Microwaves used in the EU alone emit as much carbon dioxide as nearly seven million cars, according to a new study by The University of Manchester.
Researchers at the University have carried out the first ever comprehensive study of the environmental impacts of microwaves, considering their whole lifecycle from ‘cradle to grave’.
The study found that microwaves emit 7.7 million tonnes of carbon dioxide equivalent per year in the EU – comparable with the annual emissions of 6.8 million cars.
Microwaves across the EU consume an estimated 9.4 terawatts per hour (TWh) of electricity every year, which is equivalent to the electricity generated annually by three large gas power plants.
Microwaves account for the largest percentage of sales of all type of oven in the European Union (EU), with numbers set to reach nearly 135 million by 2020. Despite this, the scale of their impacts on the environment was until now not known.
The study used lifecycle assessments (LCA) to estimate the impacts of microwaves, taking into account their manufacture, use and end-of-life waste management.
Microwaves and the environment
All together, the research team investigated 12 different environmental factors, including climate change, depletion of natural resources and ecological toxicity.
They found 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 the electricity consumed by microwaves that has the biggest impact on the environment, when taking into account its whole lifecycle – from production of fuels to generation of electricity.
In total, microwaves across the EU consume an estimated 9.4 terawatts per hour (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. This is despite the fact that microwaves spend more than 90% of their lifetime being idle, in the stand-by mode.