- 19th April 2023
- Clean Cooking
By Prof Matthew Leach
Simon Batchelor’s blog on the Global Cooksafe Coalition highlights that concern about safe and sustainable cooking is an issue for OECD kitchens as well as those in LMIC. Here we look more closely at the fuels and stoves used in the US and Europe, how we got here and where things are headed. Why is this relevant to MECS? Because while almost everyone in the OECD already has access to higher tier cooking solutions there are major changes afoot, driven by concerns about indoor air pollution and climate emissions, and this has the potential to transform global supply chains.
The fuels and stove types used for cooking in Europe and the USA have undergone significant changes. Before the second World war the most common fuel used for cooking and heating was coal. By 1940 75% of homes in Britain were connected to electricity, and increasing numbers were connected to the gas network. Gas and electric stoves were both available, but coal cooking remained much cheaper (half the cost of gas and one quarter that of electricity by 1938). The gas and electricity industries competed for customers and policy support, each claiming convenience, and electricity advocates promoting safety and cleanliness. Competition started in lighting and moved to heating and cooking. Note that ‘gas’ in this period was ‘Town’ or coal gas, manufactured as a lighting and cooking fuel, relatively clean burning but poisonous if it leaks.
The 1952 Great Smog of London killed many thousands of people through health effects of air pollution, mainly from coal burning. This led to the Clean Air Act 1956, development of ‘smokeless’ solid fuels and establishment of ‘smoke controlled areas’. But coal prices were also rising, and in the 1960s Britain made significant natural gas discoveries. From 1968 the government directed a nationwide transition from town to natural gas, requiring change to the burners for every device, converting some 40 million appliances in just 8 years. Natural gas quickly became a popular fuel for cooking due to its convenience, affordability, and perceived cleanliness.
Electric stoves also started to become more popular in the 1960s and 1970s. These stoves were initially expensive, but their price dropped as production methods improved. Gas stoves have typically been preferred by chefs and cooking enthusiasts because of their precise temperature control and quick heating times. However, advances in electric stove technology, such as induction cooking, are closing the performance gap. Induction cooking uses electromagnetism to heat the cookware directly, rather than heating the air around it, resulting in faster heating times and precise temperature control. The average energy use in the kitchen in the UK halved between 1970 and 2010, mainly due to fan driven ovens (more efficient than static ovens), the introduction of microwaves (and the accompanying sale of pre-cooked food), and a slight change in the way the data was gathered.
In 2022, the most common fuels used for cooking in Europe were electricity (45%), gas (39%), and solid fuels (16%), with similar shares in the United States. So, electricity has overtaken gas cooking. This is partly explained by practical constraints on fuel availability: the network of natural gas pipes doesn’t reach more than 25% of US households, and its availability varies across countries in Europe, with only 40% connected in the EU, whilst most OECD countries have full electricity access. In some countries, such as France and Italy, propane gas (aka LPG) is also widely used, as it is in rural areas in the USA, not connected to the gas network. Wood-burning stoves are also popular in rural areas, particularly in Scandinavia, and are often used for heating as well as cooking.
So electric stoves are now the most common type of stove used for cooking in both Europe and the USA. Even sweeter music to MECS’ ears, electric pressure cookers (EPC) are becoming increasingly popular. In 2021, the global market for EPCs was valued at $4.5 billion, and it is expected to grow to $7.4 billion by 2028. EPCs are most prevalent in the United States (estimated to be in 40% of households), followed by China, Japan, and South Korea. In Europe, EPCs are in around 20% of households, most common in the United Kingdom, followed by Germany, France, and Italy. They are mainly a stacked appliance for the cooking of some meals and dishes alongside other equipment.
So as of now, some 50% of households primarily use an electric stove and more than 40% are primarily cooking with natural gas or LPG. (Most gas users also have electrical appliances). Modern energy cooking is already the norm, so isn’t that “job done” in OECD countries from an air pollution point of view? Not quite. Having got past the more visible pollutants of solid fuels we now find that the popularity of gas cooking is declining in both Europe and the United States, due to concerns about air pollution and the health risks associated with burning gas in the home, as well as climate change.
A study published in Environmental Health Perspectives in 2014 found that cooking with gas is a significant source of indoor air pollution, with gas stoves emitting high levels of nitrogen dioxide, carbon monoxide, and formaldehyde. These pollutants can increase the risk of respiratory and cardiovascular diseases, as well as other health problems. Another study published in Environmental Research in 2017 found that exposure to gas stove emissions was associated with a higher risk of asthma symptoms in children. Gas leaks can also be significant: a study published in Environmental Science and Technology in 2022 attributed significant levels of Volatile Organic Compounds to leakage of unburned natural gas inside homes. The gases found are designated as hazardous air pollutants and are associated with increased cancer rates.
Concerns are not only about physical well-being: a study published in Epidemiology found that exposure to gas stove emissions was associated with a (small) adverse effect on cognitive development in infants.
Besides indoor air pollution, combustion of natural gas or propane from fossil sources releases carbon dioxide, a greenhouse gas that contributes to climate change. While electric stoves also contribute to greenhouse gas emissions based on the energy sources used to generate the electricity, the shift towards renewable electricity sources means that electric cooking is becoming increasingly sustainable.
These findings have started to catch public and media attention: eg the UK’s Guardian headline: “Your Gas Stove Is Polluting Your Own Home. Go Electric.” In the US the depth of public concern is exemplified by legal action, with a class action just started against LG Electronic, a supplier of gas stoves, claiming the asthma risk posed is “avoidable” through better design, and that manufacturers should disclose the risk of pollutants to consumers, who might then choose an electric stove.
The move away from gas and towards electric cooking is also being driven by government regulations and incentives. In California, new regulations require all new homes to have electric stoves instead of gas stoves. Other states and countries are also exploring similar regulations to promote electric cooking: in Massachusetts, there is a $500 rebate offered for swapping a natural gas or LPG stove for induction.
The European Union has set regulations to limit the amount of pollution from gas cooking appliances. The specific rules and laws vary by country, but generally, they fall under the EU’s Energy Efficiency Directive (EED) and the Ecodesign Directive. The former sets requirements for gas cooking appliances to be more energy-efficient and to emit less pollution. The latter sets limits on emissions of NOx, CO, and PM from gas cooking appliances, and requires manufacturers to meet these standards in order to sell their products in the EU.
In conclusion, there is a move away from gas stoves being driven by concerns about air pollution, the climate crisis, and the health risks associated with gas stoves. As more people become aware of these risks, it is likely that the move away from gas stoves will continue to gain momentum. As technology continues to advance, electric cooking is becoming increasingly efficient, affordable, and sustainable, making it an attractive alternative to gas cooking.