Why Water and Energy Efficiency
Between 2 and 3 percent of the world’s energy consumption is used to pump and treat water for urban residents and industry. Energy consumption in most water systems worldwide could be reduced by at least 25 percent through cost-effective efficiency actions. Unfortunately, relatively little attention has been given to reducing energy use in municipal water systems.
Energy costs draw precious budgetary resources from other important municipal functions such as education, public transportation, and health care. In the developing world, energy consumed to supply water may easily eat up half of a municipality’s total budget. In municipal water systems in developed countries, energy is typically the second largest cost after labor.
The burning of fossil fuels to generate the energy used to supply water affects local and global air quality. Emissions from power plants contribute to already high levels of pollutants in the urban environment and the acidification of lakes and forests. In addition, millions of tons of carbon dioxide are emitted every year, contributing to global climate change. Global climate change is likely to reduce water tables and disrupt water supplies in many areas, making water even more costly and energy intensive to obtain in the future.
This problem is not about to go away. By 2020 developing countries will join the developed world in having more than 50 percent of their populations living in urban centers. As people move in ever greater numbers to cities, the burden of providing water to growing urban populations will become even more critical to the sustainability and prosperity of municipalities. Only about half of urban dwellers in developing countries currently have water connections in their homes, and more than one-quarter have no access to safe drinking water. Additionally, in many developing world cities, upward of 50 percent of water pumped into the system is lost before it ever reaches the consumer. Many cities in the developed world also have water losses of more than 20 percent, underutilize potential energy saving technologies, and have consumers who regularly waste water. In India larger cities such as Delhi and Bangalore lose upto 40% of the water, treated and pumped by the utility due to transmission loss and other leakages. In smaller cities the numbers are estimated to be between 50%-60%.
It is clear that cities, in the developed and developing world, waste energy, water, and financial resources because of inefficiency present within public and private municipal water utilities. This website and the Alliance’s Watergy™ Report have described the many cost-effective ways available to reduce waste and expenses, while improving overall service. Many of these actions can be undertaken by utilities with limited resources. Even the most efficient municipal water authorities have a large number of options to help maximize the efficiency with which they deliver water. These include reducing water waste and theft, improving basic maintenance practices, reducing subsidies, and optimizing system performance.
The Link between Water and Energy: Watergy™ Efficiency
In the process of improving overall water system efficiency, it is important that municipal water authorities view energy and water consumption as linked inputs, rather than viewing them as separate and unrelated. Energy is necessary for moving water through municipal water systems, making water potable, and removing waste from water. Each liter of water moving through a system represents a significant energy cost. Water losses in the form of leakage, theft, consumer waste, and inefficient delivery all directly affect the amount of energy required to deliver water to the consumer. Wastage of water regularly leads to a waste of energy. “Watergy™” efficiency can result in ensuring adequate energy supply, maintaining sufficient water supplies and minimizing environmental impacts.