Elise Keller

Elise Keller · Chief Technology Officer · Europe

From electrical response to technology responsibility

Chief technology officer

Rovenkel Energy

Sector
Wind and solar generation, storage development and industrial-heat services
Ownership
Pension investment vehicle 60%; founding family 40% since 2018
Company scale
€1.6 billion revenue in 2025
Employees
1,900 employees in 2025
Geography
Essen headquarters; Germany, the Netherlands and Denmark; 3.1 GW gross wind and solar capacity in 2025
Reporting to
Chief executive Anselm Veyrath
Team
118 employees through five direct reports; 22 contractors separately
Financial scope
2026 authority €72 million: €44 million technology development and €28 million qualification

Mandate

Lead the selection and qualification of energy technologies against defined commercial and operating duties.

Outcomes

  • Reframed storage procurement around a specified delivered-energy duty.
  • Funded investigation and repetition of an unresolved inverter scenario before the next study stage.
  • Kept a first-phase wind-control observation out of the annual production plan while extending the investigation.

Decisions in context

I became CTO as Rovenkel's technology choices increasingly crossed generation, storage and industrial heat. The appointment gave me responsibility for the engineering recommendation and the capability used to qualify it, while asset operations retained operating accountability. I report to Anselm Veyrath and work closely with Maren Solbrecht when a proposal changes the duty that an operating team would inherit. My current authority covers development and qualification; it is not the company's full construction budget. Recent decisions have required me to reduce a storage reference power figure, extend an inverter investigation and resist a premature annual benefit from a wind-control trial. I present such choices to the board as an executive, without holding a director seat. The role has strengthened my ability to distinguish a useful next commitment from a conclusion that the evidence cannot yet support. It has also made the financial and organisational cost of further learning part of the recommendation.

Reason for the move

Current role; considering a compatible first external board appointment.

Director of technical development

Rovenkel Energy

Sector
Renewable-generation development and early industrial-heat studies
Ownership
Founding family until 2018; pension investment vehicle 60% and family 40% thereafter
Company scale
€1.05 billion revenue in 2020
Employees
1,450 employees in 2020
Geography
Germany, the Netherlands and Denmark; 2.3 GW gross generation capacity in 2020
Reporting to
Chief technology officer
Team
78 employees through four direct reports by December 2020
Financial scope
€31 million annual development authority in 2020

Mandate

Develop technology alternatives and connect engineering studies with staged project decisions.

Outcomes

  • Introduced separate recommendations for further engineering and construction commitment.
  • Brought thermal-service assumptions into early technology comparisons.
  • Expanded review responsibilities across generation technology and development engineering.

Decisions in context

This appointment broadened my work from a technical discipline to the development choices facing the business. I led engineers preparing alternatives for projects whose commercial interest could run ahead of the available evidence. I required recommendations to identify the stage being funded, the assumptions that mattered and the decision that would follow. That helped distinguish a study intended to reduce uncertainty from a construction proposal expected to carry a much larger commitment. The company's 2018 ownership change increased the need to explain our development account to investors with different perspectives, but it did not alter the physical questions the equipment had to answer. I worked under the CTO and developed four direct reports who could connect specialist findings with the wider proposal. My title included director, yet I held no board seat. The next step into the CTO role followed this broader responsibility for technology selection, qualification capability and the consequences of our recommendations.

Reason for the move

Promoted to CTO in January 2021.

Concurrent appointment

The director title described an executive employment position, not a statutory board appointment.

Head of power conversion

Rovenkel Energy

Sector
Onshore wind and emerging solar generation
Ownership
Founding-family-owned business
Company scale
€460 million revenue in 2013
Employees
720 employees in 2013
Geography
Germany and the Netherlands; 0.95 GW gross generation capacity in 2013
Reporting to
Director of engineering
Team
36 employees through three direct reports by December 2013
Financial scope
€9 million annual discipline authority in 2013

Mandate

Build power-conversion engineering capability and coordinate qualification of equipment interactions.

Outcomes

  • Established documented comparisons between expected and measured equipment response.
  • Separated component descriptions from the conditions of the intended electrical system.
  • Developed three engineering managers to lead qualification reviews.

Decisions in context

I took responsibility for a discipline whose equipment could not be understood solely through its own product specification. The surrounding electrical system and the selected control settings mattered to the result. I led a team that worked with suppliers, development engineers and operations to examine those interactions and explain departures from the expected response. My management task was to make an unexpected finding discussable without turning every discrepancy into an immediate rejection of the technology. By the end of the period, I led thirty-six employees through three direct reports and held nine million euros of annual authority. Those figures describe the discipline in 2013. I was not responsible for the company's entire generation portfolio or construction expenditure. The role prepared me for technical development by showing how a well-supported specialist conclusion could still leave a larger project decision open. I moved on to lead that connection between engineering investigation and the alternatives a business could reasonably pursue.

Reason for the move

Moved into technical-development leadership in January 2014.

Generation technology lead

Rovenkel Energy

Sector
Onshore-wind generation and project development
Ownership
Founding-family-owned business
Company scale
€180 million revenue in 2006
Employees
310 employees in 2006
Geography
Germany; 0.42 GW gross generation capacity in 2006
Reporting to
Engineering manager
Team
14 employees through two direct reports by December 2006
Financial scope
€2.6 million annual technology authority in 2006

Mandate

Evaluate generation equipment and make technical assumptions usable for procurement and operations.

Outcomes

  • Introduced equipment-comparison records with explicit operating conditions.
  • Connected supplier investigations with the duty expected by the asset team.
  • Established review ownership for technical assumptions carried into procurement.

Decisions in context

I joined Rovenkel because I wanted to understand what happened after an equipment recommendation was accepted. The generation owner had to operate the resulting system, maintain its service and explain its performance over time. I worked under the engineering manager and gradually built a team of fourteen employees, with two direct reports by the end of the appointment. My work brought procurement and operating colleagues into equipment comparisons that had previously been presented mainly as technical choices. I learned that a component's lower price and an operator's preference for familiarity could each be reasonable without settling the integration question. The comparison needed to preserve those consequences rather than declare one function's account complete. I developed the practice of naming the operating conditions beside the result and assigning ownership to assumptions that would travel into procurement. That experience led to a broader discipline role as the company expanded its generation technologies and required more structured power-conversion capability.

Reason for the move

Promoted to head of power conversion in January 2007.

Electrical controls engineer

Elsira Controls

Sector
Industrial electrical controls and conversion engineering
Ownership
Privately owned engineering company
Company scale
€38 million revenue equivalent in 1999
Employees
260 employees in 1999
Geography
Germany; engineering assignments for industrial customers
Reporting to
Lead electrical engineer
Team
Individual contributor in a six-person engineering group; no direct reports
Financial scope
No delegated budget or investment authority

Mandate

Develop and examine electrical-control work under the lead engineer's supervision.

Outcomes

  • Prepared test records that stated configuration and observation conditions.
  • Investigated differences between expected and observed control response.
  • Supported handovers that distinguished test settings from intended service conditions.

Decisions in context

I entered this role immediately after completing my electrical-engineering degree. My responsibility was technical contribution, not departmental leadership. I worked within a six-person group, reported to the lead electrical engineer and held no delegated budget. The assignments taught me to preserve enough of the test configuration that another engineer could understand what an observation meant. I learned to discuss a discrepancy before knowing whether its explanation lay in the equipment, the settings or the assumptions used to describe the surrounding system. Those habits became the basis of my later qualification work, but I do not attach my current authority to this early appointment. I also began to understand the limits of a supplier-side view: an equipment investigation could be complete while the customer's operating obligation remained only partly described. I left in December 1999 to join Rovenkel, where I could work with the generation owner responsible for the consequences of the technology choice over its operating life.

Reason for the move

Joined a generation owner to work closer to equipment selection and operating duty.

What I am looking for next

I am considering how my technology experience could contribute to a first external board appointment alongside my executive role. The most useful setting would be an energy or industrial business facing substantial choices about equipment, development evidence and long-lived operating obligations. I would not seek to become a parallel engineering department. I would help directors examine whether the technical recommendation answers the service question, what remains outside its evidence and how the next commitment has been framed. I can propose twenty-two days annually, subject to employer consent, relationship review and a committee calendar that includes preparation and site learning. I hold no existing director appointment. A serious discussion would need to cover the company's financial position, asset condition, investor expectations and the experience already present around the board table. I would expect induction in the duties and context of the particular company before presenting my executive familiarity with board discussions as readiness for the different responsibility of collective oversight.