Energy savings achieved through power monitoring at rubber plant

Founded in 1917, the Yokohama Rubber Company manufactures various types of tyres for passenger cars, trucks and buses, construction vehicles, industrial vehicles, agricultural and forestry machinery. It also manufactures conveyor belts, bridge and civil engineering materials, and aviation components as well as sporting goods. The company’s plant in Onomichi City, Japan, began production in 1974 and specialises in the production of large tyres for construction and industrial vehicles that operate in mines, ports and other demanding environments.

The tyre manufacturing process requires a large amount of energy, especially in the scouring process for mixing raw materials. In response to the drive for carbon neutral manufacturing, Yokohama Rubber is working on energy conservation initiatives with the initial goal of reducing its greenhouse gas emissions by 28%, compared to 2019, by 2030. Longer term it plans to achieve net zero CO₂ emissions by 2050.

The company has already reduced the use of electricity through the introduction of modern inverters while other energy-saving measures have resulted in other significant reductions in fuel costs. Aiming to go further and create a world-class energy-saving program, engineers from the Onomichi Plant visited Mitsubishi Electric’s Fukuyama Works, which showcases energy conservation techniques in its own operations.

On visiting the plant, Kazuyoshi Yanagisawa, Manager of Onomichi’s Engineering and Maintenance Section, commented that: “While their products are different from ours, I realised at once that the factory’s energy efficiency is superb, thanks to the monitoring and analysis systems they have developed.”

Based on their tour of the Fukuyama Works, Onomichi’s Engineering and Maintenance Section developed an energy-saving data collection system based on Mitsubishi Electric’s EcoWebServer III. This collects energy information from around the factory and displays it on a PC connected to the site’s existing internal computer network. The system means power consumption can be visualised in near real time, making it possible to plan effective energy-saving measures.

“We quickly discovered via EcoWebServer III that power consumption was fairly constant throughout the day,” said Takeshi Matsushita of the Engineering and Maintenance Section. “Surprisingly, it did not drop much during periods of low production. This was because the main water pump was operating all the time, even when a pressurised supply was not required. This was a quick fix with an immediate payback in terms of significant energy savings.”

It was also realised that power consumption was not dropping significantly during the night when production was also lower. After consulting with the appropriate personnel, new procedures were developed ensuring compressors were turned down or off when not needed. This simple initiative led to further energy savings both at night and during the day when major production equipment was not in use.

To enhance the energy-saving effects of EcoWebServer III, Yokohama Rubber has also installed EcoAdviser at the Onomichi Plant. EcoAdviser is an energy-saving support application that graphically visualises energy information collected by EcoWebServer III in an easy-to-understand manner that can be seen by all personnel.

“It is only natural that we energy managers want to see and understand fully detailed energy information,” said Kazuyoshi Yanagisawa, Manager of the Engineering and Maintenance Section. “However, it is the operators onsite who actually use the energy. We realised that in order to increase onsite motivation for energy conservation, clear simple graphics display via EcoAdviser would be an ideal solution.”

To help with implementation, the company adopted the EcoAdviser Utilization Support Service provided by Fukuyama Works. This includes screen creation training and basic screen creation services to get the system up and running quickly. The training has been effective, and now the staff members are able to create new screens on their own.

Yokohama Rubber designates June every year as ‘Environment Month’, when each department at the plant competes in energy-saving activities. The EcoWebServer III and EcoAdviser played a major role in the most recent Environment Month.

“Previously we could only describe the results rather than quantify them,” Matsushita said. “However, EcoWebServer III and EcoAdviser have made it possible to visualise the effects of actions such as turning off wasteful lighting in a way that can be understood by everyone. Showing the actual power-saving figures really motivates each department.”

In addition to Environment Month, the Engineering and Maintenance Section now uses the figures to disseminate information to all personnel via a regular in-house e-newsletter entitled Energy Conservation Communication. By copying the EcoAdviser screen into the newsletter, specific information can be given in an easy-to-understand way.

Not content to rest of their laurels, Onomichi is now considering integrating management of energy sources other than electric power, such as boilers, steam and cooling water, into the EcoWebServer III/EcoAdviser system.