Microwaves ‘could be as bad for the environment as cars’
Use of microwave ovens in households across the European Union member states is responsible for a level of carbon dioxide emissions equivalent to nearly seven million cars, and new regulations are needed to address their impact on the environment, according to a new study.
Despite microwaves accounting for the largest percentage of sales of all type of ovens in the EU, with numbers set to reach nearly 135 million by 2020, researchers at the University of Manchester who have carried out what they claim is the first ever comprehensive ‘cradle to grave’ analysis of environmental impacts say little has been done before now to assess this aspect of their use.
The project, reported in the journal Science of the Total Environment, used lifecycle assessment that takes into account manufacture, use and end-of-life waste management. Based on 12 different environmental factors including climate change, depletion of natural resources and ecological toxicity, researchers estimate that ovens in the EU emit 7.7 million tonnes of carbon dioxide, a similar annual amount to 6.8 million cars.
Although the main ‘hotspots’ are raw materials, the manufacturing process and end-of-life waste management, it is electricity consumption that has the biggest impact on the environment, from production of fuels to generation of electricity.
The average microwave uses 573kWh of energy over its eight-year lifespan, despite that fact that it spends more than 90 per cent of its time in standby mode. In total, ovens across the EU consume an estimated 9.4TWh every year, similar to the output of three large gas-powered electricity plants.
Waste is another major problem. Low cost and ease of manufacture means that consumers are throwing away more electrical and electronic equipment like microwaves than ever before. In 2005, across the EU, 184,000 tonnes of EE waste was generated from discarded microwaves. By 2025 this is estimated to rise to 195,000 tonnes.
Lifespan is getting shorter too, having fallen from 10-15 years in the late 1990s to between six and eight years today, something that is attributed in part to consumers buying new appliances before the existing ones reach the end of their useful life.
The study’s authors also suggest that efforts to reduce consumption should focus on improving consumer awareness and behaviour to use appliances more efficiently, for example by adjusting cooking time.
According to Dr Alejandro Gallego-Schmid from Manchester’s School of Chemical Engineering & Analytical Science, existing regulation are not sufficient to reduce the environmental impacts of microwaves and recommends that the EU should develop specific rules that target their design.
“Given that microwaves account for the largest percentage of sales of all type of ovens in the EU, it is increasingly important to start addressing their impact on resource use and end-of-life waste,” he said.