Contributing to effective use of resources and reducing CO2 emissions by creating renewable energy in local communities

Local recycling: Large-scale power generation system using waste vegetable oil, creating a local production and consumption resource cycle

[Value provided by Yanmar Group]Local recycling: Large-scale power generation system using waste vegetable oil, creating a local production and consumption resource cycle

Bio-diesel fuels made from waste cooking oil have been used to fuel buses and trucks in some urban areas. However, implementation stalled due to problems during use, resulting from insufficient maintenance. Local governments and companies face issues of treatment and usage related to the disposal of waste cooking oil.

Under such circumstances, Daikou Sangyo, an industrial waste disposal company in Okinawa, has been collecting about 2,500 tons of waste cooking oil per year. This is the equivalent to about one-third of all the oil in the prefecture. It has been shipping SVO to generate FAME, and as boiler fuel and livestock feed.

However, in recent years, demand has become unstable, and in their search for new ways to utilize SVO, the company has been considering redirecting their business towards power generation by selling electricity generated by waste cooking oil they had previously exported. Yanmar took on this challenge together with our customer, in this unknown field, where there was no previous track record in Japan for large engines powered by SVO. Because SVO solidifies at room temperature, it was necessary to switch to Bunker A to start and stop in addition to heating the oil to 60℃ or higher during steady operation.

Yanmar solved this issue by combining the fuel heating device and fuel switching device as a single unit. By completing this system, it became possible to sell the power they generated not only for home use, but also to new power companies. Business revenue stabilized once again and at the same time, it became possible to recycle this renewable energy within Okinawa. Okinawa Electric Power Company has been able to reduce CO2 emissions by 3,060 tons per year as a result of reducing the quantity of Bunker A used in thermal power generation and reducing the amount of fuel used for truck delivery within the prefecture.

What are “SVO” and “FAME” ?

Straight vegetable oil or SVO is crude vegetable oil produced after waste cooking oil has been refined to remove impurities. Although the impact on the environment during production is low, the downsides are that there are issues with quality and high viscosity at room temperature (about 10 times compared with diesel fuel). On the other hand, fatty acid methyl ester (FAME) is produced by a process of transesterification whereby methanol is added to the vegetable oil. While the combustion rate is nearly the same as diesel fuel, the issue with FAME is that it oxidizes easily and corrodes resins and rubbers.

New business model based on large scale power generation system using SVO
Result after implementation of the system

From Our Employees
Gaining customer trust by solving various problems one by one

picture of staff

Kazuo Kato
Technology Group
Technology Development Division,
Solution Promotion Office
Yanmar Energy System Co., Ltd.

In addition to the decreased demand for FAME, the customer was concerned about cases in Europe where there was a risk of dioxin contamination in SVO when added to the feed. Long-term operation with stability has been a challenge for the SVO power generation business. However, we started from repeating trial operation using different types of recycled power generation systems and managed to tackle various problems one by one. This attitude helped us gain the customer's trust and ultimately led to the introduction of large-scale power generation systems.

We helped our customer overcome challenges related to operation by leveraging the strengths of Yanmar Group, such as by establishing a task team which included experts in engines that use low-quality fuels, and through verification of data by remote monitoring. We believe our mission is to pursue initiatives that sustain society through SVO power generation, and to help our customers succeed in their aspirations for local SVO production and consumption.