Steam boilers: weaknesses and better energy option

A steam boiler produces steam for power by burning fuel. It is useful, but it has important weaknesses, and for Nepal a better source of energy is hydropower.

Weaknesses of steam boilers

1. Low efficiency. A great part of the heat is lost in flue gases, radiation and exhaust steam.
2. Fuel dependence. They need coal, oil, gas or wood, which Nepal mostly has to import or which damages forests.
3. Pollution. Burning fuel produces smoke, soot, carbon dioxide and ash, causing air pollution and global warming.
4. Danger. High pressure creates the risk of explosion if safety devices or water-level control fail.
5. High maintenance. Scale in tubes, corrosion and the need for treated water and skilled operators raise costs.
6. Slow starting and large size. Boilers take time to heat up and require space and continuous attendance.

Better option for Nepal: hydropower

Nepal has many fast-flowing rivers with large hydropower potential. Hydropower is better because:

• The fuel (water) is free, renewable and local.
• It is clean and does not pollute the air.
• Once built, running costs are low and life of the plants is long.
• It reduces fuel imports and can earn income by exporting electricity.
• Dams can also provide irrigation and flood control.
• Small and micro-hydro plants can supply remote villages, where solar energy can also help.

Therefore hydropower, supported by solar energy, is the better choice for Nepal.