J. Harvey

A 20-sun hybrid PV-Thermal linear micro-concentrator system for urban rooftop applications

A unique, linear, low-concentration, hybrid ‘micro-concentrator’ (MCT) system concept has been developed specifically for urban rooftop environments. The light-weight, low-profile form factor satisfies aesthetic demands for general rooftop solar technologies, and is a marked departure from conventional linear concentrator systems. Valuable thermal energy, normally of nuisance value only, and usually wasted by conventional CPV, is extracted via a heat transfer fluid. The recovered thermal energy can be used for applications ranging from domestic hot water through to space heating, ventilation, and air conditioning (HVAC), and process heat. The system can be modularly configured for hybrid concentrating PV-Thermal (CPV-T) or thermal-only operation to meet specific customer demands. At a 20x concentration ratio, system output of 500 Wpe and 2 kWpt is expected, for a combined system efficiency of up to 75%. The MCT is constructed from mature, proven technologies and industry-standard processes. An installed system cost of less than US

Results from the first ANU-chromasun CPV-T microconcentrator prototype in Canberra

2/Wpe is targeted, and commercial availability is expected to commence in 2011.

Towards an innovative spectral-splitting hybrid PV-T micro-concentrator

A first prototype of the hybrid CPV-T ANU-Chromasun micro-concentrator (MCT) has been installed at The Australian National University (ANU), Canberra, Australia. The results of electrical and thermal performance of the MCT system, including instantaneous and full-day monitoring, show that the combined efficiency of the system can exceed 70%. Over the span of a day, the average electrical efficiency was 8% and the average thermal efficiency was 60%.

A Monolithic Microconcentrator Receiver For A Hybrid PV‐Thermal System: Preliminary Performance

A hybrid concentrator PV-Thermal (CPV-T) system for delivery of electricity and 150°C hot fluid in a structure suitable for roof-top installation on domestic, commercial, and industrial buildings is being developed by ANU in collaboration with the University of New South Wales, CSIRO, and industry partners. A first design based on beam-splitting utilising liquid-absorption filters is being analysed, with a study of the most suitable candidate fluids. An initial selection of four liquids was conducted; with the liquids subjected to accelerated tests to analyse their long-term performance and possible optical and chemical degradation. Some of the fluids showed optical changes after high temperature test and UV exposure, leading to slight yellowing.

Evaluation Of Electrical And Thermal Performance Of A Linear Hybrid CPV‐T Micro‐Concentrator System

An innovative hybrid PV‐thermal microconcentrator (MCT) system is being jointly developed by Chromasun Inc., San Jose, California, and at the Centre for Sustainable Energy Systems, Australian National University. The MCT aims to develop the small‐scale, roof‐top market for grid‐integrated linear CPV systems. A low profile, small footprint enclosure isolates system components from the environment, relaxing the demands on supporting structures, tracking, and maintenance. Net costs to the consumer are reduced via an active cooling arrangement that provides thermal energy suitable for water and space heating, ventilation, and air conditioning (HVAC) applications. As part of a simplified, low‐cost design, an integrated substrate technology provides electrical interconnection, heat sinking, and mechanical support for the concentrator cells. An existing, high‐efficiency, one‐sun solar cell technology has been modified for this system. This paper presents an overview of the key design features, and preliminary el...

Designing CPV Receivers With Reliability: Early Evaluation of Components

Chromasun Inc. and The Australian National University have developed a low‐concentration, linear, hybrid micro‐concentrator (MCT) system suitable for urban rooftop installation. The system produces both electrical and thermal power, integrating the functionality of separate flat plate photovoltaic and solar hot water systems. The MCT system utilises industry‐standard components, including modified mono‐crystalline silicon one‐sun solar cells, commonly used in flat panel applications. The MCT manufacturing processes are designed around low‐cost methods, and tap directly into existing economies of scale. Initial test results without any system optimisation has demonstrated an electrical output of more than 300 W, and a thermal output of more than 1500 W at 950 W/m2 DNI.

A general purpose characterization system for rooftop hybrid microconcentrators

The Australian National University (ANU) is developing a new hybrid CPV/Thermal micro‐concentrator (MCT) system working at a concentration ratio of 20 to 30X. System design and reliability have been integrated as a concurrent process, enabling early optimisation of the concentrator design. The key feature of this procedure is that a carefully selected set of simple tests can be conducted concurrently with the design of the concentrator module, without introducing time delays on the module design. Test results provide valuable information that significantly informs the design process and helps to avoid future failures.

Hybrid CPV-T micro-concentrator system

A versatile characterization system for hybrid thermal and photovoltaic solar receivers is presented and demonstrated. The characterization of the thermal loss and effective area of a novel hybrid receiver is presented.

Integrating the design and reliability assessment of a hybrid Pv-Thermal microconcentrator system

A hybrid CPV-Thermal (CPV-T) micro-concentrator (MCT) system has been constructed. The MCT is a fully sealed, light-weight structure with a low wind-load factor. It incorporates modified one-sun solar cells operating at around 15 suns optical concentration using a novel ultra-lightweight Fresnel array with closed loop tracking to produce electricity and thermal energy suitable for generating hot water or running absorption chillers. Preliminary electrical and thermal performance data will be presented.

A Closed Loop Tracking System for a Linear Fresnel Hybrid PV/Thermal Microconcentrator System

The Australian National University (ANU) is developing a new hybrid CPV-Thermal micro-concentrator (MCT) system working at a concentration ratio of 20 to 30X. System design and reliability testing have been integrated as concurrent processes, enabling the early optimisation of the concentrator system design. The key feature of this integrated design-test procedure is that carefully selected sets of simple tests can be conducted concurrently with the design of the concentrator module, without introducing time delays in the module design phase. Test results provide valuable information that significantly informs the design process and helps to avoid future failures. The ANU hybrid micro-concentrator receiver also provides heat for domestic applications, introducing special requirements for tests of the active cooling system. IEC 62108 tests procedures have been analysed in order to verify and extend their suitability for active cooling systems. A modified and extended test sequence is proposed to assess actively-cooled CPV and CPV-T systems.