The team behind STG consists of a core group of MIT-trained engineers and experienced business and development experts, joined by a group of dedicated students, industry consultants and advisors with experience in renewable energy and developing world markets. A team of talented engineers in Lesotho continues to bring STG’s vision to life on the ground through training programs, educational initiatives, and field prototypes.

Matthew Orosz, PhD


Matt is the Lead Engineer and Project Coordinator for all of STG’s projects in Lesotho, the visionary behind our new minigrid design thrust, and continues to provide inspiration and leadership to the group. Matt recently completed his tenure as an Echoing Green Fellow (2012-14), in addition to previous terms as a Switzer Environmental Fellow and a Fulbright Scholar.  Matt holds his doctorate in Civil and Environmental Engineering (MIT ’12), an M.Sc. in Technology and Policy (MIT ’06), an M.Eng. in Civil and Environmental Engineering (MIT ’03), and a B.A. in Environmental Science (Dartmouth ’00).

Amy Mueller, PhD


Amy’s technical work focuses on the electrical and electronic control systems, including sensor design and data acquisition; she has contributed to work in Lesotho since 2005 and to the development of the Eckerd field site system since its inception.  In addition to her role as Treasurer, Amy also acts as the Technology Liaison for STG.  Amy holds a doctorate in Environmental Chemistry (MIT ’12), and an M.Eng. (MIT ’03) & S.B. (MIT ’02) in Computer Science and Electrical Engineering.

Bryan Urban


Bryan designed and led STG’s first market, customer, and government study for Lesotho in 2007 and continues to provide insight into project, partner and market development in his role as Director.  Bryan has extensive expertise in heat transfer modeling, business development, and entrepreneurship and holds two degrees in Mechanical Engineering (S.M. MIT ’07, B.S. Cornell ’04)

Hugh Molotsi


Hugh Molotsi joined STG as an Advisor in 2015, bringing with him both entrepreneurial expertise and passion for grassroots innovation. Hugh recently concluded a 22-year career at Intuit where his last position was Engineering Fellow and Vice President; during his tenure, Hugh was a serial innovator who helped launch several new businesses including Intuit Payments. Hugh is also on the advisory board of #YesWeCode and past president of the Board of Directors of Fresh Lifelines for Youth. Hugh holds a M.S. in Computer Engineering from Santa Clara University and a B.S. in Computer Engineering Technology from the University of Southern Mississippi.

Sylvain Quoilin, PhD

Sylvain holds a doctorate from the University of Liege, and joined STG in 2008 as a research scientist specializing on design and modeling of small scale ORC technology. Sylvain’s role on STG’s team is ORC system improvements, modeling, and advanced technology development, along with contributing to work testing pilot systems deployed in Lesotho.

Lengeta Mabea

Mr. Mabea is the Senior Renewable Energy Engineer at the Appropriate Technology Services (Government of Lesotho) and since 2007 has been the acting liaison between STG International and this key partner organization. In addition to helping oversee STG-sponsored work while the USA-based team is not in Lesotho, Mr. Mabea brings an important perspective to the project which balances novel engineering work against the practical constraints of working in a developing country context. Mr. Mabea holds dual bachelors degrees in Mechanical Engineering (’01, University of Natal, South Africa) and Physics & Maths (’95, National University of Lesotho).

Kopano Tsenoli

Since 2009, Mr. Tsenoli has been the Chief Engineer at the Appropriate Technology Services (Government of Lesotho) and a strong supporter of STG’s work in Lesotho through this ongoing partnership. Mr. Tsenoli has expertise in engineering and project management, overseeing work as diverse as renewable energy, efficient cookstoves, solar fruit dryers, and courses designed to transfer manufacturing and usage expertise to individuals throughout Lesotho.

Makoanyane Khakanyo

Makoanyane is the key individual in charge of system maintenance at Pilot Clinic in Lesotho. He has worked with the STG-USA team on the construction of the solar systems since November 2006, concurrently working toward a B.Tech. in Mechanical Engineering at the Central University of Technology (Bloemfontein, South Africa). Before working with STG, Makoanyane studied mechanical systems and Fitting and Machining at Lerotholi Polytechnic (Lesotho).

Marcel Ntee

Marcel joined the STG team in Lesotho as an Assistant Technician in May 2015 after three months of interning with our team. Marcel has a B.S. in Mechanical Engineering from the Camilo Cienfuegos University of Matanzas, Cuba (2014), which he is putting to great use helping design and build out the equipment for our new solar manufacturing line.


Elizabeth Wayman

Libby has extensive experience in thermodynamics and renewable energy systems and contributed significantly to STG’s early R&D through thermodynamic modeling and construction of the heat engine. She was also a key part of the vision and direction of the organization in a management/advisory capacity from its inception in 2006 until 2012 when she stepped down from the Board of Directors to pursue an opportunity with the U.S. Department of Energy. Libby holds an M.Sc. in Mechanical Engineering (MIT ’06) and an S.B. in Civil and Environmental Engineering (MIT ’04).

Motlatsi Sekhesa

Motlatsi was the lead engineer and key entrepreneur promoting STG-type solar energy work in Lesotho from 2006-2008; Motlatsi has started his own general purpose engineering company in Lesotho, running the country’s only fully-equipped machine shop! Motlatsi has a Diploma in Mechanical Engineering from the Cape Peninsula University of Technology (’07) and a Certificate in Fitting and Machining from Lerotholi Polytechnic (’98).

Tumelo Makhetha

Tumelo was a key contributer in the design and construction of the mechanical trough prototypes from 2006-2009 and led a team of technicians during site preparation and installation at Pilot Health Clinic.  Tumelo currently holds an engineering management position at Maluti Brick.  Tumelo has a B.Tech. from the University of Johannesburg (’07), and he recently earned his Bachelor’s Degree (’09) at the Tshwane University Of Technology in Pretoria, South Africa.

Tamer Teker

Tamer has been working with STG since summer 2014 on a wide range of engineering projects, looking at topics as diverse as collection of energy use data and engineering design for new solar hardware. Tamer is currently acting as Team Leader and Project Manager in Lesotho, overseeing the design for manufacturing process on our new solar collectors and growing collaborations across governmental, public, and private sectors.

Lefu Maqelepo

Lefu is currently pursuing a degree in Mechanical Engineering at the University of Botswana and chose to come back to Lesotho to complete his required Practicals (internship component of his degree) with STG this year. Lefu will be with STG from January through June 2015, working on solar trough design and energy monitoring system installation.