1. Centre for Solar Energy Research, Glyndŵr University, OpTIC, Ffordd William Morgan, St. Asaph Business Park, North Wales LL17 0JD, UK
2. M-Solv Ltd, Oxonian Park, Langford Locks, Oxford OX5 1FP, UK
3. School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh Campus, Edinburgh EH14 1AS, UK