 2026 |
|---|---:|---:|---:|---:|
| Mechanical Engineer | 17% | 22 | 1 | 6 |
| Skilled Trades | 16% | 20 | 4 | 5 |
| Researcher | 7.8% | 10 | 0 | 2 |
| Consultant | 7% | 9 | 2 | 0 |
| Performance Engineer | 4.7% | 6 | 2 | 0 |
| Environmental Health & Safety | 3.9% | 5 | 0 | 0 |

## Which companies started naming TRNSYS in job posts recently?

Between April and August 2026, 6 companies with 50 or more employees first named TRNSYS in a job post, 3 of them with more than 5,000 employees.

| Group | Company | Job posts, April to August 2026 |
|---|---|---:|
| Commercial | [Brightcore Energy](https://sumble.com/orgs/brightcore-energy) | 2 |
| Commercial | [Fluidstack](https://sumble.com/orgs/fluidstack) | 1 |
| Commercial | [British Antarctic Survey](https://sumble.com/orgs/british-antarctic-survey) | 1 |
| Enterprise | [Capgemini](https://sumble.com/orgs/capgemini) | 1 |
| Enterprise | [Government of Canada](https://sumble.com/orgs/government-of-canada) | 1 |
| Enterprise | [University of Nottingham](https://sumble.com/orgs/university-of-nottingham) | 1 |

Companies that named TRNSYS in a job post for the first time between April and August 2026, ranked by their job posts in those months. AI-native companies get a group of their own, whatever their size. Recruiters and job boards are left out.

## What else do TRNSYS companies use?

EnergyPlus, Modelica and Dymola show up far more often at TRNSYS companies than at companies of the same size. Next is IES VE: 15% of these companies use it, against 0.15% of similar ones.

| Tool | Companies | Also name it | Typical | Times as common |
|---|---:|---:|---:|---:|
| EnergyPlus | 70 | 45% | 0.18% | 243 times |
| Modelica | 41 | 26% | 0.18% | 145 times |
| Dymola | 17 | 11% | 0.11% | 100 times |
| IES VE | 23 | 15% | 0.15% | 96 times |
| eQuest | 15 | 9.6% | 0.16% | 62 times |
| InfoWorks | 10 | 6.4% | 0.15% | 44 times |
| Pyomo | 10 | 6.4% | 0.17% | 38 times |
| Simscape | 10 | 6.4% | 0.19% | 33 times |

Shares are out of the 157 companies whose job posts name TRNSYS, not counting firms whose job posts name almost every technology.

## About this data

Sumble built this page. Sumble gives sales, marketing and other GTM teams technographics and hiring signals for the companies they sell to: the technologies each company uses, which teams are hiring and for what, and who reports to whom. That helps a team know who to contact, why now, and what to say.

Sumble covers more than 3.6 million companies, 93 million job posts collected since 2022 and 194 million employee profiles, and tracks more than 37,000 technologies. It finds which technologies a company uses by reading its job posts and its employees' public profiles.

Sumble has a free plan, and the same data is available through its API and MCP server.

A company counts when its own job posts or its employees' public profiles name the technology. Hiring is that technology's share of all job posts collected each month. Quotes are copied word for word from the companies' job posts.

Every figure on this page comes from Sumble's own analysis, and you won't find it outside Sumble.