System Modeling and Thermo-Economic Analysis of a High Concentration Photovoltaic Thermal System

Solar energy is a free and abundant renewable energy source which is expected to contribute towards reducing the environmental impact of worldwide electricity production. However, the harvesting of solar energy is associated to investment costs. Industry therefore drives the development of low-cost photovoltaic installa- tions which have mostly low efficiency and thus require large area deployment. As a consequence the albedo of the Earth’s surface is reduced which has a negative impact on global warming. The latter externality illustrates the necessity of high efficiency solar energy conversion. This study focuses on a High Concentration Photovoltaic Thermal (HCPVT) system approach which promises high efficiency solar energy conversion into electricity (25%) and heat (55%) at low manufacturing costs. Sys- tem modeling and a thermo-economic analysis is performed to study the energetic and cost performance of the system. It is demonstrated that the system has quick dynamic response to sunlight and short heat-up intervals. The heat is extracted at a high temperature level (85◦C) and can be utilized subsequently for covering residential cooling and heating demand (trigen- eration). For the case of Phoenix, AZ, U.S., it is determined that the levelized cost of electricity is close to the current retail electricity prices. This is a very encourag- ing result, taking into account the early stage of development of the system and the associated uncertainty in cost estimates. Large-scale deployment and commercial- ization of the technology is expected to additionally promote the system’s economic competitiveness due to economies of scale and their associated cost reductions, as been the case throughout the history of the solar and semiconductor industries.