The most essential resource for sustainable development is an inexhaustible source of energy. The sun is both the direct and the indirect source of energy.
Its heat, light and gravity in conjunction with the moon are the essential energy resources for life on earth. Its heat drives the convection currents - and its gravitational influence causes the tides, winds and waves. Its light converts the air and water and minerals of the earth, through the process of photosynthesis, into hydrocarbon plant life and the production of oxygen in the atmosphere – both to support animal life.
The effect of CO2 in the upper atmosphere trap the heat of the sun to maintain the air at a temperature suitable for both plant, animal and human life in the biosphere, including the production of food for animals and fuel for fire.
The technologies for capturing and amplifying these energy sources driven by the sun are well developed and are essential to sustainable development.
Solar energy is very dispersed and intermittent by comparison with the concentrated energy in fossil fuels, so technologies for energy harvesting, concentration and storage need to be used symbiotically, to meet concentrated energy demand and make permanent dependence on solar energy if viable continuous supplies are to be maintained.
An extreme example of a solar powered system is the International Space Station where the sun has been maintaining living systems suitable for human habitation for years now.
Buildings treated as SPACE STATIONS ON EARTH benefit freely from solar light and heat just by orientating toward the sun, and away from the sun for shade and coolness, also the cooling of buildings through the convection of heated air through the building to expel heated air and to provide a cooling airflow.
Passive energy conservation plays a vital role in gaining the highest benefit from passive solar heating and cooling, reducing waste and demand through thermal insulation and airtight containment - recycling energy through heat transfer and heat pump technologies to extract heat energy from expelled stale air.
Concepts like PassivHaus energy efficient housing are based on striking the most beneficial option in passive energy conservation and input, thus making the best use of solarisation, both from passive heating and cooling and the active harvesting of heat and light for heating cooing and electrical power.