In the long term, there are a variety of possibilities for securing the world's energy future. These include renewable energy sources, which are fast becoming economic. For example, there have been rapid advances in efficient solar cell-based power generation. Biomass, wind, and other sources of renewable energy are also becoming realistic options for niche uses.
Public acceptance of nuclear power will depend on the safe operation of nuclear plants and the safe management of the radioactive wastes produced by these facilities. Safe nuclear power represents an indispensable resource, opening up new options for energy supply, use, and distribution. Nuclear fusion is a possible future source of energy.
Public infrastructures are essential to the efficient functioning of society and its ability to achieve sustainable development. These include water resource and supply systems, power systems, bridges, roads, as well as communications and transportation facilities. To a large extent, the technologies are well developed. The essential challenge lies in the diffusion and use of such technologies to developing nations, where they are most needed.
Water treatment and re-use will have a decisive role in sustainable development in the public, industrial, and agricultural sectors. In the public sector, securing public health will remain the basic feature of urban water systems; water transportation and treatment