Solutions for visualizing, understanding, and streamlining carbon emissions from various angles, such as business sites and products, corporate activities, and consumer behavior.
Efforts to conserve energy have been underway for several decades, but in recent years, the methods used have become more sophisticated, including AI and other technologies and billing methods based on usage. These solutions optimize energy usage.
Solutions related to batteries and hydrogen, such as electrification (EV) of mobility (means of transportation) such as cars and buses, which used to be fueled by gasoline, to reduce CO2 emissions, and to extract hydrogen for industrial use and to encourage its practical application.
Solutions related to batteries and hydrogen, such as electrification (EV) of mobility (means of transportation) such as cars and buses, which used to be fueled by gasoline, to reduce CO2 emissions, and to extract hydrogen for industrial use and to encourage its practical application.
Solutions that contribute to the fixation and absorption of CO2 in the atmosphere through forest protection and forest management, and offset the amount of greenhouse gas emissions that cannot be fully reduced through the purchase of carbon credits.
One solution is to reduce emissions in society as a whole by recycling metals, plastics, and other resources and products at various stages of economic activities.
What Is Renewable Energy? Introduction Status and Advantages
Renewable energies are being actively introduced in Japan and abroad to achieve carbon neutrality.
This article summarizes what renewable energy is, taking into account the differences from natural energy and clean energy,
The status of the introduction of renewable energies and issues to be addressed for their widespread use will be explained.
Renewable energy is energy that can be used permanently without being depleted, and at the same time is attracting attention as a clean energy source that does not emit greenhouse gases. Seven types of renewable energy are defined as "solar," "wind," "hydro," "geothermal," "solar thermal," "heat in the atmosphere and other naturally occurring heat," and "biomass. Renewable energy sources are defined as renewable energy. The energy resources currently in use are mainly fossil fuels such as oil, coal, and natural gas, but these are also known as exhaustible resources, and there are concerns about their environmental impact, such as greenhouse gas emissions, as well as the possibility that they will not be available as resources in the future. Renewable energy is attracting attention as a clean energy alternative to fossil fuels, and its introduction is being promoted.
Difference between natural energy, new energy, and clean energy
You may hear the terms "renewable energy," "natural energy," "new energy," or "clean energy" used as alternatives to fossil fuels. In practical terms, there is no problem in regarding them as synonymous with renewable energy, but the definitions of each are presented below.
Renewable Energy Renewable energy refers to energy obtained from natural phenomena, excluding biomass. Renewable energies include solar, wind, hydro, geothermal, and solar thermal.
New Energy New energy is defined as "non-fossil energy that has not been widely used due to economic constraints, and for which promotion is particularly necessary in order to introduce non-fossil energy. The term includes "solar power," "wind power," "hydroelectric power," "geothermal power," "biomass," "solar thermal power," etc. at the technological level of the time.
Clean Energy A designation for energy with low environmental impact, renewable energy also falls under the clean energy category. Nuclear power does not emit greenhouse gases, but it does generate radioactive materials, and large hydroelectric power plants may cause environmental damage when dams are built.
Renewable Energy Adoption in Japan and Around the World
Growing environmental awareness has promoted the use of renewable energies in many countries as a means of moving away from fossil fuels. Japan is also promoting the use of renewable energies, particularly solar power generation.
Japan's energy self-sufficiency rate
Japan, which is poor in energy resources, relies almost entirely on imports from overseas. Japan's energy self-sufficiency rate will be 11.3% in 2020, ranking 37th among the 38 member countries of the Organization for Economic Cooperation and Development (OECD).
Comparison of primary energy self-sufficiency rates of major countries (2021)
Renewable energies will account for 19.8% of Japan's electricity generation in 2020. Although Japan still relies on fossil fuels such as coal and natural gas for nearly 80% of its electricity, the introduction of renewable energy is being urged in order to improve energy self-sufficiency and address environmental issues.
Comparison of renewable energy as a percentage of electricity generated in major countries
Comparison of renewable energy as a percentage of electricity generated in major countries
Solar power is the main source of renewable energy in Japan
In Japan, the introduction of solar power generation has been progressing among renewable energies. Since 2012, when the "FIT (Feed-in-Tariff) system," under which renewable energy is purchased at a fixed price, began, the number of installations has increased significantly, In the five years since, the number of installations has reached seven times the initial level. Japan intends to continue to promote the introduction of renewable energies, with a focus on solar and hydroelectric power generation.
Percentage of electricity generated annually from renewable energy sources
What are the advantages and disadvantages of introducing renewable energy?
Renewable energies are increasingly being introduced as a way to address environmental issues and as a way to get rid of fossil fuels. Below are some of the advantages and disadvantages of introducing renewable energy.
Benefits of Renewable Energy Introduction
What are the advantages of renewable energy? There are three main ones: "stable energy supply," "countermeasures against global warming," and "improvement of energy self-sufficiency.
Contributing to a stable supply of energy without worrying about depletion of resources Fossil fuels such as petroleum and coal are also called exhaustible resources because they are finite and will eventually run out. In contrast, renewable energy sources, such as solar and wind power, can be used permanently. Therefore, they contribute to a stable supply of energy without being affected by resource conditions.
No greenhouse gas emissions, beneficial in combating global warming Fossil fuels emit CO2 when burned. In contrast, renewable energy is an energy source that does not emit greenhouse gases, and its introduction has been promoted in recent years as the most basic and important measure to combat global warming.
No need to import resources, contributing to energy self-sufficiency Renewable energies use natural energy sources such as solar and wind power, so there is no need to import resources from oil-producing countries, as is the case with fossil fuels, and it is possible to procure energy in one's own country. Therefore, as the introduction of renewable energies progresses, it will be possible to break away from dependence on imported energy resources and increase Japan's energy self-sufficiency ratio.
Disadvantages of introducing renewable energy
The disadvantages of renewable energy include, The disadvantages of renewable energy include: challenges in the stable supply of electricity, limited installation sites, and relatively high power generation costs.
Unstable power generation and stable supply of electricity Most renewable energy sources are affected by natural phenomena, and the amount of power generated fluctuates depending on the weather and hours of sunlight in the case of solar power generation, and wind power and wind direction in the case of wind power generation. Therefore, it is necessary to have a function to adjust the supply and demand of electricity by adjusting the amount of electricity generated according to the demand for electricity and storing excess electricity generated in storage batteries.
Large-scale facilities are required and installation locations are limited. In order to provide enough power generation capacity to meet Japan's electricity demand, and from the standpoint of power generation efficiency, it is desirable to have large-scale renewable energy generation facilities. In Japan's small land area, space for new power generation facilities is limited, and this is believed to be one of the reasons why renewable energy is not widely used in Japan.
Generation cost is relatively high According to the Agency for Natural Resources and Energy, the cost of commercial solar power generation is estimated to be 12.9 yen/kWh in 2020 and to fall to around 8.2-11.8 yen/kWh in 2030, while the purchase price of renewable electricity under the current FIT (Feed-in Tariff) system is 21 yen/kWh. On the other hand, the United Arab Emirates (UAE) "Swayhan Solar Power Project" has concluded a long-term power purchase agreement at 2.42 cents/kWh (about 3 yen/kWh), which is about 1/7 of the price in Japan. The factors that have made such low prices possible include economies of scale due to large-scale power generation plants, high equipment utilization rates due to long hours of sunlight, and the procurement prices of key components, These are some of the issues that need to be addressed in order to promote the spread of renewable energy in Japan.
Characteristics of solar, wind, and other types of renewable energy generation
Each renewable energy source has its own characteristics, and the key is to choose the appropriate energy source for your business and the situation in which you find yourself. The following is a summary of the characteristics of each renewable energy source.
solar power (generation)
It is the main source of renewable energy introduced in Japan, ranging from large-scale solar power generation for business use (mega solar) to roof-mounted solar power generation installed in factories and homes. The advantage of photovoltaic power generation is that it can be installed anywhere sunlight can reach, from small to large scale. On the other hand, the disadvantage is that the amount of electricity generated is not stable depending on the hours of sunlight.
For more information on projects related to renewable energy, mainly large-scale solar power generation projects that Mitsui is engaged in in Japan and overseas, please refer to the following.
Renewable Energy - Green & Circular - Decarbon Solution｜Mitsui & Co.
This solution supports solar, wind, biomass, and a variety of other renewable energy power generation.
Wind power is a power generation method that is expected to have the potential to generate enough offshore wind power to meet all of its electricity needs in Japan, a country surrounded by the sea. Europe is leading the way in offshore wind power generation, and Japan is in the process of acquiring knowledge of offshore wind power generation by participating in projects in Europe, which is leading the way. Onshore wind power generation, which is installed on land or along the coast, may require careful consideration and coordination for installation, as concerns have been raised about health hazards due to noise from wind turbines and infrasound emitted from wind power generation systems.
For more information on Mitsui's projects related to offshore wind power generation, please refer to the following
Supporting Offshore Wind Power from Equipment Maintenance to Achieving Self-Sufficiency in Domestic Electricity - Green & Circular Decarbonization Solutions｜Mitsui & Co.
Mitsui, together with Hokutaku, established Horizon Ocean Management, a maintenance company for offshore wind power generation facilities, and we interviewed a person in charge about the current status and expectations of offshore wind power generation and the importance of the maintenance business toward achieving carbon neutrality by 2050.
Geothermal Power Generation Geothermal power generation is a method of generating electricity from geothermal heat derived from volcanic activity. Due to the distribution of volcanoes and geothermal regions, geothermal power generation facilities are concentrated in the Tohoku and Kyushu regions. The largest power plant in Japan is the Hatchobaru Power Plant in Oita Prefecture, with a capacity of 110,000 kW. Due to the need to drill underground, the initial cost of geothermal power generation is higher than that of other renewable energy sources, and most of them are constructed and operated by electric power companies.
Hydroelectric power generation Along with solar power, this is the main method of renewable energy generation in Japan. Large-scale hydroelectric power generation uses dams, and because of the many hurdles involved in building new dams, most new hydroelectric power generation projects are small-scale.
For more information on hydropower, please visit
An easy-to-understand explanation of the structure, types, advantages and disadvantages of hydroelectric power generation - Green & Circular Decarbonization Solutions｜Mitsui & Co.
Hydroelectric power generation is a method of storing the potential energy of water by installing dams on rivers and other means, and using this energy to rotate water turbines to generate electricity. This article explains how hydropower works, its advantages and disadvantages, as well as the classifications of hydropower.
Biomass Power Generation Biomass power generation uses biologically derived resources to generate electricity. It is a renewable energy power generation method that food companies and others can easily adopt because it reuses normally discarded materials as fuel, such as livestock excrement, food waste, and woody residue. Non-food grains are also used as fuel, and sugarcane and corn for fuel are produced on a large scale in Europe and the United States.
Others
In addition to the above, various other methods of extracting energy, such as solar thermal power generation, snow and ice heat utilization, air heat, wave power, tidal power, and salinity differences, are being considered and studied for practical application.
The Future of Renewable Energy: Maximizing Renewable Energy Deployment
The introduction of renewable energy sources that do not emit greenhouse gases is an essential measure for achieving carbon neutrality in 2050. In addition, Japan, which depends on imports for most of its energy resources, is expected to improve its energy self-sufficiency ratio through the introduction of renewable energy. The spread and expansion of renewable energies is desired as it is possible to achieve both a stable energy supply and decarbonization.
