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Taking Advantage of Capacitor Technology To Enter the Power Electronics Market

Murata is always taking up new challenges, and the power electronics business is just one of them. Here, we are applying one of our strengths, monolithic ceramic capacitor technology. Technologies for power conversion and power control differ greatly from those we are familiar with. They involve different types of engineers and different extents of danger. In working on power electronics, however, Murata has an advantage. We can see the technology from a new perspective. New fields begin to develop when we start asking new questions. Murata engineers ask completely new sets of whys and why-nots, and this generates completely new ideas.

As a "capacitor house," Murata has focused on monolithic ceramic capacitors with very low power consumption. In recent years, we have been developing business in new markets such as automobiles and healthcare. Our competitive edge comes from our technology for downsizing and increasing capacitance. We are working on chargeable high-capacitance capacitors as well as next-generation energy storage devices such as lithium-ion rechargeable batteries and high-output organic batteries. Here we make use of our material and layering technologies. This is how we have developed our business in power electronics. However, products for the new market are still developed separately, and they have yet to be integrated into systems.

Concept of "Intelligent Power Supply"

Despite its traditional interest in power electronics, Murata had not gone so far as to take a comprehensive approach. Since the major natural disaster that hit East Japan on March 11, 2011, however, there has been dramatic change in people's needs for electric power—in terms of power generation and electrical storage. Ideas like "smart energy" and "energy harvesting" now draw enthusiastic attention. The world is now much more interested in how energy is to be produced.

Does "eco-friendly" mean restricting energy use or cutting off energy supplies when they are not needed? For example, the so-called "smart" approach involves storing electricity at home during low-rate night hours and using the stored power during peak hours. The aim is to even out the demand for electric power. What can Murata do to promote this aim? Optimizing the use of power generated by solar cells requires a power conversion process suitable for the application.

Specifically, DC-DC and DC-AC converters are used to achieve intelligent power supply for efficient use without loss of output. The process cannot be referred to as being "smart," however, if repeated conversion reduces efficiency. This is where the power supply technology that Murata has developed for TVs, printers, and copying machines comes in. Intelligent power supplies will be a key technology in the future.

A Power Network Encompassing Smart Houses and Electric Vehicle Batteries

As the term "smart house" indicates, the housing industry has made good progress in the "smart" use of electric power. Murata is a complete newcomer in this field, and we face the big challenge of developing successful business here.

The Ministry of Economy, Trade and Industry supports the "smart city" concept by providing subsidies, and major demonstration trials are now underway in four places in Japan: Yokohama, Toyota (Aichi Pref. ) , Kansai Science City (located around the borders of Kyoto, Osaka, and Nara Prefs. ) , and Kitakyushu. Toyota City is promoting the use of some 4,000 eco-friendly vehicles, including electric vehicles, with a focus on power generation, transmission and storage, where batteries in electric vehicles will also be utilized.

An electric vehicle has an operating range of just 100 km, but its battery can store the same amount of energy as is consumed every day in a home. The battery is recharged during the night. If you don't drive the car during the day, you can use the stored energy for air-conditioning and interior lighting. This gives you the choice of using your stored electricity in your home or to take a drive. I believe this is the ultimate smart energy. It is an interesting experiment that is connected with consumers' lifestyles.

Murata's Sensor and Network Technology will Make Sense

We can use consortiums to enter the housing industry. As I said earlier, the government funds only 4 projects on the "smart city" concept. By contrast, in the private sector, housing, electrical appliance, and home electronics manufacturers are leading more than 20 similar projects throughout the country. In each project, a consortium is organized by participant corporations. Murata is working to play an active part in some of these initiatives.

The Home Energy Management System (HEMS) is technology that visualizes how much energy is used, when and where it is used, and what it is used for. It can control all the appliances used in a house in an integrated manner and optimize the energy use automatically. The day will come when home electrical appliances, automobiles, and power generators will be managed in an integrated manner. I am convinced that Murata will be able to help develop the initial phase of such a system with its sensor and network technology.

Here, Murata sensors will be used to detect a range of parameters such as the movements of occupants, brightness, and temperature differences to send out corresponding signals. Such sensors will be networked for control as a system. That is where we can make the most of the traditional technologies we have developed for consumer equipment such as mobile phones. Our traditional customers in this area—electrical appliance and home electronics manufacturers—understand these technologies very well. They know just what Murata is able to do here. In fact, some of them have already asked us for specific solutions. We can begin by working on them.

Smart City

The "smart city" represents a next-generation social system concept that combines multiple ideas for energy use, local transport, and lifestyles. Energy consumption in the smart city features a multifaceted approach. The "smart house," the core technology that optimally controls energy use in homes, is combined with heat and power generation to achieve efficient use of energy locally. With demonstration trials already underway in many parts of the world, this innovative concept could open up a huge market in the future. In Japan, practical tests have been conducted in 4 areas selected by the Ministry of Economy, Trade and Industry: Yokohama, Toyota, Aichi Pref., Kansai Science City, and Kitakyushu.

Murata also takes part in the following smart city projects:

Research into Power Generation and Translation into Products—Slow but Steady

Murata has yet to open up new energy markets, but has made good progress in research, development and commercialization. We presented some energy harvesting products at CEATEC JAPAN 2011. These products feature technology that converts small amounts of energy existing in the environment into electricity and combines it with low-power sensors and wireless communication equipment. In fact, Murata started studying power generation technology in 2008 and has so far developed 4 power generation elements. All of these exploit so-called ambient energy resources such as vibration, heat, and light. They generate electricity within themselves and use this energy to detect things and send out signals. These wireless products offer long service life even in places that are hard to access for maintenance.

What's more, we are a member of the EnOcean^® communication alliance, developing EnOcean^® communication modules. Featuring battery-free wireless communication, the EnOcean^® technology is regarded as the best energy harvesting solution and is employed by more than 300 companies in the West.

We are going to take a slow-but-steady approach to carefully develop products like these one by one. Then we will ask our customers to use them and get their feedback. After all, I believe manufactured products cannot be completed at a stroke. One can only continue to improve them over time to bring them closer to perfection. The energy market has just opened up and there is much room for further growth. The major nuclear accident in Fukushima has made Japan's energy policy a focus of global attention. Against this backdrop, we want to find ways to contribute to the development of this new market using our proven technologies, while maintaining the sober role of a supplier.

Energy Harvesting

Energy harvesting technology converts small amounts of energy in the environment into electricity and combines it with low-power sensors and wireless communication equipment. All energy harvesting equipment exploits ambient energy resources such as vibration, heat, and light, providing maintenance-free, highly durable energy sources. Murata started studying power generation technology in 2008 and has so far developed 4 power generation elements.

1. Power generation element featuring piezoelectric material:
   Uses a piezoelectric material to convert force and vibration into electricity.
2. Power generation element featuring electret material:
   Uses an electret film to convert vibration into electricity.
3. Power generation element featuring thermoelectric material:
   Employs a thermoelectric material to convert temperature difference into electricity.
4. Power generation element featuring sensitizing dye:
   Features a dye that emits electrons upon irradiation and uses it to convert light into electricity.