COVID-19 has taken over the world, forcing billions of people to change their lifestyles overnight. The social and economic toll is great, but there could be a silver lining: Billions of minds around the world are being forced to think differently, paving the way for new solutions to major global problems.

If we’re lucky, this new perspective can help realize the potential of lifestyle change as an avenue towards a just transition to a sustainable society. As shown below, such change is sorely needed because high levels of human development across the globe will require 2–4 more planets than we have at our disposal.

Technology alone is not going to give us a sustainable society. If you toggle through the years in the global footprint network graph above, it becomes clear that the power of progress is used to move countries to the right, not down. Those who were not lucky enough to be born into affluent societies already built by fossil fuels are understandably keen to continue this march to the right.

It’s up to us lucky few who won access to the right of this graph in the lottery of birth to demonstrate that high levels of human development can be sustained on the single planet we have. This will require lifestyle changes that are in some ways comparable to the ones we’re currently forced to undertake, only implemented in a much more orderly and rewarding manner.

About two years ago, I wrote an article about the relative importance of different sustainability options. The conclusion is summarized in the following figure.

The three big slices accounting for 60% of the expected impact all originate from behaviour and lifestyle changes. Let’s take them in ascending order.

Being a health crisis, COVID-19 has focussed a lot of attention on personal health. Those in poorer health are known to be at greater risk, particularly the elderly and those suffering from chronic disease.

Chronic disease is responsible for an unbelievable 90% of the enormous healthcare expenditure of the US. And the primary recommendations given by authorities to lighten this terrible burden are simple healthy lifestyle choices.

Such lifestyle choices not only minimize the great suffering and cost caused by chronic disease, but personal environmental footprint as well. A diet dominated by healthy plant-based foods at the recommended daily calorie intake can greatly reduce environmental impact relative to the standard meat-rich diet eaten in unhealthy excess. In addition, healthy levels of exercise through cycling and walking instead of driving for all shorter trips can bring sizable additional emissions cuts.

As an added bonus, broad application of healthy lifestyle choices can gradually refocus many highly educated minds from fighting a self-imposed chronic disease epidemic to proactively building a sustainable society.

COVID-19 brought remote work into the spotlight almost overnight. Many people are finding out that this can actually be done. At the institute where I work, we recently upgraded to Microsoft Teams, which is a vast improvement over the old Skype for Business. Thus far, the experience has been great with smooth remote meetings and reliable screen sharing. In the not-too-distant future, virtual meetings will become complete VR experiences that, in many ways, exceed the physical status quo.

I have long believed that virtual mobility is a much better avenue for cost-effective emissions reduction from the transport sector than electric or autonomous vehicles. In fact, my estimation of the total economic benefits from remote work amounts to an enormous $18500/year per person. COVID-19 may just allow millions more to realize these huge benefits.

But the biggest potential benefit from virtual mobility is the creation of car-free neighbourhoods and city zones — places built for people instead of cars, where being outside and active is a genuine treat. The speed of this rising trend will obviously be limited by sunk infrastructure investments in the developed world, but I hope that an increased focus on virtual mobility after COVID-19 can make this a bigger focus in developing regions where most infrastructure still needs to be built.

Life efficiency is the ratio of happy life years (product of wellbeing and life expectancy) over ecological footprint. In other words, it measures our ability to convert environmental destruction into happiness and longevity.

As shown below, rich nations generally have low life efficiency as increases in environmental impact outpace gains in happy life years. Thanks to the hedonic treadmill, a Western consumerist lifestyle greatly inflates environmental impact for little gain in happiness. Life expectancy is also constrained by various unhealthy consumer choices.

For perspective, the sustainable ecological footprint is 1.7 hectares/person. With a life efficiency of less than 10 HLY/hectare, rich nations would barely be able to eke out 15 happy life years per citizen in a sustainable world. The only way to fix this is to pursue happiness through creative and meaningful contributions to society instead of the fleeting endorphin highs brought by consumption.

Wholesale changes in the labour market implied by such a shift will certainly take time, but it is already underway as younger generations demand purpose over paychecks. COVID-19 can help accelerate this transition by reminding us about what is really important in life and creating a sense of unity and purpose in the rebuilding effort.

To quantify the potential benefit of the behavioural changes outlined above, I modelled four different lifestyles using the global footprint network’s individual footprint calculator. The calculator is quick and simple to use, and I strongly encourage all readers to take a couple of minutes to complete this test for themselves.

We start with a base case: a family of three living in a 250 square meter house. Their diet includes average amounts of beef, pork, poultry and dairy and they buy average amounts of clothing, gadgets, appliances and furniture. They travel about 15000 km per year in their 40 MPG car, 50% of which are shared trips. Each also clocks up an average annual flight time of 30 hours for business and holiday.

The next case includes healthy lifestyle choices. Beef is reduced to almost zero (only special occasions) and pork, poultry and dairy are used more sparingly. In addition, car miles are reduced to 5000 km/year, displaced by 7500 km/year on public transport and a commitment to walk/cycle for all shorter trips.

In the third case, we add the potential of virtual mobility. Here, the use of car, public transport and air travel are all halved on the assumption of a partial home office and fewer business travels.

Finally, we have the case of life efficiency where two major changes are made. First, the family moves to an ideally located 150 square meter apartment, allowing them to conveniently walk/cycle almost everywhere they need to be. Only 1000 km of car and 1000 km of public transport are included annually. Plane travel is also cut to 8 hours annually as long-distance holidays are displaced by local vacationing. Second, the family commits to happiness through creation instead of consumption. This reduces their purchases of clothing, gadgets, appliances and furniture to little more than the rate at which their existing stuff wears out.

Results are shown below. Recall that the global carrying capacity of planet Earth is 1.7 hectares/person.

The base case shows an ecological footprint that would require well over 4 planets if all people adopted this lifestyle. A CO2 footprint of 12 tons/year is calculated — also about 4x the sustainable limit.

When healthier eating habits and some exercise through walking/cycling as a transport mode are introduced, ecological footprint reduces substantially, mainly due to a halving in the ecological impact of food production. The mobility footprint also declines by about 15%.

This does not tell the whole story though. There are two important effects not included in this calculator: the amount of food consumption and the use of healthcare services. Those born into affluence consume as much as 50% more calories than the recommended daily allowance, which is the reason for our global obesity epidemic. A healthy lifestyle would eliminate this self- and planet-destroying practice. In addition, a broad commitment to healthy lifestyles would eliminate most of the 90% of total healthcare expenditure dedicated to chronic disease. Healthcare represents about 10% of GDP, implying that it consumes a huge amount of resources. The impact of healthy living can therefore be reasonably assumed to be considerably larger than calculated here.

Next, a commitment to virtual mobility halves the ecological and carbon impacts of mobility as physical transportation is partially displaced by virtual alternatives. In addition, the services footprint shrinks by about 25% due to lower use of air travel and public transport. Since transportation is generally quite carbon intensive, this case achieves a larger CO2 reduction than the healthy living case, even though the reduction in ecological footprint is somewhat smaller.

Finally, the potentially very large impact of high life efficiency is shown. The decision to move from a free-standing home in the suburbs to a smaller, ideally located apartment in town strongly reduces the footprint related to shelter and mobility, and mildly reduces the services footprint. In addition, the ability to replace retail therapy with creative expression greatly reduces the goods footprint.

Overall, the life efficiency case reduces ecological and carbon footprints by more than a factor of three relative to the base case. It is still not quite sustainable, but the gap to sustainability is small enough to be bridged by technological progress, despite the continued increase in global population. In fact, demand reduction from increased life efficiency will make the global energy transition significantly easier, faster and cheaper.

Clearly, the positive effect of environmentally intelligent lifestyle change can be tremendous. Such changes can also create a much healthier and more economically stable society. Happiness levels will arguably also see large gains, although this is harder to quantify.

Implementation of such measures depend on a change in culture to move beyond the primitive pursuit of instant pleasure through consumption. There are signs that this transition is already underway with concepts such as the post-growth economy, downshifting, voluntary simplicity and FIRE. In the new post-consumerist culture that is slowly taking shape, high life efficiency will be appropriately valued, while environmentally destructive displays of excess attract public scorn.

Governments can also help via internalization of externalities, not only relating to climate, but to health and mobility as well. In addition, the construction of car-free urban spaces looks to be one of the most socially beneficial investments available, particularly in developing regions.

COVID-19 is shining a bright spotlight on health and virtual mobility, both of which can greatly accelerate these promising trends. From here, increased life efficiency is a natural next step. I sincerely hope that this ongoing crisis will be remembered as the birth of the environmentally intelligent citizen taking great pride in designing a lifestyle that saves the planet, while simultaneously achieving perfect health, financial security and stellar life satisfaction.