The Water-Energy Nexus
You can’t have water without energy, and you can’t have energy without water. This codependency is known as the Water-Energy Nexus, illustrated below.
Here are some water and energy facts regarding the sustainability of our current water-energy nexus:
- Approximately 15-18 billion cubic meters of freshwater resources are contaminated by fossil fuel production every year.
- Energy is required for two components of water provision: pumping and treatment (before and after use).
- Hydroelectricity is the largest renewable source for power generation and its share in total electricity generation is expected to remain around 16% through 2035.
- Most of the water used for hydropower generation is returned to the river, though some evaporates, and there are important impacts on the timing and quality of stream flows.
- Wind power is the most sustainable source of renewable energy, mainly because of its low greenhouse gas emissions and water consumption.
- Roughly 75% of all industrial water withdrawals are used for energy production.
- The installed worldwide geothermal electricity capacity could be increased from the current 10 GW to 70 GW with present technology, and to 140 GW with enhanced technology.
- Currently, the City of Dallas has a co-geneneration facility at the Southside Wastewater Treatment plant that bio-digests solids and used cooking oil into methane that is then used for energy.
Read about Water and Energy Sustainability in Water and Energy Sustainability prepared for the 2014 UN-Water Annual International Zaragoza Conference.