Three years ago, governments around the world imposed sweeping curfews and lockdowns to slow the spread of the coronavirus. In Germany and other countries, many employers were now obliged to enable employees to work from home. And a large part has retained that.
Today, for many people, the triumph of home office is one of the few positive side effects of the pandemic. One argument among many: Working from home saves greenhouse gas emissions. But is that really true?
Does a working day in the home office generate fewer greenhouse gas emissions than in the office?
Mostly yes, especially for car commuters.
In Germany, for example, the average distance between home and work is almost 17 kilometers, in the USA it is 25, in Brazil 16 and in China around 8.5 kilometers. But let’s stay in Germany: One average car with a diesel or petrol engine emits about 185 grams (g) of CO2 equivalent (CO2e) per kilometer. Average commuters who habitually sit alone in the car save emissions of 6.3 kilograms (kg) of CO2e per working day in the home office.
Cyclists would have to stay at home 12 times to avoid the same amount of greenhouse gas emissions: According to the European Cyclists’ Federation average Europeans emit just 540 g CO2e over a distance of 34 kilometers – in addition to their basal metabolic rate. Cycling vegetarians or people who only eat regional, seasonal crops need even longer because the transport and cultivation of their food produce fewer greenhouse gases.
For those who habitually use public transport, it basically makes no difference in emissions whether they stay in the home office or drive to the office. The Federal Environment Agency puts the emissions of a public transport bus at 108 grams of CO2e per person and kilometer, but that is an “attribution”. This means: the total emissions (of all buses) are converted to individual units (person-kilometres). The seemingly paradoxical thing about it: when a passenger gets on, it reduces the emissions per passenger kilometer, but their weight has almost no effect on the fuel consumption of the bus.
Isn’t this calculation too simple?
Anyone who reads the above calculations critically will notice that some aspects were not taken into account, but also have an impact on greenhouse gas emissions. So the following questions need to be considered:
- What is the difference between working from home and in the office?
- What equipment needs to be purchased for the home office?
- What role does the purchase and wear and tear of cars, bicycles and public transport play?
- How are offices and homes heated or air-conditioned?
- How is the use of real estate changing?
- How are supply and demand changing in the public transport network?
Do video conferencing and emails offset the saved transport emissions?
As a rule: no.
Most compensate for the physical distance to colleagues in the home office with information technology (see aspect 1). In his bestseller How Bad Are Bananas, British researcher Mike Berners-Lee calculates the “carbon footprint of everything”. Video conferencing, text messaging and email are also included. According to Berners-Lee, of all communication options, video calls on desktop computers require by far the most electricity, namely 50 g CO2e per hour.
Laptops have a much lower carbon footprint than desktop PCs with monitors – in use and in production
To calculate the emissions from a single kilometer by car, you would have to spend almost four hours conferring on a screen. Who uses a laptop even 20 hours. That’s unlikely. And it also plays a completely subordinate role in the overall emissions from Internet use, explains Chris W Preist, who researches the environmental impact of digital technology at the University of Bristol: “Most of the energy is consumed by digital devices – i.e. computers, screens and network devices – regardless of the applications .”
On the one hand, whether you are processing customer data, researching on the Internet or taking part in a video conference is almost irrelevant for power consumption. On the other hand, personal electricity consumption plays a subordinate role in the emissions from global Internet use: “Many estimates that you find in the press are methodologically unreliable and ‘attributive’ instead of taking the change into account. That means: don’t send e-mails, saves almost no energy.”
Is it also worthwhile if new devices have to be purchased?
IT technology is very similar to the per capita emissions from bus and train travel: The utilization of the offer hardly changes the emissions. When it comes to Internet use, it is primarily the existing infrastructure that generates emissions and – which Berners-Lee does not take into account in his figures – aspect number 2: “The manufacture of the devices dominates the emissions,” says Preist.
If you buy a computer to work from home, you have to according to the Öko-Institut around 280 kg CO2e for a laptop, and even 435 kg CO2e for a desktop PC including monitor. In order for such a purchase – including electricity for 2 hours of additional video calls a day – to have a positive climate balance, the average German commuter has to stay at home for 45 (laptop) or 70 days (desktop). With a regulation with 3 days of home office per week, it takes 3.5 or 5.5 months until you write “green” numbers with the investment.
Cyclists, pedestrians and commuters who use public transport hardly reduce their carbon footprint by working from home. If you buy a laptop to work from home three times a week instead of cycling 5 kilometers to the office, it will take around 15 years for the emissions from the purchase to balance out – provided (aspect 3) the bike is available anyway. Its production generates a similar amount of greenhouse gases as that of a desktop PC. However, if you sell your car at the same time, you are definitely in the light green area.
Can companies become greener thanks to home office?
Yes, especially in the long term.
First of all, emissions are shifting to the home office: In addition to electricity consumption, the need for heat or air conditioning at home can also increase (aspect 4). What that means for the climate depends on where heating is more efficient. One thing is clear: Turning down the heating when you’re away saves energy and thus also emissions – at home and in the office. And it’s not about peanuts.
Companies have already started to reduce the number of offices – there is considerable potential for reducing emissions here
In many countries, the heating and air conditioning of real estate accounts for a large part of the ongoing energy requirements of buildings. In Germany, private households turn loudly Environment Agency around five to six times as many kilowatt hours for space heating as for electricity.
A shift in heat emissions does not initially make companies more sustainable. The situation is different if they reduce the available space themselves (aspect 5). actually have according to various polls Many companies have already reduced the number of jobs: instead of giving all employees their own office, they are making a smaller number of temporary jobs available. If they also reduce office space as a result, there is considerable potential for reducing emissions – in the medium term for heating and in the long term even for construction.
Could dynamic effects turn the whole equation upside down?
The change in office space suggests that the future savings from working from home could be even greater than before. It is also possible that more people are doing without their own car and resorting to car sharing or even public transport for sporadic journeys. That would significantly reduce future emissions; according to Berners-Lee, the production of a car generates between 4 and 25 tons of CO2e.
If more employees move to the countryside and therefore travel longer distances to work, emissions could even increase due to more home office
However, there are also effects that have the opposite effect. So shows an ifo studythat already during the pandemic people increasingly moved their places of residence from cities to the countryside. This is often associated with larger living spaces and almost always longer commutes to work. Ifo economist Waldemar Marz argues in a paper, ifo economist Waldemar Marz argues that people could also attach less importance to low fuel consumption if they – supposedly – have to drive less further investigation. In the long term, the short-term reduction in emissions could even turn into an increase.
Working from home can significantly reduce emissions. However, it depends above all on how far away you live from the office and how you travel this distance as a matter of course. In the medium and long term, however, the ability to work from home can lead to behavior that causes emissions to rise again, especially moving to the countryside, where many journeys – not just those to the office – are longer and more frequently made by car become.