We can stop global warming by using fewer microwave ovens, says University of Manchester

University of Manchester

Microwaves usage in just the European Alone is cooking the planet, according to a new study by The University of Manchester. They determined that by estimating all of the energy that goes into the entire life cycle; ill-defined virtual emissions. And those virtual emissions, 7.7 million tons of carbon dioxide, are as much as 6.8 million cars, the authors write in Science of the Total Environment.

From cradle to grave, they estimate 9.4 terawatt-hours (TWh) of electricity every year for microwave ovens. That is equivalent to the annual electricity generated by three large gas power plants. The study used life cycle assessment (LCA) to estimate the impacts of microwaves, taking into account their manufacture, use and end-of-life waste management. Altogether, the research team investigated 12 different environmental factors, including climate change, depletion of natural resources and ecological toxicity. They found, for example, that the microwaves used across the EU emit 7.7 million tonnes of carbon dioxide equivalent per year. This is equivalent to the annual emission of 6.8 million cars. The research shows that the main environmental ‘hotspots’ are materials used to manufacture the microwaves, the manufacturing process and end-of-life waste management. For example, the manufacturing process alone contributes more than 20% to depletion of natural resources and to climate change.

However, it is electricity consumption by microwaves that has the biggest impact on the environment, taking into account its whole life cycle, from production of fuels to generation of electricity. In total, microwaves across the EU consume an estimated 9.4 terawatt-hours (TWh) of electricity every year. This is equivalent to the annual electricity generation by three large gas power plants.

The study found that, on average, an individual microwave uses 573 kilowatt hour (kWh) of electricity over its lifetime of eight years. That is equivalent to the electricity consumed by a 7 watt LED light bulb, left on continuously for almost nine years. The study’s authors suggest that efforts to reduce consumption should focus on improving consumer awareness and behaviour to use appliances more efficiently. And to throw them out a lot less. They estimate that by 2025 there will be 195,000 tons, 16 million individual units, being sent to landfills.

'Environmental assessment of microwaves and the effect of European energy efficiency and waste management legislation' Alejandro Gallego-Schmid, Joan Manuel F.Mendoza, Adisa Azapagic, Science of the Total Environment DOI: 10.1016/j.scitotenv.2017.11.064