Abstract: This is the first special section by IET-Renewable Power Generation on this conference series. PVSAT was established in 2003 to serve the needs of the UK as well as international community for a focal point of materials and applied research in photovoltaics in a manageable size conference without parallel sessions. The concept of a residential conference has been very successful and since 2007 (PVSAT-3) this is an annual event with in excess of 60 papers and 100 researchers participating. In 2013 PVSAT has teamed up with IET-RPG to publish a special edition of the engineering related papers of this conference. 2012 has proved a very challenging year for the global PV community with oversupply of product driving down prices and profitability in the PV market. Nevertheless the market has grown and new research challenges have emerged. Priority items are developing the new PV technologies to take cost below €0.4/Wp, developing storage systems at the domestic and multi-megawatt level and how to predict control and monitor PV performance to allow grid penetration of PV generation to well above 10%. The UK situation has been somewhat different to the world market as the installations in the UK have grown rapidly from a cumulative installation around 750MWp in December 2011 to nearly 1.4 MWp in December 2012. This has been one of the highest growth rates in the world despite the global problems in the PV industry. The papers in this special section were selected from about 30 engineering based papers within the PVSAT-9 conference based on their scores in the paper evaluation by the referees. Four of the highest ranking papers were extended for publication in IET-RPG and underwent rigorous refereeing as with all other publications in this journal. The papers published here cover a very wide range of engineering related subjects relevant to photovoltaics. They range from potentially new application of photovoltaics (Diyaf et al ‘Contacts on polyester textile as flexible substrate for solar cells’) to the cost of energy generation (Georgitsioti et al ‘The simplified levelised cost of the domestic PV energy in the UK: The Importance of the Feed-in Tariff Scheme’). Two further papers cover the understanding of PV module behaviour (Wu et al ‘A distributed electrical network modelling approach for spatially-resolved characterisation of photovoltaic modules’) and a novel characterisation method for photovoltaic modules (Sara et al ‘Determining spectral response of a photovoltaic device using polychromatic filters’). Together these papers provide a significant view of the currents status of engineering issues in the UK photovoltaics market. Ralph Gottschalg (PVSAT Conference Secretary), Head of Energy Division & Applied Photovoltaics Research Group, Centre for Renewable Energy Systems Technology, School of Electronic Electrical and Systems Engineering, Loughborough University, UK. Dr Tim Bruton (PVSAT Conference Chair), PV Consultant, Woking, UK.