Water is considering one of the most important resources to support human live. We can’t live without it. When I was young, I always help my grandmother do house chores such as wash dishes, but with the advancement of technology, we now have dishwasher that can help us wash dishes more efficiently. However, my grandmother still insist on hand washing because she believes that hand washing is more convenient and it can conserve more water. Therefore, in this post, I will argue that dishwashers can conserve more water, save money, and save more time than hand washing. Moreover, I will use the example in my house to calculate the amount of water saving from dishwasher than hand washing in one year.
Water plays a vital role in our daily life, and we need it every single day. Not only for doing house chores such as washing cloth, taking shower, and brushing teeth, but also for our own body. 70% of our body is composed of water, and we need to consume water in order to maintain our basic function. I realized that water might seem as a affluent resources; however, the total amount of available water for human used is actually fewer than we think. According to EPA (Environmental Protection Agency), “less than one percent of water is available for human.” The rest of the water is inaccessible for human such as salt water in the ocean, or fresh water frozen in the polar ice caps. Hence, we need to take action to conserve water.
In the aspect of conserving water, it is very common for people to pre-washing the dishes before putting them into the dishwasher because in some degree, it just feels a lot cleaner, and I admit that it is something hard for people to let go the thought. Of course, we need to scrap off the food before putting into the dishwasher, but in fact, it is unnecessary to pre-rinsing. According to Consumer Reports, pre-rinsing dishes waste more than 6000 gallons of water per household each year.
My method is to estimate how many water usage of hand washing per year, and then compared to the water usage of dishwasher. To start, in my house, we often use running water to wash our dishes, and the estimation is roughly about 2.2 gallons per load. (I measure how many water we need to complete cleaning for each time)
- If we are using hand washing, we need to wash dishes three times a day because we will wash dishes right after we finished the meal:
Every day use: \(2.2 gallons\times 3 =6.6 gallons\)
One year for using hand washing: \(6.6 gallons\times 365 days= 2409 gallons/ days\)
2. On the other hand, if we change to dishwasher with standard model: The usage of dishwasher is 5.5 gallons per load.
One year for using dishwasher:\(5.5gallons\times 365 days\approx 2008 gallons\)
3. Moreover, if we using the conserving model: The usage of dishwasher is 3 gallons per load
One year for using dishwasher:\( 3 gallons\times 365 days = 1095 gallons\)
As a result, we can save approximately 1300 gallons of water per year. The more dishes we wash by hands, the more we can waste.
When it comes to the debate of saving money on hand washing or using a dishwasher, the result is hard to precisely being compared, because there are too many factors to consider. However, we still can get a simple idea of how dishwasher compete with hand washing method in the area of energy, money, and time.
First, we assume that the dishwasher runs by electricity, and we used 2.5 kilowatt- hours (kWh) of energy for 12 place settings in hand washing, and compared to dishwasher with only 1.5 kWh to wash the same amount of dishes. Additionally, the cost is 12 cents per kWh in United States, according to Ovo energy. Hence, the total amount of money for using a dishwasher is around 66 dollars per year; in contrast, it costs 109 dollars each year for hand washing.
Many people assume that hand washing is less expensive, but as I mention above, this is not the case. Moreover, hand washing also requires both hot and cold water, which involved the cost of electricity to heat water and the cost of water itself, let alone we usually wash three times a day, but only wash once when we are using the dishwasher because we use the dishwasher when it is fully loaded. In addition, the bottom line for the cost to heat a gallon of water is about 1.5 cents in average. Continue with the data that I present above, it costs additional 36 dollars while using hot water to washing dishes.
Last, many people believe that dishwasher is not worth it enough because it only save little or no time at all. According to the result from a study conducted by Bonn University in 2011, 69% of participants purchase the dishwasher because of its timesaving advantage. Instead of spending time scarping off the leftover food, scrubbing, and rinsing the dishes by ourself, we can use the time more wisely such as writing one extra question for homework. Admittedly, dishwashers also have its own drawback such as it is expensive to buy at the first time, and the problem of needed to be repaired. However, I believe that dishwasher can save more for the long run and it can also protect the environment by reducing air pollution and decreasing the greenhouse gases caused by burning fossil fuels.
All in all, thank you for following along with me through our discussion of how to conserve water. As a result, we can see many unexpected benefit by using a dishwasher. Although dishwasher is prevalent, there are still many people insist on hand washing. So after reading my post, I hope people can also find the benefit of using dishwasher. Not only does the dishwasher save water but it also can help us pare down expenses. Furthermore, it can make our dishes cleaner, and save more time and energy. So we can let the dishwasher help us clean while we can do something else at the same time. I have realized that there are many different methods to conserve water, but changing from hand washing to dishwasher is one of the simplest ways. We, as human, can protect the world and environment together, and this small and simple change can cause significant impact on all human being.
- Daily health post, 2015. “Here’s Why Washing Your Dishes By Hand Is Less Clean And Efficient Than You Think”
- Rodale wellness, 2009. “This or That: Dishwasher v.s. Hand-Washing”
- Ovo energy. “Average electricity prices around the world: $/kWh”
- Office of energy efficiency and renewable energy. “Energy Cost Calculator for Electric and Gas Water Heater”
- The telegraph, 2014. “Dishwasher vs washing up: which is cheaper?”
- EPA “how we use water.”
- The Christian Science, 2011. “Dishwasher vs. Hand-Washing: Which is Cheaper?”