David Mytton

The environmental impact of buying a new laptop – comparing the MacBook Air and Surface Laptop

Published (updated: ) in Environment, IT Energy.

The environmental impact of buying a new laptop – comparing the MacBook Air and Surface Laptop

The MacBook Air has been my favourite Apple laptop for a long time. It was originally introduced in 2008 and after using an iMac for several years, I purchased my first Air in 2010.

I thought the Air + Cinema Display combo was the ultimate setup that allowed me to code on a big display but still travel with a lightweight computer. I’ve tried to switch to iPad many times but still come back to macOS. It’s a shame that Apple no longer makes reasonably priced displays.

Since then, I’ve had a brief stint with a MacBook Pro so that I could have a retina display, but as soon as the MacBook Air received this upgrade in 2018, I switched back. I was particularly glad to leave the touch bar behind!

The environmental impact of consumer behaviour has become a big issue in recent years and companies are starting to take notice. However, I’ve found that a big challenge in purchasing sustainable products is the lack of reliable data. There are a lot of claims out there: recycled, sustainable, green, low-carbon. The problem is determining what this means and whether or not it is just greenwashing.

The tech industry is the largest purchaser of renewable energy. What this means for data center electricity usage is complex, but it is a good sign that companies feel they need to compete on this measure. This means that as you use services from the likes of Apple, Google and Microsoft, you are automatically making the more sustainable choice even though you have not had to do anything specific.

Environmental impact of physical products

Electricity can be generated from 100% renewables but reducing the environmental impact of physical products is more challenging.

The most sustainable thing you can do is to not buy something in the first place. Reducing demand is an important behaviour change but I do not think this is going to have sufficient impact. Too few consumers decide to buy based on sustainability (either because they can’t afford it, or don’t care) and so this is a problem that needs to be mostly addressed on the supply-side.

For some time, Apple has been publishing environmental report cards for all of their products. Indeed, they have lifecycle assessments for all of their products going back for the last 10 years. As Apple just released their new, 2020 MacBook Air I wanted to see how things have been improving.

Carbon footprint of a MacBook Air

Have Apple improved the environmental footprint of the MacBook Air from when I purchased my first one in 2010? Yes.

13″ MacBook Air 201013″ MacBook Air 201713″ MacBook Air 201813″ MacBook Air 2020
330 kg CO2e339 kg CO2e176 kg CO2e174 kg CO2e

The Woodland Trust estimates that each person in the UK is responsible for 5.5tCO2 each year. Note that this excludes flights, imports and other greenhouse gases, so we need to double it to make it more realistic on a CO2e basis. This means that if you purchase the 13″ MacBook Air, it is responsible for 1.58% of your footprint for that year.

Generally people do not buy a new laptop every year so this needs to be spread over its lifetime. Apple uses 4 years in its lifecycle analysis (noting that laptops often last much longer and are passed on/sold). Applying that calculation means 4 years of 11tCO2e = 44tCO2e, of which 0.174t is your 2020 MacBook Air, so that would be 0.40% of your 4-year footprint.

Donating £100 to the Woodland Trust helps them to manage woodland that can absorb 4tCO2. Offsetting your 2020 MacBook Air purchase would therefore cost £4.25.

You may note that there is a sudden drop from 2017 to 2018. The 2018 model was the first one to be made of 100% aluminium. Does the switch to recycled aluminium account for all of the 48% drop in carbon emissions? Hard to say without more data.

Aside from the difference in material source, another difference is that as of 2018, the production process used renewable electricity. How much isn’t stated but Apple says:

Suppliers for the 13-inch MacBook Air with Retina display reduced manufacturing emissions by 1 kg CO2e per unit due to Apple’s Supplier Clean Energy Program.

13″ MacBook Air 2018 report card.

And in the 2020 report this has been changed to:

All 13-inch MacBook Air with Retina display final assembly suppliers are transitioning to 100 percent renewable energy for Apple production.

13″ MacBook Air 2020 report card.

This is the Supplier Clean Energy Program which Apple describes as a major part of its carbon footprint:

Since the electricity used to make our products is the largest contributor to our overall carbon footprint, we’re helping our suppliers become more energy efficient and transition to new renewable energy sources. As part of this program, Apple and our suppliers are working to generate and procure more than 4 gigawatts of new renewable energy worldwide by 2020. This goal represents approximately one-third of our current manufacturing carbon footprint.

That program started in 2015 so what about the new MacBook Air model from that year? Its footprint was actually higher at 480kgCO2e. Perhaps the switch to renewable energy is much more gradual, so the effects had not yet impacted the supply chain. Or perhaps it is the switch to recycled materials that has made the most difference.

What makes up the carbon footprint?

Apple provides reports on a number of other metrics which are worth comparing.

Where are the emissions located?

13″ MacBook Air 201013″ MacBook Air 201713″ MacBook Air 201813″ MacBook Air 2020
Production60%83%77%77%
Transport7%3%17%7%
Use32%13%6%15%
Recycling1%1%<1%<1%

Without the actual numbers behind these %s it is difficult to analyse the change over time. However, it is easy to see that the production makes up the majority of the overall carbon footprint. The key message is that you should avoid buying anything new unless you really have to.

How efficient is the MacBook Air

Efficiency is relevant to the usage portion of the environmental footprint. This is a really important factor when considering energy usage.

MacBook Air power consumption

This compares the 230V power consumption. The figures are slightly different for 100V and 115V but to keep the table small, I picked 230V because I’m in the UK.

13″ MacBook Air 201013″ MacBook Air 201713″ MacBook Air 201813″ MacBook Air 2020
Off0.29W0.27W0.05W0.04W
Sleep0.92W0.93W0.25W0.30W
Idle, display on10.2W4.24W3.11W3.62W
Power adapter efficiency86.4%87.6%91.8%91.8%

Comparing 2010 to 2020, efficiency has improved by 64.7%. This is quite significant when you consider how many laptops Apple sells.

On an individual basis, it is difficult to calculate what this actually means because non-idle usage will differ for each user. “Idle, display on” is the minimum amount of power that will be used but this may be significantly higher depending on what you’re doing with the laptop. The power adapter that comes with the current MacBook Air is rated at 30W so the maximum power usage could be up to x10 higher than this table suggests. That is probably a rare scenario though.

This variability is included in Apple’s % breakdown but the absolute numbers are not provided. Apple says:

To model customer use, we measure the power consumed by a product while it is running in a simulated scenario. Daily usage patterns are specific to each product and are a mixture of actual and modelled customer use data. For the purposes of our assessment, years of use, which are based on first owners, are modelled to be four years for macOS and tvOS devices and three years for iOS and watchOS devices. Most Apple products last longer and are often passed along, resold or returned to Apple by the first owner for others to use.

Apple Environmental FAQ.

What is notable is that you should at least switch your laptop to sleep mode, and ideally turn it off when not in use.

We can work out what the minimum electricity usage is across the 4 year lifetime by making a few assumptions. If we say that a MacBook Air is in sleep mode for 16 hours a day and idle, display on for 8 hours, then over 4 years it will use the following amount of electricity (no adjustment for the adapter efficiency):

13″ MacBook Air 201013″ MacBook Air 201713″ MacBook Air 201813″ MacBook Air 2020
Sleep21,491W21,725W5,840W7,008W
Idle119,136W49,523W36,325W42,282W
Total140,627Wh71,248Wh42,165Wh49,290Wh
Total140.6kWh71.2kWh42.2kWh49.3kWh
Cost£20.48£10.37£6.14£7.18

The cost is based on looking at my latest electricity bill where 1 kWh = £0.1456. Obviously, a laptop would be in use, not idle for 8 hours per day, but this gives a useful baseline to understand what these efficiency numbers mean in terms of £.

Environmental comparison of the MacBook Air and Microsoft Surface

Microsoft is doing some great work with their Surface line of computers. I have had to have the keyboard replaced on my 2018 MacBook Air twice and whilst it was in the store for repair, I used a Microsoft Surface Laptop 3. The hardware is really nicely designed and Windows has come a long way since Vista, which is what made me to switch to Mac.

Microsoft has made some significant environmental commitments, not least its Jan 2020 announcement to become carbon-negative by 2030. They also publish environmental reports for their hardware products.

Carbon footprint of a Microsoft Surface

13.5″ Surface Laptop13.5″ Surface Laptop 213.5″ Surface Laptop 3
152 kg CO2e152 kg CO2e177.8 kg CO2e

The Surface Laptop and Surface Laptop 2 both have 13.5″ displays but the Laptop 3 comes in 13.5″ and 15″. Unfortunately, the environmental report seems to only provide figures for the 15″ Surface Laptop 3 despite have two separate documents for both screen sizes. The figures are the same in both documents, so this may be an error. Other figures are different in each report so I have used the numbers from the 13.5″ report where possible in order to compare with the 13″ MacBook Air.

Surface Laptop power consumption

13.5″ Surface Laptop13.5″ Surface Laptop 213.5″ Surface Laptop 3
Off0.21W0.21W0.23W
Sleep0.45W0.45W0.46W
Idle4.5W4.5W4.76W

Environmental comparison of the MacBook Air and Microsoft Surface

13.5″ MacBook Air 201813.5″ MacBook Air 202013.5″ Surface Laptop 213.5″ Surface Laptop 3
Carbon Footprint176 kg CO2e174 kg CO2e152 kg CO2e177.8 kg CO2e
Off0.05W0.04W0.21W0.23W
Sleep0.25W0.30W0.45W0.46W
Idle3.11W3.62W4.5W4.76W

Based on this comparison, the Apple MacBook Air is a more environmentally friendly laptop. It has a slightly smaller CO2e footprint and better energy efficiency.

Environmental comparison of the MacBook Pro and Microsoft Surface

You might argue that the MacBook Air is not a fair comparison with the Surface Laptop, which has a higher spec than the Air. I have compared them here because I consider the form factor to be equivalents – they are both notebook laptops. You could just as easily say the MacBook Air is more like the Surface Pro lineup, or even that the Surface Pro is more like the iPad Pro. Unfortunately, the lack of a direct equivalence makes the comparison more difficult.

Just to ensure a fair comparison, here is the same Surface Laptop comparison against the MacBook Pro.

13″ MacBook Pro Mid 201913″ MacBook Pro Late 201913.5″ Surface Laptop 213.5″ Surface Laptop 3
Carbon Footprint222 kg CO2e210 kg CO2e152 kg CO2e177.8 kg CO2e
Off0.07W0.06W0.21W0.23W
Sleep0.34W0.32W0.45W0.46W
Idle2.83W3.25W4.5W4.76W

In this comparison, the Surface Laptop has a smaller carbon footprint but the MacBook Pro is more energy efficient.

Conclusions

Apple produces the most environmentally friendly laptops from both a carbon footprint and energy efficiency perspective, but it depends on which model you compare.

We are also at a point where energy efficiency improvements have minimal impact on the individual user, from a cost perspective. However, given the mass market for these devices improvements are significant in terms of general energy usage trends.

Comparing the devices is interesting but if there is one thing to take away from this analysis it is: don’t buy a new laptop. The majority of the environmental footprint is in the production. If your laptop is working fine then why buy a new one?