Exploring the health benefits of EVs
September 17, 2018
September 17, 2018
Worldwide, there are 1.3 billion vehicles on the road. And in 2018, nearly all of those vehicles are powered by internal combustion engines (ICEs) that burn fossil fuels to create the mechanical energy required to drive them forward.
But not all of the energy trapped in the fuel actually gets used to move the vehicle along the road. In fact, for a typical gas-powered car, only about 17 –21 percent of the energy stored in gasoline is converted to power at the wheels.
Over 60 percent of the fuel’s energy is lost in the internal combustion engine. ICE engines are very inefficient at converting the fuel’s chemical energy to mechanical energy, losing energy to friction, pumping air into and out of the engine and wasted heat.
In comparison, electric vehicles convert between 59 and 62 percent of the electrical energy from the grid to power at the wheels.
Some of the energy lost in the engines of ICE vehicles is converted to sound energy. Petrol heads say that they love the roar of their engine, but would they still love it so much if they realized that this noise was contributing to making their cars less efficient? In comparison, the silent motion of the electric vehicle makes it an urban dweller’s dream, reducing traffic noise pollution and making towns and cities quieter and more pleasant places to live.
Health-impacting airborne pollutants from ICE vehicles
Not only are ICE vehicles less efficient, but the process of burning gas or diesel is also responsible for the emission of a wide range of health-affecting pollutants.
Unborn and new-born children, people with chronic illnesses, and the elderly are most at risk from almost all of their effects. The major pollutants from ICE vehicles are:
- Particulate matter (PM) – These are tiny particles, measuring up to 10 micrometers in size, that can seriously threaten human health because they get deep into the lungs. Particles in diesel vehicle exhaust are a major cause of PM pollution.
- Volatile Organic Compounds (VOCs) – VOCs react with nitrogen oxides to form ground-level ozone, a major ingredient in smog. At ground level, ozone irritates the respiratory system, causing coughing, choking, and reduced lung capacity. They have also been linked to some forms of cancer.
- Nitrogen oxides (NOx) – These pollutants form ground-level ozone and particulate matter. NOx can also lead to lung irritation and make the body more susceptible to respiratory infections like pneumonia and the flu.
- Carbon monoxide (CO) – This poisonous gas is formed when fossil fuels like gasoline are burned, making ICE vehicles a primary cause. When inhaled, CO blocks oxygen from the brain, heart, and other vital organs.
- Greenhouse gases (GHG) – ICE vehicles emit carbon dioxide and other pollutants that contribute to global warming. In fact, tailpipe emissions from ICE vehicles account for over one-fifth of the United States’ total global warming pollution. Global warming is responsible for a wide range of public health risks. It has been linked to more frequent and intense heat waves such as the 2003 heatwave in Europe which caused over 20,000 premature deaths. Other extreme weather events such as flooding, droughts and sea level rises have been made more likely due to global warming and can have devastating impacts, giving rise to spikes of infectious diseases and threatening the lives of millions of people.
- Sulfur dioxide (SO2) – Diesel fuel contains sulfur, creating sulfur dioxide when it’s burned. SO2 can react in the atmosphere to form tiny particulate matter, posing a particular risk to young children and asthma sufferers.
The health benefits of electric vehicles
So, what about electric vehicles? We know that they create zero emissions from the tailpipe, meaning that they’re not emitting any health impacting pollutants* into the local atmosphere, but until our whole grid is powered by zero-emission renewable energies, surely, we’re just displacing where these emissions go?
The short answer is no – a recent study by VUB University in Brussels showed that the entire lifecycle GHG emissions from electric vehicles (including manufacture, transportation, and disposal) are about a quarter less than for ICEs, even when the electricity they’re using comes almost entirely from coal-fired power stations.
The energy mix of the US grid is currently 30 percent coal, 32 percent natural gas (which is much cleaner burning than diesel or gasoline), and 37 percent renewables including nuclear. The proportion of renewable energies powering the electricity grid is expected to grow steadily, and depending on who you ask, could account for between 50 to 80 percent of total electricity generation by 2050. By then, the lifecycle GHG emissions of electric vehicles would be about 85 percent less than for ICE vehicles.
*All vehicles including EVs create some particulate matter from tire and brake wear. However, with EV’s regenerative braking systems, even these emissions are less than for ICE vehicles.
The urban public health benefits of EVs
What’s currently more important from a public health perspective is that those emissions are displaced away from the areas where people live closest to vehicle traffic. This zero-tailpipe emission represents the greatest urban health benefit of EVs.
Cities all over the world, in both developing and developed countries, have in recent years suffered from air pollution levels that surpass international standards and threaten the health and lives of their citizens. The main cause of the degradation in urban air quality? Road transportation by ICE vehicles.
In the UK, air pollution is responsible for 40,000 premature deaths per year. A study found that the health-related costs of diesel vehicles were 20 times greater than for plug-in electric vehicles and that switching a million cars from diesel to electric would save more than £360m ($470m) in health costs from local air pollution per year.
Cities leading the fight to clean their air
Some cities are launching bold plans to solve this serious public health problem, with electric vehicles seen as a central part of the solution. Currently, 20 cities throughout the world dominate EV sales, including Los Angeles, San Francisco, New York and San Jose in the U.S.
A dozen C40 cities have pledged to create emission-free zones, and many have established deadlines to remove or regulate the use of ICE vehicles, as well as committing to plans to move to 100 percent zero-emissions transit buses and taxis.
San Francisco is developing its EV charging network for residents of multi-unit dwellings, recognizing that for widespread EV adoption, these residents need access to convenient charging infrastructure near their homes.
Over the coming years, other cities will be sure to learn from the positive examples that these leading cities set.
If you have responsibility for the vehicle fleet within your organization, then by working to upgrade your vehicles to electric, you have the potential to improve the health of your employees and the citizens that live in the area where you operate. Over a half of all vehicles on the road belong to businesses, so companies and municipalities can make a huge positive impact on our global public health by leading the charge to electric!