General information Location: SBIC East Head Office Building. PV Field Test, Tokyo, Japan Sunshine hours (yearly average): 4,96 hours per day Type of project: Commercial Type of application: BIPV Time for design process: Schematic: 3 months Final drawings: 3 months Construction documents: 6 months Time for construction: Construction started January 1997, completion April 1998. Realization: April 1998 [ Top ] Description In the original plan, introduction of BIPV was not considered. However, effective adoption of vertical louvers was considered in order to decrease the air conditioning load during afternoon sun. Though the building is surrounded by the newly developed city centre area of Shibuya, the sunshine condition is relatively good because the railway area of the Yamanote line runs along the west side of the site. Therefore, both estimation of annual power generation and conceptual system design were performed based on the results of studying the shadow condition, and the adoption of BIPV was finally decided as an integration element of the outside building design. As I used to be on the committee of NEDO, conducted R&D of BIPV, and had wanted to design PV buildings, I made a proposal to the owner, a related company of METI. After receiving the approval of the owner, the design work started.Environment-friendly buildings are now one of the most important considerations for every company, and SBIC East Inc. decided to adopt BIPV for the outside design with venture capital to help promote small & medium businesses. Awareness among architects is important for the introduction of BIPV. [ Top ] System characteristics PV system power: 30,5 kWp (dummy cell is 985 W). Type of building integration: Eave type semi-transparent array (0,9 kWp, dummy cell cap. is 240W) Inclined type module (5,1 kWp, dummy cell is none) Furring type module (4,4 kWp, dummy cell is none) Shade louvre type semi-transparent module (20,1 kWp,dummy cell capacity is 745 W) Type of cell technology: Mono crystalline silicon (Eave type semi-transparent module, Shade louver type semi-transparent module) Grey coloured Poly crystalline silicon (Furring type module) Poly crystalline silicon (Inclined type module) Module dimensions: Eave type module (480x1528x14mm),15 modules Inclined type module (530x1200x35mm), 60 modules Furring type module (190x1750x23mm), 160 modules Shade louvre type (480x1825x14mm), 240 modules Inverter: Capacity 30 kW (Nisshin Denki Ltd.,Co.) [ Top ] Project cost breakdown Total cost of SBIC East bldg.: 3 300 million yen (€ 30 363 000) Total cost of Field Test of Solar Energy Plant: 139 million yen (€ 1 279 000) Solar modules: 59 million yen (€ 542 900) Other electrical components: 13 million yen (€ 119 600) Installation costs: 57 million yen (€ 524 500) Maintenance, monitoring & others (5 years): 10 million yen (€ 92 000) [ Top ] Performance characteristics The SBIC East Bldg. was reported in building magazines as Japan's first case of total introduction of BIPV in the building design. Many visitors flocked to see this key BIPV building, and it was used as the location for a TV drama. The building is reported to be helping the hiring of outstanding new employees. Benefits have been great for SBIC East Inc., which promotes advanced small & medium companies and venture businesses, as an owner of an environment-friendly sophisticated building. As 30-kW inverters were installed for four 30-kW power generation arrays in total, the conversion efficiency sometimes decreases during operation, so the use of smaller capacity inverters should have been considered. The SBIC East Bldg. system has operated well since Apr. 1998. The system have provided 30 400 kWh electricity during thirty months from April 1998 to December 2000, and the average of system availability was 4,9%. In 2000, the final PV system yield, i.e. electricity per PV capacity, was 421 kWh/kW. This value is less than half of typical value of the final PV system yield for Japanese Field Test Program’s PV systems, 1000 kWh/kW. Power conditioning efficiency varied between about 70% and 90%, and the average of the power conditioning efficiency was 82%. Performance ratio of the system varied between about 40% and 60%, and the average of the performance ratio was 53%, which was about 20% less than annual average performance ratio of sampled 150 Japanese Field Test Program’s PV systems in 1998(1). Because of lower reliability of its own irradiation data caused by frequent shadow on its pyranometers, irradiation data measured by Japanese Meteorological Agency at Tokyo weather station, which is six kilometers from the system, were used as alternative irradiation data for estimating the performance ratio. The condition of irradiation measurement at the weather station is better in sky factor than one at general urban area, therefore substituted irradiation could be slightly larger than actual irradiation on the PV arrays, and cause to decrease performance ratio estimates. Electricity generated: 7151 kWh from April 1999 to September 1999 and 5387 kWh from July 2000 to December 2000 System availability: 36,1 % and 4,5 % respectively Incidents or Outages: 16 (days) in period July 2000 - December 2000 Cause: unknown [ Top ] Project team Client: Tokyo Small and Medium Business Investment Consultation Company (SBIC) SBIC Bldg.,3-29-22,Shibuya,Shibuya-ku,Tokyo 150-0002 Tel: +81 3 5469 1811 Fax:+81 3 5469 5875 Project architects: NIHON SEKKEI, INC. 29th Floor, Shinjuku I-Land Tower, 6-5-1, Nishi-shinjuku, Shinjuju-ku, Tokyo, 163-1329 Japan http://www.nihonsekkei.co.jp/ Design: Jiro Ohno, Architect Senior Manager, Architectural Design Div. NIHON SEKKEI, INC. Tel.: +81 3 5325 8794 Fax: +81 3 5325 8821 Email: oono-j@nihonsekkei.co.jp General Contractor: Nippon Steel Corporation http://www.nsc.co.jp/ Sub Contractor: Nishin Electric Company Ltd,. PV manufacturers: YKK ARCHTECTURAL PRODUCTS INC http://www.ykkap.co.jp/top.html ATLANTIS [ Top ]