People, animals and plants need fresh water to survive, and with a planet that is composed of 70% water, this should not be much of an issue. Unfortunately, most of it is salt water, and not fresh. Fact is around 20% of the planet’s fresh water can be found in the Amazon basin alone, and with drought conditions experienced in many areas of the world, water supply is running short. Now, one particular solution to such a problem is desalination, which is the process of removing salt and other particles from seawater and other waste water. This is most probably a necessary method in case of population increase and drought, but surprisingly, it has also become a very controversial issue, where people seemingly have very strong opposing opinions about its purpose. That is why, on our end, it is important to look at the pros and cons of desalination in order to come up with a well-informed insight about such a technology. In this article, pros and cons of desalination are presented briefly.
Pros of Seawater Desalination (Reverse Osmosis)
1. Effective technique
Reverse osmosis, a method of removing salt from seawater has been proven effective in creating fresh sources of drinking water that can deliver the health benefits people need. When properly designed, desalination plants can then create drinkable water that is of high quality.
2. Water resource conservation
As the planet’s freshwater supply is rather limited, it just makes sense that we should preserve it as much as possible. This would secure more resources to be used where conservation efforts are currently placed, as there is scarcity of water that is available these days.
3. Use of saline water sources (Seawater)
Even if all water is produced through desalination, sea water would provide an almost inexhaustible supply, which means that even in times of drought, people would have sufficient access to fresh water supply needed for growing crops, for daily living and for a lot of other needs. Simply put, it brings an end to water crisis.
4. Unlimited supply of water
One huge problem with many proposed solutions to the ever-increasing water demand is that they heavily rely on uncontrollable factors. For example, more water reservoirs would presuppose that they need rain or snowfall to be filled up. However, desalination does not rely on anything aside from the ocean. With concerns surrounding the melting of the polar ice caps and the rise of the sea levels, nobody would be worried about the ocean disappearing anytime soon.
5. Developed technology
Such a method of desalination is backed up by scientific data and is highly understood. The technology used is also reliable that it allows for high-quality water, which means that using such method should allow for great results and could help eliminate water shortage crisis that the world might face in the future.
6. Safety of desalination plants
Desalination plants are located away from large residential areas. Though there are large facilities, they are located in industrial zones, so they would not put residential areas at risk. People just have to put a plan in place for the location of desalination plants to make such a technology safer in the long term. What’s more, just a single desalination plant will be able to supply more than 500 million litres of water that would be drinkable. With this incredible amount of water, we could change the way we get water.
Cons of Seawater Desalination (Reverse Osmosis)
1. High capital cost
Building desalination plants is not always feasible for a country or a community, with construction costs that are high enough to prevent the development of the technology, as many people just cannot afford the initial price tag—and there are not enough returns to justify the investments made.
2. High energy requirement
Electricity and energy is required to produce water from desalination than any other water supply or demand-management options around the globe, which implies a concern of further dependence on fossil fuels. Nevertheless, it should be noted that the use of fossil fuels has been reduced in many facilities worldwide by using wave, wind and solar energy to power facilities up.
3. High operational cost
For the average desalination plant these days, it takes 2 kilowatt hours of energy in order to produce 1 cubic meter of fresh water. Though this would translate to a cost of just under 2 dollars on a lot of power grids, the real production cost comes from the expenditure of fossil fuels that are needed to create electricity for its process.
4. Excessive brine production
In creating fresh water out of seawater, salt in the water is needed to be removed—a process that produces brine that is so rich in salt that it can contaminate any environment where it is placed. The brine is very strong that it can kill wildlife and vegetation should it comes into contact with them. Aside from this, there are usually anti-scaling agents and chlorine-removing chemicals in the brine as well.
5. Release of greenhouse gasses
Opponents of desalination argue their concern that its plants could produce high amounts of greenhouse gas emissions, which means that that the process of removing salt from seawater can be very harmful to the environment and can have a negative impact on the air that we breathe.
On January 8, 2015, the Newport Mesa Tea Party hosted a debate by leading experts on the pros and cons of salt water desalination in Huntington Beach. This debate session is very interesting and must listen for us all.
By weighing the pros and cons that are listed above, each of us will be able to come together to make a final decision whether the costs of desalination are worth the gains that we might see.