In this blog post, Barbara Orlandi, project engineer at MWH (Italy) and winner of the Best Paper Awards 2011 for Renewable Energy World Europe explores the main technical, contractual and economic aspects of developing large-scale PV plants.
Italy’s Conto Energia photovoltaic (PV) support scheme has driven significant market development, but there are many aspects to consider when installing a PV plant. These include technical feasibility, production estimates and authorization issues, as well as profitability and supporting commercial contracts.
The main component of a PV plant is the PV module, which has a big impact on the plant investment cost due to a direct proportionality between efficiency and price. Plants are dimensioned and designed according to the panels’ nominal power, but the plant’s actual performance will be determined by the panels’ real output: the flash test peak power.
Performance of a PV plant is also determined by the system integration. The dimensioning, selection and position of the inverters used to convert DC to AC power should also be designed carefully.
Since large-scale PV plants are typically developed under a project financing scheme, payments occur at milestones set within the EPC contract and are split among project phases. The trend is to pay 10-15 per cent at the signing of the contract, 65-80 per cent proportional to the work progress and to leave 10-15 per cent at the Provisional Acceptance Certificate (PAC), which is released after the Provisional Acceptance Test (PAT) execution.
In order to be successful, large-scale PV plants must identify the optimum balance between technology and economics. This optimisation has to be applied throughout the project from the design phase to plant construction and commissioning. Several factors will impair plant performance, including design choices, optimal implementation of the designed solutions and the proper ‘tuning’ of the plant in the first years of operation.
At this year’s Renewable Energy World Europe delegates will have the chance to attend sessions addressing ‘The Race for Solar Success’ and ‘Solar at Scale’. For a full list of the conference tracks and sessions please visit the pre-show guide.