The efficient use of waste, a substitute for fossil fuels, can play a significant role in promoting the mitigation of climate change. In Japan, power generation at incinerators has been the mainstream way of recovering energy from waste. However, particularly at an incinerator for municipal waste, power generation efficiency is limited to around 20 % or more due to the presence of corrosive components in the combustion gas. For the fundamental improvement of energy efficiency, heat supply from incinerators needs to be considered. However, the value of heat varies greatly depending on its temperature. Low-temperature heat for space heating and hot water supply can be efficiently supplied by a heat pump. In addition, electricity to operate heat pumps can be supplied by renewable energies such as solar-power generation. Development of competing technologies to supply heat needs to be thoroughly examined at this same time. This article first explains the importance of taking energy quality into consideration. The effectiveness of supplying steam from an incinerator to factories that have a demand for high-temperature heat is introduced next, along with the incorporation of supplying low-temperature heat using waste heat.

View full abstract

This paper introduces the direction of The Fifth Basic Environment Plan laid out by a 2018 Japanese Cabinet decision. It includes The Forth Fundamental Plan for Establishing a Sound Material-Cycle Society and The Waste Treatment Facility Preparation Plan. In addition, contents of a policy aimed at reducing carbon in the waste industry and centering on waste treatment facilities such as waste incineration facilities, is more specifically outlined in The Waste Treatment Facility Preparation Plan. As a measure to promote this lowering of carbon in the waste industry, the paper reports on the establishment of technical assistance, such as the formulation of assistance for introducing equipment and guidelines for utilizing waste energy. The paper concludes with authors proposing to establish a Regional Circulating and Ecological Sphere within the core of waste treatment facilities. This would be realized through the promotion of efforts to utilize waste energy.

View full abstract

This article summarizes the regulations established for district heating in countries that have adopted a certain degree of waste incineration to manage their own waste and to utilize heat recovery as a district heating supply. The article goes on to argue the implications surrounding appropriate regulations for the case of Japan. The regulations for district heating in major countries fall into two categories: those with a range of economic incentives (i.e. price regulation) and those that are market based. The former is generally beneficial to those facing less competitive heating as compared to other alternatives such as electricity. According to the research, this type of regulation is found to be suitable for Japan. It is important to note that district heating for household demand is popular in countries with relatively cold climates, which is not the case for Japan, except for a few limited regions. It has a greater potential, however, for application in the industrial processes. In order to promote heat recovery from waste incineration plants as an energy source for industrial district heating systems, additional regulations that act as motivation to locate incineration plants in or near industrialized areas will be beneficial.

View full abstract

Since the oil shock in the 1970s, district heating has been actively introduced in various European countries with an aim to more effectively utilize fossil fuels. This is especially noticeable in Northern Europe where there is a large demand for heating. Denmark aims to achieve a zero-fossil fuel target and achieve 100 % renewable energy by 2050, putting into progress research and demonstrations for the transition to 4th generation district heating (4DH) while this trend spreads to about 60 % of the total population. In this paper, trends toward 100 % renewable energy and decarbonization in the heat sector using renewable energy are summarized as they pertain to European climate change and energy policies under the Paris Agreement. Based on case studies that show this transition toward 4DH in Denmark, the prospects of promoting district heating in Japan are also considered. For issues related to renewable energy heat utilization, it is expected that various efforts will be further advanced by adopting know-how from European countries along with the potential of renewable energy, such as biomass, in Japan.

View full abstract

The European Union (EU) has been working on building a circular economy (CE) since 2015. The CE concept aims to maximize resource utilization efficiency in various ways, mainly through the promotion of repair, sharing, and life extension as well as reuse and recycling. Although waste-to-energy (WtE) is positioned low in the waste hierarchy presented within the CE, WtE may still be effective for wastes that are difficult to sort and clean. Among EU countries, Austria shows one of the highest levels of waste material and energy use; a municipal waste flow analysis indicates that improvement of the sorting process may be the main contributing factor for this. In addition, effective WtE in the country has been realized by the management with Stadtwerke (city public corporation) and the existence of the regional heat supply network. Elements extracted from such cases in Australia will be an important reference for taking sustainable material cycles into consideration in other regions, including Japan.

View full abstract

This article reports the actual conditions at steam exchange projects between incineration and industrial plants in Ulsan industrial complex and the learnings gleaned from the program, which has been promoted by Korean National Eco Industrial Park (EPI) Plan from 2005 to 2019. A strategic scheme in Korea to promote EIP projects is outlined in this paper. The key actors are regional EIP centers, which work to raise awareness, negotiate with stakeholders, and accumulate knowledge and know-how regarding business models. As a best practice, the EIP project between an MSW incineration plant and a chemical plant in Ulsan is described in detail. The author concludes by proposing the establishment of intermediate organizations to promote EIP projects in Japan, based on the results of implications from this Korean experience.

View full abstract

Stable energy recovery is essential to developing profitable Waste-to-Energy (WtE) projects that can contribute to low carbonization. In this model project, a simulation was conducted using a WtE plant located close to chemical plants that require significant amounts of heat. Flammable waste, such as plastics, was collected from a wide range of sources to be converted into energy. Both the composition and the amount of treated waste is controlled by an Internet of Things (IoT) system. The objective of this report is to study the feasibility of this project and analyze the amount of carbon being emitted. Results prove that the whole system can realize a sustainable energy supply, connected to efficient waste treatment and economical energy utilization in local communities. Because many production processes at chemical plants operate 24 hours a day/365 days a year, they are able to collaborate perfectly with WtE plants as constant energy consumers.

View full abstract