This is the first blog in a series on the intersection and interdependence of energy and water.
As global warming heats up, water scarcity is the latest hot topic in climate and energy conversations (no puns intended). The first five months of the year saw record high temperatures and widespread drought affecting large swathes of the United States, most notably California, which is experiencing dangerously low precipitation levels, prompting Governor Jerry Brown to call for statewide water restrictions.
As a result, we are witnessing a clear example of how drought can impact industry, agriculture, and individuals on a large scale. What is not as obvious is how the current push for renewable energy is implicitly tied to improving drought conditions in areas like California. Unlike fossil fuel-based electricity production—one of the largest consumers of water in the US at 49% total water use–renewables use little to no water and could be the answer to our current water woes—not to mention their role in reducing or even reversing the climate change responsible for global warming.
To understand how renewable energy helps with the water crisis, one must first understand why traditional energy generation is water intensive. Water is essential in all phases of fossil fuel energy production, and often results in the contamination of fresh water sources. For example:
Over 40% of fresh water withdrawals in the US are used to cool power plants
Natural gas extraction (hydraulic fracturing, or fracking) and refinement uses 361 gallons of water per megawatt-hour (MWh)
A coal powered plant uses 427 gallons of water per MWh
In addition to diverting fresh water away from other pressing human needs, fossil fuel electricity production has a massive effect on our water supply. Enormous amounts of water are required to keep power plants cool and running safely. When this water is released from the plant after treatment, it is much warmer than local ecosystems can tolerate. This thermal pollution has a negative impact on the species living in the water that cannot withstand the higher temperatures, decreasing biodiversity.
Coal mining and combustion expose water supply to dangerous toxins including lead, mercury, and arsenic. These coal plants also create acid rain when combustion releases carbon dioxide and other greenhouse gases into the atmosphere. Additionally, drilling for fracking exposes groundwater supplies to fracking fluid and chemicals that contaminate the water table, disturb ecosystems, and negatively impact human health.
Our current electricity system is dependent on water, and with climate change bringing further drought, paired with increased energy demands in already suffering areas, we can’t spare a drop. Using fossil fuels for energy puts the U.S. at risk for natural resource depletion as energy demand increases and water levels decrease. For example, when a power plant is deprived of water to cool the plant it must cut back or stop energy production altogether. And, as described above, the processes used to refine these fuels threaten not only availability of fresh water, but also its quality.
By comparison, wind and solar power are considered “No-Water” energy options. Investing in these sources of energy will prove to be a necessary long-term solution for companies that wish to secure their resource future. The acquisition of renewable energy in the form of power purchase agreements (PPAs), for example, can guarantee a company clean energy for years to come. Earlier this year, the town of Georgetown, Texas, signed a solar PPA with SunEdison for 150 megawatts. When citing the reasons behind the decision, town leaders noted that the municipal utility would significantly decrease their water usage.
Corporate investment in renewables is also good for the general public, as a transition to a higher percentage of renewable energy in the U.S. energy portfolio will safeguard groundwater supplies from further depletion and contamination. As prices for wind and solar drop, it is becoming more and more evident that these clean, no-water sources provide the best possible outlook for realistically tackling current energy needs, as well as maintaining water security for generations to come.
To continue to blog 2, click here.