Microwaves release millions and millions of tons of carbon monoxide into the environment every year, a new study has shown.
In the European Union alone, microwaves are responsible for some 7.7 million tons of carbon monoxide emissions each year, which is equivalent to the amount released by about 6.8 million cars.
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While microwaves are one of the most common household kitchen appliances, their impact on the environment wasn't well understood prior to this study, according to a recent news release from the University of Manchester.
"It is electricity consumption by microwaves that has the biggest impact on the environment," the study's authors said, according to The Guardian.
"Efforts to reduce consumption should focus on improving consumer awareness and behavior to use appliances more efficiently. For example, electricity consumption by microwaves can be reduced by adjusting the time of cooking to the type of food."
Looking at 12 different environmental factors including depletion of natural resources, ecological toxicity and climate change, researchers used life cycle assessment to estimate the impact of microwaves.
Microwaves negative environmental footprint peaks during their manufacturing and when they are thrown away. According to the research, the manufacturing process alone "contributes more than 20 percent to depletion of natural resources and to climate change."
Across the European Union, the study estimates that microwaves consume 9.4 terawatt-hours (TWh) of electricity every year. That's roughly the same as the electricity generated by three large gas power plants.
"Given that microwaves account for the largest percentage of sales of all types of oven in the EU, it is increasingly important to start addressing their impact on resource use and end-of-life waste," Dr. Alejandro Gallego-Schmid, an author of the study from the University of Manchester's School of Chemical Engineering and Analytical Science, said, according to The Independent.
However, other experts have downplayed the findings, while still admitting that microwaves cause environmental damage.
"To say microwave ovens are 'as bad for the environment as cars' is an apples to oranges comparison, because one (the microwaves) is for a full life-cycle assessment and the other (cars) is just their direct emissions from being driven," David Reay, Professor of Carbon Management at the University of Edinburgh said, according to The Telegraph.
"Yes, there are a lot of microwaves, and yes they use electricity. But their emissions are dwarfed by those from cars – there are around 30 million cars in the UK alone and these emit way more than all the emission from microwaves in the EU."
Although cars may continue to be a bigger environmental problem than microwaves, the researchers pointed to an alarming trend among consumers. Considering production and disposal of microwaves have such a negative effect, it is worrisome that consumers are keeping their appliances for a shorter and shorter period of time.
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The average life cycle of a microwave has decreased significantly, from about 10 to 15 years in the late nineties to just six to eight years today.
"Consumers now tend to buy new appliances before the existing ones reach the end of their useful life," Gallego-Schmid explained.
"As a result, discarded electrical equipment, such as microwaves, is one of the fastest growing waste streams worldwide."
The study suggests consumers should be made more aware of the environmental impact of microwaves, while also being informed on how to use the appliances in the most energy efficient way. At the same time, the study warns that current government regulations won't be enough to address the problem.
But microwaves and cars are just one of many factors causing severe effects on the global environment. The ballooning impact of human activity on the climate has been a topic of debate among politicians, environmentalists and news pundits.
A study published at the end of last year also revealed that worst-case predictions regarding the effects of global warming are the most likely to be true.
