Thermal power generation plays a pivotal role in the supply of electricity since it enables a flexible response to changes in demand. TEPCO Fuel & Power is engaged in a variety of efforts to provide a stable power supply and operate as inexpensively and economically as possible. This includes making the most of the properties of various types of fuel and power generation methods utilized at thermal power stations.
In order to generate less expensive electricity, we operate the power generation facilities at our power stations by prioritizing them according to their calculated thermal efficiency and costs related to power generation (unit price of power generation). We also adjust the order of priority in which the facilities are operated whenever necessary according to the LNG terminal or coal inventory, system constraints, repair work, and other factors.
To reduce fuel costs, we are expanding the operation of coal-fired power units, high-efficiency LNG-fired power units, and other low-cost power sources as much as possible, and are trying to minimize the use of oil-fired power units and other high-cost power sources.
Fuel consumption fluctuates with the demand for electricity. We are also planning the quantity of fuel to receive on an annual basis, and will make corrections as needed. Therefore, we will take fuel inventories into consideration for economical power plant operation.
The types of fuel used at a thermal power station include coal, LNG, and oil. LNG accounts for about 70% and represents an indispensable fuel source for the operation of thermal power stations. In order to ensure that our customers receive a stable supply of electricity, we take an integrated approach to our operations. This includes utilizing the gas pipelines that connect our three terminals (the Higashi-Ohgishima terminal, the Futtsu terminal, and the Sodegaura joint terminal) to manage our inventory while taking into account various elements, such as the constantly changing amounts of generated power and fuel inventories, and LNG carrier delays due to weather and sea conditions.
Since electricity cannot be stored, we adjust the supply (amount of generated power) from our power stations to maintain the balance (50 Hz) according to trends in society and the constantly changing demand (amount of power used).
Thermal power generation plays a pivotal role in the supply of electricity since it enables a flexible response to changes in demand.
Thermal power stations provide the adjusted amount through supply and coordination capabilities (by starting or stopping generators and adjusting the output) according to orders issued by the Central Load Dispatching Center and by using the self-control systems of the power generators.
Through increased solar power-generated electricity, coordination capabilities are continuously enhanced so that the thermal power generation facilities are operated economically.
By adjusting middle/peak-load thermal power generation according to solar power generation, consistent operation (high operation rate) of low-fuel-cost base-load thermal power generation is maintained.
With further expansion of solar power generation, there is concern that the adjustment of middle/peak-load thermal power generation alone will be insufficient, and that low-fuel-cost base-load thermal power generation will not be able to be consistently maintained (operation rate will drop).
Enhanced adjustment of middle/peak-load thermal power generation will enable solar's expansion to be handled, and consistent operation (high operation rate) of low-fuel-cost base-load thermal power generation will be maintained.
*Base-load thermal power generation: [Fuel] coal, LNG (high efficiency); Middle/peak-load thermal power generation: [Fuel] LNG, LPG, city gas, heavy oil, crude oil