| Fixed costs | Variable costs |
|---|---|
| The annual fixed cost of a plant includes interest, taxes, insurances, maintenance, depreciation, managerial, salary and rate of return | The Variable fixed cost of a plant means expenses which vary with the operation or the amount of energy produced |
| The fixed cost of the steam plant consists of cost of land , installation, equipment , design power house building , testing, commissioning etc. | The variable fixed cost of a steam plant includes the cost of coal , oil , repair , water , salaries of operating staff |
| The fixed cost of a hydro plant consists of the cost of survey , bridges, dam, earthwork, railhead, highways, other civil engineering works, powerhouse structure, design, specifications, equipment testings, commissioning etc. | The variable cost of a hydro plant includes salaries and wages of operating staff , maintenance staff and suppliers . The operating cost of hydro plant is very small |
| The fixed cost of a nuclear plant includes the cost of plant site , equipment testing and commissioning | The variable cost of a nuclear plant includes the cost of fuel , water, material, required for repair and ,maintenance , salaries of operating and maintenance staff . The operating cost is very high |