Energy, Water And Climate Change

Energy is connected to water as water is connected to energy while both are influenced by climate change, further altering the dynamics of this relationship.

A growing world population means more energy and water will be needed.

Energy is used in withdrawal, transport, processing and cleaning of water. Water withdrawal refers to removal/collection of water from source. Energy is used to pump water from surface water (lakes, springs, rivers and even oceans) and transport it to processing plants. Here, the water is cleaned and purified according to its various purposes. Large scale distillation and chlorination, done to make water potable (drinkable) all require quite the amount of energy. Energy is then used to transport and distribute this water to households.

The Kaptis Hydropower plant (image: Africa Energy Portal)

Industries and farms require a different quality of water but energy is also used in water treatment and transport/ distribution especially over long distances. The amount of energy used depends on both the distance therefore transport needs and the amounts of water needed. Piped water is pumped from the water processing plant while water can be transported manually by bowsers and other vehicles. All use energy.

For places that rely on groundwater, energy is used to access underground aquifers (water bearing rocks), drill them and pump the water upwards for consequent processing, distribution and use. In times of drought, insufficient rainfall, growing population pressures and poor water use, this extraction increases significantly.

Groundwater has a higher amount of dissolved salts unlike surface water and so requires more energy for processing and chemical distillation before it becomes fit for drinking and other uses. 

Water scarcity therefore directly increases the cost of energy used.

Energy is used for wastewater treatment before discharge. In most countries, laws and regulations require that wastewater be cleaned properly before discharge into water bodies such as rivers and lakes. For the most part, this requires removal of solids, dissolved organic matter and salts (nutrients) and in some, disinfection. Some processes are natural, others need mechanical distillation while others use chemicals. All require energy as much as transport of this water does.

Another water and energy process is desalination. Desalination refers to the removal of salts from seawater to make it sufficient for use. It is an energy intensive process and expensive. However, it is necessary in countries that suffer water stress such as North Africa or Arabic countries. Additionally, with a changing climate forecasted to increase water stress in different regions globally, desalination will be used more frequently to satisfy water demand. This in turn increases energy use and consequently increases the cost of both water and energy.

Now, as it stands, the energy used in the all the above mentioned processes is usually from fossil fuels. Road transport uses oil. When electricity is used in any process, it is mainly generated from coal power plants/ thermal power plants. Therefore, a large share of the energy is non-renewable. Fossil fuels release carbon emissions into the atmosphere. In some countries however, renewable sources such as hydropower, nuclear and to a growing extent solar or wind are used to generate electricity which is then supplied to the main grid. Off grid power can also be used to in desalination and other processes.

Agriculture and industry are the leading sectors globally that use water. Irrigated agriculture uses energy to pump and distribute water. Industry requires energy for transport and distribution of water and also uses water in industrial processes (cleaning and cooling and as an ingredient in products).

On the other hand, water is a part of energy production. Water is used to generate hydropower from dammed rivers. It is used in extraction of fossil fuels especially coal and oil. It is used in thermal power plants as a coolant. For the same reason it is used in nuclear power plants.

Lack of enough water directly causes the price of energy to shoot up because of the critical role water plays in all these energy generation processes.

All the aforementioned use plenty of water and so place a considerable demand on water supply. This is why for the most part, such plants are located near water sources. Otherwise, considerable costs are incurred in water withdrawal and transport.

Hydropower is a relatively cheaper and carbon free source of energy but is directly faced by the impacts of a changing climate.

Water is used to a lesser extent in solar photovoltaics and wind energy for cleaning. However in concentrated solar power (CSP), more water is used in the energy production process.

There are several risks associated with energy and water. One is that the higher the energy needs the more water is extracted. The amount of water withdrawn from a source increases and this increases competition with other water needs such as ecosystem use (the natural world), agriculture and household consumption. There is also the issue of fair and equitable sharing of water sources (and also derived energy) between host communities and other end users.

Another issue is the sharing of transboundary water resources. These are waterbodies that straddle national or regional borders. The use of such water bodies by any participant country has to be done with due regard to the needs of the other countries.

Groundwater extraction can pose a problem because of insufficient recharge rates from rainwater and surface water. Also, some aquifers are sandwiched between two impervious layers of rock. Therefore such aquifers cannot be recharged and once depleted the water is finished. And this means water scarcity.

Coastal freshwater aquifers providing drinking water are threatened from encroachment by sea water making them saline. That is, depleted layers of permeable rock previously holding freshwater will now contain saline water unfit for use. The consequences for coastal communities is big, especially given that many seaside cities are important centers of trade and government.

Now, climate change affects precipitation patterns. It does this through affecting the timing, seasonality, geographical variability, duration, quality and quantity of rainfall. Climate change caused droughts and heat waves increase evaporation rates from water bodies and deplete surface water. They also increase transpiration from plants. They directly cause water scarcity which consequently affects everything else.

Invariably, these impacts increase water demand on its own, and also affect energy prices because more energy is needed to satisfy cooling needs, and energy generation requires water.

Climate change leads to a lesser snow pack meaning lower amounts of water in summer. This increases demand and so more groundwater extraction.

The costs of energy shoots up because more water is needed in thermal power plants as they increase output. More energy is also used as attention turns toward increased pumping of groundwater and desalination of sea water to satisfy demand. Lesser amounts of water available in dammed reservoirs mean a higher cost of power as the share of hydropower diminishes and thermal plants which are more expensive takeover. This translates to more climate pollution as more fossil fuels are used.

When there’s too much rain and resultant flash floods, energy facilities can be submerged. Also, more energy is required to pump out water from different areas. Wastewater plants can be flooded and this poses the immediate risk of waterborne diseases from contaminated water. Typhoons can knock out power supply.

Sea level rise, a result of climate change, directly increases the cost of energy because the water encroaches inland and so contaminates freshwater aquifers. Dependent communities therefore have to look for a source of water elsewhere or carry out desalination. Both mean higher prices for water because of higher energy costs and higher energy prices on its own.

Sometimes, industries release water back into the environment which has higher than normal temperatures. Known as thermal pollution, this water is dangerous for marine life because of the heat itself and because of lower amounts of dissolved oxygen in hot water. Sometimes, the water contains dissolved agricultural chemicals which can overly fertilize water bodies and cause eutrophication eventually leading to dead water zones that contain no life. Energy is required to cool this water and sufficiently treat it before discharge.

Hydropower plants cause thermal pollution and also flood areas inhabited by people and wildlife.

Biofuels refer to the large scale growing of energy plants which are burnt to provide electricity. Though renewable, this type of energy requires a lot of water used to irrigate the plants in their growth phase. It has a high water demand.

As global temperatures rise because of more and more emissions of greenhouse gases in the atmosphere, the more climate will continue to change.

It is predicted that as droughts become more frequent and longer, more areas will become water scarce and those that already suffer scarcity become arid and semiarid. There will be more competition for water resources between economic sectors, and between human needs and the natural world. This will also occur between communities which will trigger or increase conflict and social upheavals.

Furthermore, the percentage of water withdrawal will spike, while water consumption (water used and not returned to source) increases dramatically. Energy prices will also shoot up.

Now, in the face of all this, there are some remedial measures. One is to recycle and reuse water. Water can be used for multiple purposes when carefully collected. Water recycling is an easy and useful principle. Done at the household level, it could greatly cut the need for fresh supply. Water reuse is already happening in large scale in countries like Israel, where it is separated into household and non-household use like irrigation.

The other is to reduce wastage. Use only the required amounts of water. Water losses from theft and leaks can be rectified and proper action taken.

Increased harvest of rainwater is another solution. Water can be stored in underground or above ground tanks and reservoirs. Water pans and dams that are leaching- proof can be constructed too.

Use of renewable energy in water related processes is good for both climate and human needs. In North Eastern Kenya, boreholes are sunk and operated using power from solar panels mounted nearby. They are colocated.

Shared energy and water facilities is another answer. To lessen the cost of water transport, power plants such as thermal can be located near adequate water supply. Energy generation plants can be located next to water processing plants. They can benefit from their dependencies.

Wastewater plants can produce energy through large scale production of biogas. Already in operation in some places, plants that clean wastewater can produce energy from organic waste. The same energy can be derived from landfills containing municipal waste. This energy can be rewired to power the plant and even provide surplus to be sold to the main grid.

Treated wastewater can also be used in place of freshwater in power generation plants. This lessens demand on freshwater.

Use of renewable energy as a whole to replace non-renewable fossil fuels will dramatically cut greenhouse gas emissions and lower water demand.

Conservation of water sources such as forests is another solution. Forests create a microclimate and increase rainfall. They act as buffers against the worst effects of climate change. Evapotranspiration rates from forests mean more rain. A cooler atmosphere because of forests translate to less demand for water and energy used for air conditioning and cooling.

A very important thing is to address the energy and water sectors jointly. The two are inextricable, so naturally measures in one area will affect the other.

Therefore, policy and legal interventions for energy, water and climate change should be holistic and also address social equity and environmental stability.

Of course, because climate change will as a matter of fact affect water in general, then cutting greenhouse gas emissions is the most consequential solution.

Want to save energy and water? Act on Climate.