
Websitephelas GmbH
phelas is developing the next generation of Liquid Air Energy Storage (LAES), to make sure renewable energy becomes available 24/7 in the world. Our second pillar Catalyst helps energy companies to deploy storage profitably already today.
Overview
As an Energy Optimization Engineer, you will join our Tech team and work at the intersection of software development, energy markets, and optimization modeling. Your main mission is to design and implement new features for our Catalyst software – enabling investment-grade modeling of energy storage and hybrid projects. You will collaborate closely with software developers (frontend & backend) and engage with customers to translate their needs into robust solutions.
Starting date: Immediate / Jan 2026
Salary: 45 to 59 k
About us
phelas is developing the next generation of Liquid Air Energy Storage (LAES), to make sure renewable energy becomes available 24/7 in the world. Our second pillar Catalyst helps energy companies to deploy storage profitably already today.
When you work at phelas, no day will be the same for you or your colleagues. With our 15+ growing team, you will shortly know everyone and work together with a diverse set of Engineers and specialists in their fields of work from all over the world. We are extremely proud of our diverse workforce and highly value an inclusive work environment while spearheading towards a more sustainable future.
Your Role
- Develop and extend optimization models for storage dispatch (e.g., MILP, linear optimization).
- Implement new features in close collaboration with software engineers.
- Analyze and model European power markets (Day-Ahead, Intraday, ancillary services).
- Support financial and techno-economic evaluations of storage projects.
- Interact with customers to understand their challenges and translate them into product improvements.
- Contribute to UX/UI improvements through analytical feedback and feature ideas.
Your Profile
Needed skills:
- Ability to write clean, maintainable Python code (object-oriented & project-based).
- Capability to formulate and solve optimization problems, especially MILP, using tools like Gurobi, CPLEX, or Pyomo.
- Skill in handling and analyzing large datasets (time series, market data).
- Confidence in building financial and techno-economic models in Excel or Python.
- Understanding of energy markets mechanisms, specifically Day-Ahead, Intraday, and balancing markets in Europe.
- Ability to research, interpret and apply regulatory rules in energy market modeling.
- Translating customer requirements into technical features.
Experience:
- Built and deployed Python applications in real projects.
- Applied optimization models (MILP) to real-world or realistic datasets.
- Worked with energy market data (prices, load, balancing) for analysis or modeling.
- Delivered end-to-end projects: data prep → modeling → interpretation.
- Collaborated in multi-disciplinary teams and contributed to product development.
- Translated technical results into customer-relevant insights or features.
Specific knowledge:
- European power markets (Day-Ahead, Intraday, balancing).
- Energy storage dispatch principles and project economics.
- Basic regulatory context in European electricity markets.
Hard skills:
- Strong Python coding (object-oriented).
- Mathematical optimization (MILP, Gurobi/CPLEX/Pyomo).
- Data analysis & modeling (time series, financial/techno-economic).
- Translating customer requirements into technical features.
Soft skills:
- Analytical, problem-solving mindset.
- Clear communicator, able to simplify complexity.
- Team player, comfortable in interdisciplinary settings.
- Customer-oriented and proactive.
Language skills:
- English is mandatory
Our offer
- Participation in company growth (employee stock program).
- Dynamic startup environment with high ownership and creative freedom.
- Flexible working hours & hybrid / remote options.
- Munich headquarters – one of Europe’s most liveable cities.
- A diverse, interdisciplinary, and international team with a shared mission to accelerate the energy transition.
To apply for this job please visit app-eu.wrike.com.