Udon Noodle Waste Collected at Bio-Refinery Plant. Credit: Chiyoda Seisakujo.

Udon Noodles to Create Udon Noodles

Kagawa prefecture is well known as a home of “sanuki” udon — square shaped noodles made by kneading together wheat flour, salt, and water. Sanuki udon noodles have a strong “koshi” (an al dente or firm-bite consistency). While many people enjoy and consume udon noodles daily, the prefecture faced a problem with a massive amount of udon noodle scraps from noodle manufacturers and unsellable noodles at local noodle shops.

Chiyoda Seisakujo, an industry equipment manufacturer located in Takamatsu city, the capital of Kagawa prefecture, has been developing biogas plants since 2004. Two prefecture-owned technology research and development centers approached the company, asking to utilize udon noodle waste as an ethanol feedstock.

In 2012, the company developed a prototype bioethanol plant on its property. The company collected udon noodle scraps from a large local noodle manufacturer. “With 1,500 kilograms (3,307 pounds) of udon scraps, we can produce about 200 litters (53 gallons) of bioethanol,” said Testuo Ozaki, a representative at Chiyoda Seisakujo.

From Udon Waste to Udon Ethanol. Credit: Chiyoda Seisakujo. 

The company noticed that there was still a lot of residue after producing bioethanol from udon waste. By using its expertise, the company built a biogas plant and further fermented the residue to produce methane gas. With methane gas, the company can produce annually about 180 GWh of electric power. “We started selling electricity to our local Shikoku Power Electric Company in December 2013,” said Ozaki.

To make the transformation of udon waste into clean, locally-produced energy a statewide effort, a consortium was created among udon noodle makers, restaurants, local research centers and local governments, along with Chiyoda Seisakujo. The consortium launched a program called the “Whole Udon Cycle” to transform udon noodles to fuels, electricity and products.

The “Whole Udon Cycle” consists of two parts: (1) boil udon with udon, and (2) make udon from udon.

At noodle shops, if udon is not served in a timely manner, it loses koshi and ends up in a trash can rather than a bowl at a table. The consortium started collecting udon waste from local noodle shops. The waste is taken to the bioethanol processing plant owned by Chiyoda Seisakujo. Eternal produced at the plant is distributed back to the local noodle shops to boil water in which to cook udon noodles.

Furthermore, Chiyoda Seisakujo turns the residue from post-biogas production into wet fertilizers. The consortium distributes the fertilizers to local wheat fields, which produce a main ingredient to make udon noodles.

Udon Bioethanol and Biomass Plants. Credit: Chiyoda Seisakujo.

“We (Chiyoda Seisakujo) have developed the ethanol and methane gas plants for udon waste as a pilot project on our property. We got a lot of visitors and traction in the plants. We also got an order for commercial use. This (plant system) can be applied not only for udon waste outside of Kagawa prefecture, but also for any food waste anywhere in Japan,” stated Ozaki.  

Converting Mandarin Orange Waste into Bioethanol

Ehime prefecture, bordering Kagawa prefecture on the east, is the number one producer of mandarin oranges in Japan. Over ten years ago, the prefecture developed a biomass utilization plan to reduce green gas emissions and industrial waste while promoting locally-produced energy for local consumption and creating environmental jobs.

In 2008, the prefecture, Ehime University, and Nippon Steel Engineering Company teamed up together, with a grant awarded from the Ministry of Environment, to run a pilot project to transform orange waste into biofuel.

Nippon Steel Engineering constructed an ethanol bio-refinery at an orange juice processing plant owned by Ehime Beverage Inc., which collects most of the oranges harvested in the prefecture.

Mandarin Orange Waste and the Orange Ethanol Bio-refinery at Ehime Beverage Inc. Credit: Ehime Prefecture.

“About 20,000 tons of oranges are processed for juice production, of which 50 percent ends up as waste including seed, peel, and segment membrane,” said Sadanomi Minakuchi, an environmental technology engineer at the prefecture’s environmental department.

“We produced 48.6 kiloliters (12,839 gallons) of ethanol from the orange waste we collected in 2013. We only ran the plant for two months — November and December. In Ehime, we harvest mandarin oranges only in the fall and not throughout the year like in California,” continued Minakuchi.

The research team has been testing various applications for orange waste-based ethanol and inspecting types of power equipment which can withstand corrosion by ethanol gasoline blends.

“We mainly use the orange ethanol for farm equipment and boiler systems to provide heat for greenhouses that produce tomatoes and cucumbers. But not for vehicles. In Japan it is almost impossible to sell ethanol (as gasoline). The powerful oil industry won’t let us sell the E3 (gasoline blended with up to 3 percent of ethanol),” said Minakuchi.

“The cost of producing orange ethanol is currently about ¥202 per liter (US$6.42/gallon) while one liter of gasoline costs ¥140 (US$4.45/gallon) in Japan. We won’t be able to compete against gasoline now, but our goal is to provide orange ethanol as vehicle fuels under the “Ehime” brand. In order to do so, we need to scale up the size of the bio-refinery plant and need to run the plant throughout the year by finding other biomass feedstock besides orange waste. We are also asking the federal government to open up the ethanol market for transportation,” continued Minakuchi.

Utilizing another bioenergy resource, Shikishima Brewery in Miyazaki prefecture has been producing “imo-shochu” — distilled liquor from sweet potatoes since 1917. The company decided to convert potatoes’ starchy residue from the distilling process into biogas, which is started in September 2014. It can produce 4 GWh of biogas annually and is selling electricity to a local utility at a rate of ¥39/kWh (US$0.33/kWh) (pre-tax) for the duration of 20 years under the FIT program.

2015 — The Year for Biomass in Japan?

According to the latest numbers released by the ministry of Economy, Trade and Industry (METI), almost 13 GW of PV capacity has been installed under the FIT program from July 2012 through December 2014, while only 90 MW of biomass capacity has been installed during the same period. PV represents 98 percent of the total renewable capacity installed under the FIT, while biomass represents less than 1 percent.

In terms of installed capacity, biomass is minuscule; however, in terms of electricity generation, biomass represents about 14 percent of all the renewable power purchased under the FIT while PV represents 56 percent.

There is currently 69 GW worth of PV capacity approved but not yet installed under the FIT program. The nation’s electric utilities are seriously concerned that the PV energy supply will exceed their energy demand and weather-depending PV power output.

To diversify the nation’s renewable energy mix, the METI is currently encouraging the development of community-based biomass plants.   Power output from biomass can be easily controlled and biomass provide environmentally-safe waste management and disposal. Biomass production also stimulates local economy by utilizing locally-available biomass feedstock and continuing to provide employment opportunities even after the construction of biomass plants are completed.