- Title: 'Photovoltaic System Design for a Contaminated Area in Falun - Comparison of South and East-West Layout'
- Author: Anton Fedorov
- Supervisors: Frank Fiedler
- Context: Dalarna University on request of Falu Energu & Vatten
- Status: Submitted and passed. Pending of Publication.
The main aim of the work was to design a photovoltaic plant to optimally cover a piece of urban land previously polluted by an acid factory; then to find the most financially attractive combination of used components and system layout. In this thesis the solar part of a large grid-connected photovoltaic system design has been done. The main purpose was to size and optimize the system and to present figures helping to evaluate the prospective project rationality, which can potentially be constructed on a contaminated area in Falun. The methodology consisted in PV market study and component selection, site analysis and defining suitable area for solar installation; and system configuration optimization based on PVsyst software simulations and Levelized Cost of Energy calculations.
The procedure was mainly divided on two parts, preliminary and detailed sizing. In the first part the objective was complex, which included the investigation of the most profitable component combination and system optimization due to tilt and row distance. It was done by simulating systems with different components and orientations, which were sized for the same 100kW inverter in order to make a fair comparison. For each simulated result a simplified LCOE calculation procedure was applied. The main results of this part show that with the price of 0.43 €/Wp thin-film modules were the most cost effective solution for the case with a great advantage over crystalline type in terms of financial attractiveness. From the results of the preliminary study it was possible to select the optimal system configuration, which was used in the detailed sizing as a starting point. In this part the PVsyst simulations were run, which included full scale system design considering near shadings created by factory buildings. Additionally, more complex procedure of LCOE calculation has been used here considered insurances, maintenance, time value of money and possible cost reduction due to the system size.
Two system options were proposed in final results; both cover the same area of 66000 m2. The first one represents an ordinary South faced design with 1.1 MW nominal power, which was optimized for the highest performance. According to PVsyst simulations, this system should produce 1108 MWh/year with the initial investment of 835,000 € and 0.056 €/kWh LCOE. The second option has an alternative East-West orientation, which allows to cover 80% of occupied ground and consequently have 6.6 MW PV nominal power. The system produces 5388 MWh/year costs about 4500,000 € and delivers electricity with the same price of 0.056 €/kWh. Even though the EW solution has 20% lower specific energy production, it benefits mainly from lower relative costs for inverters, mounting and annual maintenance expenses.
When it comes to electricity production profile, it turned out that there is no optimal orientation and every PV setup has its pros and cons. The East-West system has better daily profile with lower midday peak and higher performance in mornings and evenings. On the other hand, the South option gains relatively more energy during cold seasons, when the demand is higher and the electricity in Sweden is more expensive. However, for the case the EW system can have a considerable privilege. As the studied territory is highly contaminated, it can allow collecting up to 80% of rain water on the area occupied by the plant. South orientation can collect just 13% in contrast. Additionally, the East-West is a relatively new concept of PV design, which can result in better advertising effect for the project and will be a good subject for further research and development.
It is interesting to mention that after the defense presentation Falu Energi & Vatten showed a great interest to the East-West design. According to the company statement, the idea of water amount reduction, which goes into the polluted soil can be the key factor allowing the plant to be actually realized. And if the project goes through to construction, it will represent the largest photovoltaic system in Sweden up to date.