Ennex is a multi-skilled project development company bringing together core skills needed to develop, secure and execute projects. Ennex has a truly entrepreneurial spirit and prides itself on the fact that the company can react swiftly to market changes, the economic climate and changes in technology. Bringing together engineering and financial industry knowledge makes Ennex a trusted, flexible and dynamic group of people.

Gideon Greyvenstein – Executive Director


Gideon holds a PhD in mechanical engineering and a Masters in Business Leadership (MBL). He is also registered as a professional engineer with the Engineering Council of South Africa (ECSA).  He started his career as an engineer-in-training at the Uranium Enrichment Corporation of South Africa (UCOR) in 1976 and later joined the engineering faculty of the North-West University as professor in mechanical engineering.

He later became Director of the School of Mechanical and Material Engineering and in 1998 he was appointed Dean of the Faculty of Engineering at the North-West University. He was awarded the first chair in nuclear engineering in South Africa and in 2005 he was appointed director of the newly established Postgraduate School of Nuclear Science and Engineering (PGSNSE) at the North-West University.

He has extensive lecturing experience and has inter alia lectured the following university courses: thermodynamics, fluid dynamics, air conditioning, heat transfer, gas dynamics, turbo machines, computational fluid dynamics, thermal-fluid systems design and High-Temperature Reactor (HTR) thermal-fluid analysis.

He has published more than 60 papers in international journals and conference proceedings, co-authored a chapter in a textbook on heat pump design and optimization and has served as study leader for about 20 post-graduate students. 

He was rated by the National Research Foundation (NRF) as an internationally acclaimed researcher - that is a researcher who enjoys considerable international recognition by their peers for the high quality of their recent research outputs.

In 2005 he won the National Science and Technology Forum’s (NSTF) award for the individual who has made the most outstanding contribution to science, engineering and technology (SET) in South Africa through research and its outputs over the previous five years in any sector or discipline of SET.

He has extensive industrial and business development experience. He co-founded the company M-Tech Industrial (Pty) Ltd in 2001 and spearheaded the development of the thermal-fluid systems simulation code Flownex (www.flownex.com ). He also spearheaded the development of the Enerflow range of heat pumps (www.enerflow.co.za ). He has been a principle technical consultant for the Pebble Bed Modular Reactor (PBMR) and in 2008 he was appointed General Manager: Engineering of Pebble Bed Modular Reactor (Pty) Ltd (PBMR), a state-owned nuclear engineering company with a staff of more than 900 at the time.

He served on various councils, boards and committees during his career. Amongst these are board member of the Nuclear Energy Corporation of South Africa (NECSA) and member of the Standing Advisory Group for Nuclear Energy (SAGNE) of the International Atomic Energy Agency (IAEA).

Gideon is well-equipped for the challenges that the relatively new field of renewable energy brings along. He has travelled widely and has worked and lived in South Africa, the UK, Australia, the USA and Canada.

Jaco Kriek – Executive Director

Jaco started his professional career as an article clerk at KPMG in 1987 and qualified as a Chartered Accountant, where after he joined the Industrial Development Corporation (IDC) in 1992. At the IDC he was appointed as the Executive Vice President (Projects) in 2000 and played a key role in initiating projects, business development and the re-engineering of the IDC approach on projects, specifically related to project finance. This position involved significant stakeholder management and the development of new strategies. In the position of Executive Vice President, Jaco was responsible for all large Agricultural, Mining & Minerals, Infrastructure, Chemicals, Oil and Gas projects.

Jaco served on behalf of the IDC on many boards and has led many project finance teams in large projects.

In February 2004 Jaco was requested by Minister Erwin, then Minister of Trade and Industry, to participate in a Government Task Team, to review the options for the Pebble Bed Modular Reactor Company (PBMR) and assist in negotiations with Areva and specifically the Chairman of Areva, Anne Lauvigane. In May 2004 Jaco was asked to take over as the CEO of PBMR and was initially seconded from IDC. In December 2005 he joined PBMR as a full time employee.

Jaco brings extensive project finance and project development experience to Ennex and is passionate about renewable energy and the future that it holds for Africa.


Jan van Ravenswaay – Executive Director

Jan is an Executive Director at Ennex Developments and is a co-founding member of Ennex Developments. Jan van Ravenswaay has 14 years of experience in the engineering field, mainly focusing on energy and water related projects and technology development. He started his career in the power generation sector at Eskom’s Matimba Power Station where his responsibilities as process engineer included plant optimization and performance enhancement, unit trip root cause investigations; plant commissioning, optimization and start-up as well as RCMII analysis.

In 2000 he joined M-Tech Industrial, a specialized engineering consulting firm as an engineering consultant. His involvement with M-Tech provided him with exposure to the thermal hydraulic analysis and simulation that included the development of specialized thermal hydraulic software as well as the associated verification and validation thereof. As consultant for M-Tech he was also involved in project development and high level design process of High Temperature Gas Reactor (HTGR) systems (mostly for process heat applications). He was also involved in technology development as well as to the design, development and operation of test facilities for HTGR system and component demonstration and characterization.

During his career at M-Tech he held executive positions as Business Development Executive and COO. Key experience includes project development and management, system(s) integration and optimization, technology development and thermal hydraulic modeling and simulation. He also works closely with North-West University on new technology development projects such as hydrogen production through thermo-chemical water splitting, thermal desalination, and concentrating solar thermal energy for power and process heat applications.

Jan brings extensive power generation experience to Ennex and is a truly capable driver of new technology development and execution of projects.