Many people on Earth at the moment do not have access to electricity, water or gas. Many do not have domestic telephones – though in many countries now, even poor countries, most people have mobile phones. Many people cannot afford to send their children to school.
When people are so poor, the effect they have on the environment is not their first concern. Poor people might have to rely on firewood for cooking. The firewood might be found by cutting down a tree, and the water used in cooking might be found from a rapidly shrinking l;ake.
People living in this way are degrading their environment without improving their lives. Living sustainably means developing new technologies, some of them very basic, so that people can live their lives within the capacity of their environment to support them. This could include the use of biomass, so that animal waste is used to produce biogas which can be used for heat and light.
In order to live sustainably, people must reduce the amount of waste they produce and maximise their use of renewable resources.
The motor car is a very inefficient way of using energy. A car takes a lot of energy to manufacture, use and maintain, and eventually to dispose of. The bicycle is much more efficient as a way of going to the shop to buy a bottle of milk, but still many people insist on using their cars.
At Christmas every year, many people in western cities spend hundreds of pounds to cover their houses in christmas lights. This is not a sustainable use of energy, much of which is produced by burning fossil fuels in power stations. Even more crazily, many countries subsidise the price of petrol so that it costs pennies per litre, at the same time as children in those same countries are unable to go to school because their school fees have not been paid.
Quite possibly too, western countries need to reduce the amount of energy and resources they use. Rapid economic growth in developing countries is driving up the price of many raw materials, meaning that many people cannot afford the products they are used to produce. Only by finding alternatives and using raw materials more efficiently can the raw materials available be shared out in a fair way, so that everyones desire for a higher standard of living be accomodated.