Strategies for sustainable development

Our usual ways of making power harm the environment. Thermal power plants (burning coal) give off carbon dioxide and fly ash. Large hydel (hydroelectric) projects flood forests and disturb rivers. The alternatives:

• Wind power, from windmills, in areas with strong, steady winds.
• Solar power: sunlight is turned directly into electricity by photovoltaic cells. India leads the International Solar Alliance.
• Mini-hydel plants: small plants on mountain streams.

In villages, LPG and gobar gas (biogas from cow dung) replace firewood and dried dung cakes, which pollute the air in homes. The leftover slurry from a gobar gas plant is excellent organic manure. In cities, switching Delhi's public transport to CNG (compressed natural gas) greatly cleaned up the air.

Traditional knowledge offers environment-friendly solutions too. India has about 15,000 species of plants with medicinal properties, used in Ayurveda, Unani and herbal products.

On farms:

• Biocomposting: turning farm and kitchen waste into compost. In vermicomposting, earthworms speed up the process.
• Biopest control: using nature to fight pests. Products from the neem tree work as pesticides; mixed cropping makes it harder for pests to spread; and creatures like owls, snakes and lizards eat pests such as rats and insects.