Manufacturing of sustainable solar cells

This PhD project investigates the various fabrication and manufacturing techniques used for the production of thin film, second generation photovoltaics (PV) like CdTe (Cadmium telluride) CIGS (Copper indium gallium sulphide) or CZTS (Copper zinc tin sulphide).
The sustainability of each process will be evaluated using a Life Cycle Assessment (LCA) software called SimaPro which will provide data based on the environmental impact of different processes. These environmental impacts can range from human toxicity to global warming potential, ozone layer depletion, acidification, eutrophication, abiotic depletion and more. This allows for comparison between different techniques and materials used.
There are different types of LCA, some are Cradle-to-Gate where the life cycle considered is all stages up to the end of manufacturing (mining, transport, manufacturing), Cradle-to-Grave which also includes the use and disposal of the product, Cradle-to-Cradle which also included the potential impacts of recycling the different parts of the product. It is more uncommon for Cradle-to-Cradle LCA for PV systems due to the insufficient reliable data. Many assumptions also need to be made when conducting an LCA, for example the life-time of the solar panel, the way that materials are transported from their extraction to the manufacturing stage, the percentage of product that is recyclable and more. A sensitivity analysis will be used to compare different methods used to carry out the LCA and validate the accuracy of the results.
To improve the LCA, experiments will be carried out alongside the LCA investigations where the fabrication of a sustainable solar cell can be completed and real data can be collected for use within the SimaPro software. This means a fully functional solar cell can be produced and it allows for the evaluation of the quality of this solar cell that has been created with sustainability as the central focus.
The outcomes of this research have the potential to be applied to other researchers work to show that techniques that they are using can be considered as sustainable. For example, for research which involves the fabrication of solar cells using inkjet printing or the same nanoparticle ink the authors can include parts of this research which describe the environmental impacts of using such materials and processes. With the rapidly increasing capacity and demand for solar power and rapidly decreasing availability for raw resources, sustainability is quickly becoming an important factor in all aspects of research.
The main aim of this project it to use LCA to find, currently, the most sustainable method of producing a functioning thin-film solar cell. This links closely to one of the priorities expressed by the UKRI of engineering net zero and the idea that the findings of this project can be used for a step towards green energy production.
Beyond the single solar cell, work can advance onto looking at the sustainability when these solar cells are integrated into products and buildings and how effective this idea is for the future of PV.

This project is supported by a number of universities and partners in the North East of England as part of the RENU doctorial training programme, primarily Northumbria University, Newcastle University and Durham University as well as collaborations with the Royal Society of Chemistry and the Institute of Physics.

ReNU's enhanced doctoral training programme delivered by three uniquely co-located major UK universities, Northumbria (UNN), Durham (DU) and Newcastle (NU), addresses clear skills needs in small-to-medium scale renewable energy (RE) and sustainable distributed energy (DE). It was co-designed by a range of companies and is supported by a balanced portfolio of 27 industrial partners (e.g. Airbus, Siemens and Shell) of which 12 are small or medium size enterprises (SMEs) (e.g. Enocell, Equiwatt and Power Roll). A further 9 partners include Government, not-for-profit and key network organisations. Together these provide a powerful, direct and integrated pathway to a range of impacts that span whole energy systems.

Industrial partners will interact with ReNU in three main ways: (1) through the Strategic Advisory Board; (2) by providing external input to individual doctoral candidate's projects; and (3) by setting Industrial Challenge Mini-Projects. These interactions will directly benefit companies by enabling them to focus ReNU's training programme on particular needs, allowing transfer of best practice in training and state-of-the-art techniques, solution approaches to R&D challenges and generation of intellectual property. Access to ReNU for new industrial partners that may wish to benefit from ReNU is enabled by the involvement of key networks and organisations such as the North East Automotive Alliance, the Engineering Employer Federation, and Knowledge Transfer Network (Energy).

In addition to industrial partners, ReNU includes Government organisations and not for-profit-organisations. These partners provide pathways to create impact via policy and public engagement. Similarly, significant academic impact will be achieved through collaborations with project partners in Singapore, Canada and China. This impact will result in research excellence disseminated through prestigious academic journals and international conferences to the benefit of the global community working on advanced energy materials.