Integrated energy and water management will boost savings in industry

The world has a water problem and industry can be part of the solution. Half the world’s population experiences severe water scarcity for at least part of the year, with poorer communities worst affected, threatening livelihoods, health and economic output. Industry could help address these scarcity issues by reducing their own water use and increasing energy efficiency.

Globally, the industrial sector is the second biggest user of freshwater after agriculture, accounting for just under 20% of freshwater withdrawals while simultaneously being the largest user of energy, accounting for almost 40% of the world’s total annual energy consumption.

While water and energy are often managed as separate resources in industry, adopting an integrated approach that combines energy and water management can improve energy efficiency and reduce water losses. Efficiency measures that lead to water and energy savings can lower water and energy bills, create jobs, lower emissions and reduce risks related to water scarcity. Many synergies emerge from an integrated view of energy and water management.

Water is essential for almost every aspect of supplying energy. Water is used in energy extraction and transformation for process cooling and other operational needs, and it is also used for the transportation of fuels and energy goods. On average, the global energy sector withdraws around 0.6 billion cubic metres (bcm) of freshwater for each 1 EJ of energy demand. By reducing energy use, water is saved too.

There are many inefficiencies in energy use in the industry sector. A recent analysis of the manufacturing sector in the United States, shows that just under 50% of all energy used onsite for manufacturing is lost. Globally, increased uptake of energy management and of AI-enabled savings in industry could result in 28% less energy being used to produce the same unit of value added in 2035.  Considering the average volume of water needed to supply energy, this energy demand reduction would correspond to roughly 17 bcm less freshwater being withdrawn – that’s the same amount of water all municipalities in Sub-Saharan Africa used in 2020.

Globally, about 30% of freshwater is wasted due to leaks and inefficient use. This leads to more energy being used to extract, treat and transport larger volumes of water. In some countries, average losses in water supply and treatment systems reach 60%. Water users are also responsible for substantial losses. Analysis by Thames Water in the UK indicates that more than 25% of the water supplied to business customers could be lost due to leaks on premises. Some industrial sectors experience water losses as high as 50% due to leaks, outdated equipment, and inefficient practices.

Water leaks and inefficient use also lead to higher costs. Electricity costs typically account for 25–40% of a water treatment plant’s operational expense. Energy costs constitute almost 50% of the operating expenditures of desalination plants. Many industries, such as the semiconductor, pharmaceutical and food and beverage industry rely heavily on ultrapure water (UPW), which comes at an even higher energy cost for treatment (4 - 18 times more when compared to drinking water).

Combining energy and water management could help slash both energy and water losses and reduce costs. Integrated approaches, combined with better data, can provide a full assessment of costs and benefits of efficiency measures, including upstream and downstream impacts. Integrated energy and water audits, for example, could save companies time and money. Also, industry can often use water that has lower quality and is available on-site, such as process water or treated wastewater, reducing freshwater demand and saving on energy costs associated with water transportation.

There is emerging evidence that water conservation programmes can, in some cases, deliver even more energy savings than programmes that focus on energy efficiency alone. Implementation of water audits and recommended measures at industrial sites have been shown to deliver water savings in the range of 10-50% with additional savings of up to 20% in reduced costs for energy and water treatment chemicals.

A comprehensive analysis of water and energy use by the manufacturing sector in the United States indicates that investing in water efficiency is ten times more cost effective than investing in alternative water supply, and could result in water usage reduction of 60%.

Systematically linking energy and water management could unlock synergies while contributing to more resilient manufacturing operations – especially in times of rising energy and water costs. More integrated policy approaches to water and energy can support the achievement of multiple policy objectives. To this end, energy ministries and energy efficiency agencies can:

• Increase the uptake and consistency of water and energy audits in the industrial sector. This can be done by including a distinct focus on water efficiency in energy audits, by incentivising integrated water and energy efficiency audits, and by including water efficiency in energy auditor training programmes, as is the case in India where mandatory requirements are in place for large consumers.

• Include water usage in energy surveys and benchmarking studies. The US Energy Information Administration now includes water use when it surveys energy use in over 46,000 commercial buildings, allowing benchmarking by floorspace and per person. In Singapore, it is mandatory for large water using businesses to report their consumption data. This data is used to compile benchmarking information for a range of sectors.

• Foster cooperation by working jointly with agencies responsible for both energy efficiency and water resources on the water-energy nexus and set up joint programmes. A multi-donor funded water and energy programme has been running in Central Asia since 2009.

• Raise awareness about the interlinkage between water and energy efficiency in industry through training programmes as has been done in Malta – or through the inclusion of water efficiency in recognition or rating schemes as has been done by the National Australian Built Environment Rating System.

• Encourage industry to move towards integrated management of energy and water, as has been done by the US Better Plants programme, where the energy savings program has expanded to include water savings.