General information Location: Zurich, Switzerland Sunshine hours (yearly average): 3,6 hours per day Type of project: Sloped roof integration, SOLRIF system Type of application: Retrofit Time for design process: 2 months (incl. electrical engineering) Time for construction: 2 * 2 weeks Realization: - [ Top ] Description Within the frame of the Solarstock exchange by the power utility of Zurich, a large PV power plant was integrated into the roofs of two apartment houses, using the SOLRIF system. In total 624 BP Solarex 585, framed with the SOLRIF system were installed onto 410 m2 roof. Resulting in a total capacity of 53,04 kWp installed power. The houses are built with standard clay tile sloped roofs. On the part of the roof, that was covered by the PV laminates, all the tiles were removed. In such a way the installation gave the impression of a picture with a frame. The system should be easy to mount (less construction work), in combination with the existing clay tiles usable and a good appearance should result. The goal was also to built a cost effective BIPV installation, the power utility of Zurich accepts offer for solar energy of less than 0,70 USD/kWh for their Solarstock exchange, and a perfect appearance, due to the location and the usage of the buildings itself. The PV power plant was integrated into the roofs of two apartment house rows, using the SOLRIF system. In total 624 BP Solarex 585, framed with the SOLRIF system were installed onto 410 m2 roof. Resulting in a total capacity of 53,04 kWp installed power. Maximum available roof area was 660 m2. The roofs are covered with standard clay tile sloped roofs. The system should be easy to mount (less construction work), in combination with the existing clay tiles usable and a good appearance should result. SOLRIF is a new photovoltaic integration system for inclined roofs. This system is suitable for almost any type of inclined roofs in existing or new buildings and meets high esthetical demands too. SOLRIF considers economical, ecological and functional aspects known at the present time. The unit consists of any type of solar laminate and four specially designed aluminium profiles for framing it. As an option, the profiles are available in any colour for optimal matching to the surroundings and the laminate. PV modules framed with SOLRIF provide watertight roofing comparable to standard clay tiles. SOLRIF modules replace the conventional roof covering with clay tiles, shingles or other materials. [ Top ] System characteristics PV system power: 53,04 kW Type of building integration: Sloped roof Type of cell technology: Mono crystalline Module dimensions: 520 * 1118 mm Array dimensions: 2*66.3m2, 2*63.5m2 and 2*77.4m2, in total 410m2 Inverters: String inverters 2 500 watts (18) and 4 000 watts (2), Manufacturer: ASP Top Class (Swiss Manufacturer) BOS components: SOLRIF Integration frame system [ Top ] Project cost breakdown Solar modules: € 261 120 Inverters: € 54 600 SOLRIF Frame, Mounting system: € 31 130 Roof work, Construction: € 19 840 Electro installation: € 48 800 Engineering, Design: € 32 320 Miscellaneous: € 16 880 Total: € 464 690 [ Top ] Performance characteristics A total power production of 43 300 kWh per year was calculated. The inverters and the modules work well so far, meeting the expectations for the first year operation. The building performance has not being change by the new applied SOLRIF roof integration system. Weighted with the actual weather data the Meteonorm base was multiplied and resulted in the predicated figures for the year 2000. Shown are the monthly predicted values (in total 44 143 kWh) versus actual performance data (in total 46 182 kWh). The performance is approx. 5% better than predicted and gives savings of about 22t equivalent greenhouse emissions (CO2) in the year 2000. This is resulting because of no incidents during the year, less snow on the modules then expected and a perfect inverter performance with an annual efficiency of approx. 92%. The performance ratio could not be calculated, because no pyranometer was installed on the roof. The owner dismissed an extensive monitoring program and demanded a monthly comparison of the predicted values versus the actual performance. Electricity generated: The installation has been operating since 7 August 1999. From 1 November 1999 to 31 October 2000 it produced 43 000 kWh, which is close to 810 kWh / kWp. System availability: Almost 100 %, some losses (approx. 2%) due to snow covering (total area) on the modules. February 2000 was a rough month with exceptional big snow falls. Incidents or Outages: 0 All 20 inverters are operating perfectly. Both installation (2 * 26.52 kWp on two house rows) are being checked monthly. The energy production is compared to the forecast monthly figures. If any incident happens, an alarm lamp signals at the entrance that the residents of the building have to contact the responsible person. During a test phase it was noted that almost all residents are actively involved in the monitoring of the PV installation, and also like to be. [ Top ] Project team Client: ABZ, Allgemeine Baugenossenschaft Zurich Project architects: Enecolo AG Engineers: Enecolo AG PV installation: Energieprojekte Kottmann Structural support for PV: Ernst Schweizer AG PV manufacture: BP Solarex [ Top ]