In order to reduce greenhouse gases, it is ideal to generate electricity that does not generate carbon dioxide heat generation unit / power generation / hot water supply / system, hydroelectric power generation, solar power generation, wind power generation, and geothermal power generation do not emit carbon dioxide.It will take a lot of time to expand these facilities.To prevent global warming, it is necessary to reduce carbon dioxide emissions from thermal power generation, which is the current main power source.
Carbon dioxide emissions from thermal power generation in 2018 were approximately 376 million tons, which generated 828.5 billion kWh.
Measures to reduce carbon dioxide emissions
In terms of reducing carbon dioxide from thermal power generation, the following measures will reduce the amount by about 188 million tons, or 46%.We will reduce about 7 million tons by generating electricity using the heat of combustion of general waste.Livestock manure Biomass gas power generation will reduce approximately 2 million tons.We will reduce about 2 million tons by sewage sludge power generation.
Improving the efficiency of thermal power generation
Carbon dioxide emissions from greenhouse gases from the consumption of thermal power generation coal, oil, LNG, etc. are 376 million tons, accounting for 33% of Japan's total emissions of 1,138 million tons.
| Fuel | Power generation (100 million kWh) |
Ratio (%) |
CO2 emissions (million tons) |
|---|---|---|---|
| Coal | ３,３２４ | ４１ | ２２２ |
| Petroleum | ７３７ | ９ | ３７ |
| Liquefied natural gas | ４,０２９ | ５０ | １４８ |
| Total | ８,０９０ | １００ | ４０７ |
The ratio of carbon dioxide emissions emitted to burn coal, oil and LNG to obtain the same amount of heat is 10: 7.5: 5.5.LNG carbon dioxide emissions are the lowest.
Therefore, by switching the fuel for thermal power generation from coal and oil to LNG, it is possible to reduce carbon dioxide emissions by 100 million tons.Furthermore, by using the next triple combined cycle system power generation, we can further reduce 64 million tons, resulting in a total reduction of 164 million tons.
The Triple Combined Cycle System is an extremely high efficiency thermal power generation system that uses GTCC and SOFC fuel cells that operate at high temperatures and uses the high temperature exhaust heat for combined gas turbine power generation to reach 70% efficiency.
Since the power generation efficiency of a general high efficiency thermal power plant is 47%, it is possible to increase the power generation efficiency by 23% by switching to The Triple Combined Cycle System.
General waste power generation
The Funabashi Nanbu Incineration Plant incinerates 339 tons of garbage per day. The annual amount of incineration is 85,965 tons. The total floor area is about 13,000 m2 and is a six-story building made of reinforced concrete. It is equipped with three stoker-type incinerators that slowly move garbage on the grate and burn it.
Here, there is a steam turbine generator 8400kW facility that utilizes the heat of waste incineration. This produces 53 million kWh annually. This electricity supplies the electricity required for the facility, and the surplus of 31,764,000 kWh is sold to the electric power company, and the annual income is expected to be about 540 million yen.
The total amount of garbage discharged nationwide in 2017 is 42.89 million tons.
If we build the same garbage factory, incinerate this nationwide trash, and generate electricity, it will be about 15.8 billion kWh. 15.8 billion kWh is about 2% of the amount of power generated by thermal power generation.2% is a value that reduces carbon dioxide by about 7 million tons.
Livestock feces and urine Biomass gas power generation
A diesel livestock feces and urine Biomass gas power generation from 300 cows generates 390,000 kWh annually.Since the total number of cattle raised in Japan in FY2019 is 3835,000, it will be possible to generate 5.39 billion kWh annually.
5.39 billion kWh is about 0.6% of thermal power generation.0.6% is a value that reduces carbon dioxide by about 2 million tons.The power generation amount can be increased by 8.2% by changing from diesel power generation to hybrid power generation that combines SOFC and micro gas turbine.
CO2 is generated during power generation. However, it can reduce greenhouse gases such as methane and nitrous oxide generated from livestock excrement. The result is a reduction in greenhouse gases.In addition to these, there are pigs 2503000, hens 184917, and broilers 138228. Therefore, these can further increase the amount of power generation.
Sewage sludge power generation
There is a prefectural central purification center in Shimono, Tochigi Prefecture. Shimotsuke has 24119 households and a population of 60081. The prefectural central purification center extracts hydrogen from methane gas generated in the process of treating sewage sludge and uses it for power generation.
At the Prefectural Central Purification Center, three fuel cells with a power generation output of 105 kW have been installed to generate approximately 2.5 million kWh per year.
The reasons for choosing the fuel cell are high power generation efficiency, no emission of no exhaust gas, little noise, little vibration, and easy maintenance. In addition, the greenhouse gases of methane and nitrous oxide produced by sewage sludge can be eliminated, resulting in a reduction in greenhouse gases.
The population of Japan is 126.15 million, which is about 2100 times the population of Shimotsuke City, Tochigi Prefecture. From this ratio, the annual power generation in Japan will be 5.2 billion kWh.5.2 billion kWh is about 0.6% of thermal power generation.0.6% is a value that reduces carbon dioxide by about 2 million tons.