Prof. Christos N. Markides


Next-generation hybrid solar technologies and systems: Challenges and opportunities


Christos Markides is Professor of Clean Energy Technologies, Head of the Clean Energy Processes Laboratory, and leads the Experimental Multiphase Flow Laboratory, which is the largest experimental space of its kind at Imperial College London. He is also, amongst other, Editor-in-Chief of journal Applied Thermal Engineering, a member of the UK National Heat Transfer Committee, on the Scientific Board of the UK Energy Storage SUPERGEN Hub, and is a member of the Assembly of World Conferences (AWC) on Experimental Heat Transfer, Fluid Mechanics and Thermodynamics.

He specializes in applied thermodynamics, fluid flow, heat and mass transfer processes as applied to high-performance devices, technologies and systems for thermal-energy recovery, utilization, conversion or storage. His research interests include heating/cooling provision and power generation, and in particular, solar energy and waste-heat recovery and conversion in diverse applications. He has published >300 journal papers and >350 conference papers on these topics.

He has won multiple awards, including IChemE’s Global Award for “Best Research Project” for his work on hybrid PV-thermal technologies (2018). He also won IMechE’s Donald Julius Groen outstanding paper prize (2016), the Engineers’ Without Borders “Chill Challenge” (2020), as well as Imperial College London President’s Awards for Teaching (2016) and for Research Excellence (2017). His papers are regularly selected for best paper awards at conferences, journal covers or as most cited/downloaded papers in journals, including Best Paper Awards at SDEWES2021, ECOS2020, TFEC2018, ORC2017, Applied Energy’s “Most highly cited original paper” twice (2017&18), a Featured Paper in Light, Science & Applications (2021), and Front-Cover Paper in Nano Materials Science (2021).

Apart from his position at Imperial, he is also Founder and Director of Imperial spin-out company Solar Flow (see:, which is focusing on a high-performance PV-thermal technology for co-generating electricity as well as heat, cooling or clean water.



“Making solar energy economical” is widely recognized as a global engineering grand challenge with the potential to enable the transition to a clean and sustainable energy future. By far the highest global growth and new investment in renewable technologies is being experienced by the solar sector. In fact, solar systems are projected to deliver the majority of the world’s electricity by 2050.

Although most solar technologies today are designed for either electrical power generation (e.g., photovoltaic or PV, and concentrated solar power or CSP) or hot water provision (e.g., solar thermal/hot water systems), solar systems can be used to deliver multiple useful energy vectors simultaneously, including heating, cooling, clean water, or any combination of the above.

In this talk, we will present the underpinning principles of conventional solar technologies, including PV, CSP and solar-thermal, and extend the discussion to more recent options (both collectors and systems), such as hybrid PV-T but also going further to what we will term ‘PV-X’ solar technologies, covering advances from the materials to the system level, discussing their potential, along with the challenges and opportunities of their further development.