Food and Water
World agriculture is the most important driver of human land and water use, as well as a major factor in climate change.
The greatest opportunity for reducing impacts of agriculture is in switching to plant-based diets, or at least in reducing consumption of beef and mutton. Lesser savings are possible through expanding use of no-till farming, genetic modification, and precision farming, though these trends are driven largely by economics. Organic farming generally saves energy at the cost of more land, while forms of intensive farming, such as greenhouses and power-to-food, save land at the cost of energy. Additional modest savings are possible through reducing food waste, overeating, and localized food production, though it is unclear how much food waste can be reduced, and local foods can have drawbacks from being grown in suboptimal climates.
Most of the world's water use is for agriculture, with thermal power a major secondary use.
In the United States, where power generation is a larger share of water withdrawal, the following savings opportunities are observed.
While plant-based diets, drip irrigation, dry cooling and non-thermal power, and efficiency in cities and industry can reduce water needs, pressure on fresh water supplies can also be relieved by supplying water though waste water recycling and, as a backstop, desalination.