Sustainability can be defined as the ability to maintain healthy environmental, social and economic systems in balance, indefinitely, on a global and local scale.
The spheres of sustainability can be conceptualised as having a nested relationship (Figure 1), with the economy and society a subset of the environment.
Culture is often included as a fourth circle or a subset of society.

The economy is much broader than the regular monetary economy, and includes:

• an exchange of goods and services within and between communities, with
• a focus on the equitable distribution of scarce resources
• at a sustainable scale.

Water

• Water Harvesting
  • Reuse of bath and shower water for toilets
  • Rain and storm water

Electricity

• Energy Harvesting
  • Solar Panels
• LED Lighting

Waste

• Packaged Sewage Treatment Plant
• Recycling

Gas

Gardens

• Compost
• Vegetable
• Vegetation