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MPhil in Engineering for Sustainable Development

global challenges, engineering solutions

Studying at Cambridge

Michael Maks Davis

‘Rent your roof!’, a feasibility study to install solar PV arrays onto household roofs, sell the electricity to the grid and share the profit with the homeowner.

Michael Maks Davis

‘Rent your roof!’, a feasibility study to install solar PV arrays onto household roofs, sell the electricity to the grid and share the profit with the homeowner.

The work sets out to assess the feasibility of creating a business plan that foments the installation of photovoltaic (PV) arrays onto household roofs. This research has been carried out in light of the recent changes to the government feed in tariff subsidies, which previously offered a generous rate of return for those seeking to install a PV array. The resources for the work were: the knowledge and experience of peers, the MPhil modules studied and the author’s own research.
The work was divided into three stages. The first was a study of the business models currently being applied in the sector of domestic PV arrays. This was achieved through a focus group with peers on the MPhil course, in addition to conducting interviews with companies and organisations working in the sustainability sector. The second stage consisted of an analytical hierarchal process (AHP), aiming to determine what PV technology is optimal for hot & dry Vs. temperate climates. AHP is a form of decision-making that establishes priority options using a mathematical procedure, and where in this case the goal was ‘Choosing the most appropriate PV technology’. The calculations were carried out from first principles, which had been learnt during the MPhil module studies and meant a more robust mathematical model could be created. The criteria for the AHP analysis were: cost, yield, durability and industrial ecology. The options for the PV technologies being assessed consisted of those that are currently available on the market, ranging from crystalline silicon modules through to dye sensitised solar cells. Third, fieldwork research was carried out in order to determine what people’s views actually are regarding getting a PV array installed on their household roof. The research was conducted in two villages. The first was Sandford in Devon, UK and the second Navaluenga in the region of Avila, Spain. The fieldwork was a qualitative sociological study that consisted of over thirty semi-structured interviews. This technique allowed for the people being interviewed to express their views in a manner that would not have been possible in a rigid questionnaire.
Overall, from the first stage of research it was found that there were numerous business models currently being applied in the PV sector. These ranged from the homeowner purchasing a PV array outright, to a community cooperative being set up to foment PV array installations. In the second stage, little difference was found in the AHP as to whether the PV technology was installed in a hot & dry or temperate climate. On the other hand however, the AHP showed that the time may be ripe to move away from traditional crystalline silicon modules to other thin film technologies. Finally, the third stage of the work found that regardless of the household type or country, one of the main concerns of household members are the high costs and long payback time associated with installing a PV array.
The final step of the thesis is to bring the three stages of work together in a robust business plan for the fomentation PV arrays onto household rooftops.