energy

energy & environment
co2-emission-and-target-Japan
Carbon dioxide in Japan - reduction target

Japan nowadays emits 1.2 billion tones of carbon dioxide annually. Beccause the environmental issues are said to have originagted from the increase in the concentration of green-house gases, goverments put efforts in stopping the increase. This post shares with you the target of reduction in the GHG emission set by the Japannese goverment.

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energy & environment
English-co2-emission-by-sector-in-2019
Carbon dioxide in Japan - emission amount

Things that come to one's mind when hearing environments, energy.... that would be green house gas emissions. Today, let's have a look at carbon dioxide emissions.

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energy & environment
correlation-of-hydrogen-cost-wtih-electrolyzer-capacity
How to produce hydrogen - 3

Water electrolysis, water splitting driven by renewable electric power, can contribute to achieving the sustainable society. Its history and overview were summarized in the previous post. This post takes a step ahead, and shall detail the price of hydrogen produced by the water electrolysis.

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energy & environment
history-of-water-electrolysis
How to produce hydrogen - 2

The previous post touched upon the methodes of producing hydrogen (see How to produce hydrogen - 1). "How to produce hydrogen using renewable electricity" - one solution to this challenge is water electrolysis. Most of you supposedly learnt about water electrolysis in high school. This post introduces briefly the water electrolysis, with a bit more details than what you had learnt in the past.

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energy & environment
share-of-primary-energy-hydrogen-production-2014
How to produce hydrogen - 1

Being the most representative energy carrier, hydrogen has been of great focues nowadays. A seires of posts, starting with this one, shall focus on the production of hydrogen; especially this post summarizes how the hydrogen has currently been produced.

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energy & environment
renewable-energy-potential-japan
Can renwable power generated in Japan meet the energy demand in Japan?

Ultimately, energy demand needs to be fulfilled by renewable power in a sustainable society. In the case of Japan, is it possible to meet the energy demand only by utilizing renewable energy?

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energy & environment
irradiation-area-required-to-supply-energy
Let's use solar energy! How large does the area need to be?

Our society consumes quite large amount of energy, mostly relying on fossil-fuels, and our demand of energy shall keep increasing as a whole. To supply the energy demand in coming future, renewable energy needs to be utilized (see The amount of energy we consume). Thinking of sunlight as a model, one may notice that energy amount depends on the area of irradiation. Let's see in this post how large the area needs to be to supply the energy to the world.

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energy & environment
comparison-of-energy-densities-of-carriers-with-examples
How to store energy -5

Hydrogen exists in gasous form in the standard condition due to its quite low boiling point, meaning that it is difficult to store and transport. This drawback, however, does not lead to a conclusion of giving up the use of hydrogen, because hydrogen also has another strong benefits in its production and usage. Hydrogen and its derivative are to be discussed in the series of posts, by considering "how small the volmetric energy density can become".

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energy & environment
comparison-of-energy-densities-of-carriers
How to store energy -4

Hydrogen exists in gasous form in the standard condition due to its quite low boiling point, meaning that it is difficult to store and transport. This drawback, however, does not lead to a conclusion of giving up the use of hydrogen, because hydrogen also has another strong benefits in its production and usage. Hydrogen and its derivative are to be discussed in the series of posts, by considering "how small the volmetric energy density can become".

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energy & environment
volmetric-and-weight-density-of-energy-carrier
How to store energy -3

Hydrogen exists in gasous form in the standard condition due to its quite low boiling point, meaning that it is difficult to store and transport. This drawback, however, does not lead to a conclusion of giving up the use of hydrogen, because hydrogen also has another strong benefits in its production and usage. Hydrogen and its derivative are to be discussed in the series of posts, by considering "how small the volmetric energy density can become".

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