Techno-Economic Analysis of a Commercial Factory’s Renewable Energy System Replacement Alternatives

Renewables typically have a finite life expectancy of around 20 to 30 years. An existing wind energy system for a large commercial factory in the rural area of Barnard Castle, United Kingdom (UK) is nearing the end of its usable life. The existing system is operating at 8 % load factor, providing only 5 % of the site annual load. A techno-economic assessment of three renewable energy proposals will ensure the site’s energy strategy is successful. Three proposals were examined, to continue with the current system until failure, to overhaul the current system and prolong its usable life, or to replace the wind turbines with a rooftop photovoltaic (PV) system. The Net Present Value, Payback Period, Levelised Cost of Electricity and the equivalent Carbon Dioxide emissions were compared for each alternative. The photovoltaic system was the unanimous choice. The Analytical Hierarchy Process was used to systematically select the most appropriate PV module technology for the proposed system, based on the most important factors. Seven different PV module variants were selected and given weighted ratings to determine the most suitable model, the outcome of this was the SunPower SPR-MAX2 360 model. This decision was verified by the Consistency Ratio which indicated an informed decision had been made.