The depreciation rate is 1/20 = 5%.
According to current national standards and hydropower industry practices, hydroelectric generators typically have a lifespan of 20 to 25 years. Taking 20 years as an example, the depreciation period is 20 years and the depreciation rate is 1/20 = 5%. This means that over the life of the hydroelectric generator, a corresponding depreciation charge of 5% of the cost of the equipment can be recognized each year to calculate the company's pre-tax profits.
For the specific depreciation rate of hydropower generation equipment, specific accounting and calculation should be carried out according to the actual situation, and the depreciation expenses should be calculated and provided under the direction of an accountant or tax specialist.