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Turning apartment rooftops into 'virtual power plants', green energy through mega-solar power generation

Leopalace21 Corporation

We have been able to make a significant contribution toward creating a green society by engaging in a verification project together with Fujitsu and implementing ICT infrastructure to remotely monitor installations dotted throughout the country.

Shigeru Ashida, General Manager of Business Plan Director, Executive Director, Leopalace21 Corporation

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Leopalace21 has launched an innovative business by installing photovoltaic (PV) solar panel systems on apartment rooftops throughout Japan to operate as utility-scale virtual power plants. The company has adopted Fujitsu's Venus Solar as the ICT infrastructure solution for its operations management and maintenance needs, remotely monitoring the minute-by-minute operational status of systems distributed across 4,500 apartment buildings. This has enhanced the efficiency of its mega-solar operations by identifying the cause of any drop in output, thereby ensuring that every opportunity to generate power is harnessed.

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Contributing to society through virtual mega-solar power plants on apartment rooftops

Leopalace21 Corporation is a major real estate leasing firm. The company approaches landowners with proposals for effective land usage, undertakes the construction of condominiums or apartment blocks on that land, then bulk-leases and manages each building after completion. Leopalace21 is also engaged in the business of leasing individual apartments to tenants throughout Japan. The company has recently begun to actively pursue opportunities overseas, establishing local offices in Southeast Asia – including Thailand, Vietnam, and the Philippines – to provide real estate brokerage services.

With the aim of boosting its contribution to society, Leopalace21 is focusing on energy projects, one of which is the virtual mega-solar project known as Roof Mega-solar Project. This involves using the rooftops of its leased apartments as 'power plants' to harvest solar power as a source of eco-friendly renewable energy. As of September 2015, the company had installed PV systems on the rooftops of 4,500 apartment buildings, with a total generating capacity of 70 Megawatts.

A chance encounter with a Fujitsu employee overcomes challenges and leads to new business

Roof Mega-solar Project reached the point where it could generate enough eco-friendly solar power to meet the annual needs of more than 18,000 typical households. But installing PV systems was not as attractive to apartment owners as the company had hoped. Some owners were already receiving stable rental income and were not necessarily keen to invest extra funds for the installation of power generating facilities.

Furthermore, even with the consent of apartment owners, no substantial operation and maintenance service existed to cater for small-to-medium scale apartment rooftop installations (unlike for single-family detached houses and utility-scale solar projects).

The solution came from a chance encounter. Shigeru Ashida, Executive Director, Leopalace21 Corporation recounts, "The breakthrough came when a Fujitsu employee who happened to be living in an apartment managed by our company devised the 'roof-lease' idea, which entails leasing roof space from apartment owners in order to generate power."

Remotely monitoring installations throughout Japan by applying cutting-edge ICT

Monitoring power generation

All of the power generated from apartment rooftops is sold to major power utilities at a fixed-price, and some of this income is paid to apartment owners for renting their rooftop space. This means that apartment owners can actually earn extra income without having to bear the upfront investment costs. In addition, the cooperation of many apartment owners promotes the deployment of renewable energy, bringing us a step closer to creating a green society.

The business model jointly developed by Leopalace21 and Fujitsu was launched as a pilot project in Fukushima Prefecture; September 2012 saw verification start at 70 apartments in that prefecture. The project helped staff acquire expertise in using ICT to bring together small-tomedium scale PV systems installed on physically disparate apartment rooftops and run them as a virtual mega-solar power generation system. At the same time, the project confirmed that the "roof-lease" model is conducive to reducing the environmental footprint.

Building on these results, Leopalace21 launched its Roof Mega-solar Project business nationwide. The group company established to drive this initiative has so far installed 4,500 PV systems over three years. It has increased year-on-year the amount of power generated and sold.

Fujitsu provides infrastructure support for the project. The PV remote monitoring solution known as "Venus Solar" was developed by Fujitsu based on its understanding of Leopalace21's needs, the know-how accumulated through many years of remote monitoring and control of plants and buildings, and the knowledge acquired through the Fukushima Prefecture Pilot Project for Virtual Solar Power Plant. Each apartment complex has four or five power conditioners for PV power generation, and the power output by each is collected at one-minute intervals for monitoring at a datacenter.

Mr. Ashida, explains that via remote monitoring, "We are now able to accurately monitor the status of facilities throughout Japan from the datacenter and we can see whether any drop in output is due to changes in weather, shadows cast by surrounding buildings, or technical problems. Because identical equipment is installed on the apartment building rooftops, if there are noticeable differences in the power delivered by each power conditioner, we are able to conclude that it is most likely caused by a technical fault." In describing the results produced by the detailed monitoring service provided by Venus Solar, Mr. Ashida added, "The monitoring service leads to stable business income because it guards against the loss of energy generation opportunities caused by system failures."

Leopalace21 will continue to accelerate its program of initiatives that contribute to society. For example, the company is considering public disclosure of energy production figures from the rooftop mega-solar installations operating at nearly 5,000 locations around the country. This move will allow apartment owners who are considering installing solar PV to gain an accurate understanding of the generating capacity and economic viability of a solar system. Mr. Ashida concludes, "We ask Fujitsu to provide their ongoing support and look forward to further innovative proposals for our next new project."

Customer Profile

Address 2-54-11 Honcho, Nakano-ku, Tokyo, Japan
Founded 1973
Employees 7,765 (as of Dec 31, 2015)
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[ Published in 2016 ]

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