Our Team Meet the engineers behind Greenplan

Josebus Van Zyl

Director, Computational Fluid Dynamics

Sewis Van Zyl is responsible, amongst others, for general building performance modelling at Greenplan Consultants. With 15 years of experience in Computational Fluid Dynamics (CFD), he has a deep passion for combining the art and science of developing effective CFD solutions for complex natural ventilation and wind flow problems. Sewis holds a Ph.D. in Mechanical Engineering from the University of Stellenbosch. Prior to Greenplan Consultants, Sewis did post-doctoral work at both the University of Stellenbosch and National Renewable Energy Laboratory in the USA.

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Kenneth Allen

Director, Thermo-Fluid Dynamics

Kenny Allen is responsible for, amongst other tasks, general building performance modelling. He enjoys the field of Thermo-Fluid Dynamics, and the related topics of power generation and renewable energy systems and technologies. He spent eight years doing research on thermal storage, with a focus on packed beds. Kenny holds an MSc(Eng) and a Ph.D. from the University of Stellenbosch and has also completed post-doctoral research at the same university.

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Bryony Pienaar

Registered Professional Engineer (Pr. Eng.)

Bryony Pienaar has over 12 years’ experience in mechanical engineering, mostly in the manufacturing and minerals processing industry. Her experience includes pump and pipeline system design and materials handling, as well as product development and experimental work. She has been a consulting mechanical engineer for various projects worldwide, with oversight of the mechanical design, construction and commissioning work. She is passionate about engineering and seeks to deliver quality work. She is a professional engineer (Pr. Eng.) and holds a B. Eng. (Mechanical) and B. Eng. Hons. (Technology Management) from the University of Pretoria. Her interests are broad and range from scuba diving and travelling the world to cheese fondue or reading in the comfort of her armchair.

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Sven Oxtoby

Building Performance Assessment, DesignBuilder Sales & Support

Sven conducts SANS 10400-XA rational energy assessments, DesignBuilder Software sales and first-line support amongst other duties. Prior to joining Greenplan Consultants, he worked as a mechanical consulting engineer at WSP on HVAC systems and previously specialised in building performance modelling. Sven holds a BSc in Mechanical Engineering from the University of Cape Town.

Francois Joubert

Founder (In Memoriam)

Francois founded Greenplan Consultants in 2007 after realising the huge impact buildings have on energy and building material resources. He was a passionate champion for the use of building performance simulation to aid designers and developers to create better buildings. He held an M-Eng. in Aeronautical Engineering from the University of Stellenbosch and was a registered professional engineer. He is missed.


"I'm completely blown away by the standards to which you and your team are being industry leaders locally and the level of competency and professionalism to which you all work; it's quite inspiring and respectful to tell the truth and has left me motivated to raise my own game where I can. I have nothing but respect for each of you and the level of professionalism and ethics to which you hold yourselves personally and through your work."

Dennis Guichard DGA Energy

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