How Green is your Apple?

In an age where green is increasingly becoming the 'in thing', how does our favourite fruit inspired computer maker score? In a
survey of enterprise technology users, Apple were already seen as one of the companies on the eco frontier. Environmental groups such as Greenpeace, however, have slammed companies including Apple on their green credentials. In the
most recent rating of companies, Apple scored a measly 4 out of 10, although it is worth noting that the highest score, from Sony, was just over 5. Apple has frequently been the target of abuse from Greenpeace, with the group even dedicating a
mock website to them.
In the article that follows, all the key players in Apple's current line up (excluding cinema displays) have been analysed and graded on a scale from A (almost perfect) to E (fail). Criteria considered in these ratings included; energy efficiency, recyclability of the product, what it is made of (eg: plastic = bad), whether it contains any hazardous substances and the longevity of the product.
Disclaimer: All ratings and comments should of course be taken with a grain of salt. Figures derived from the various calculations were used in order to give a rough idea only and may be either significantly conservative or overstated (noted next to them). Although I have a background in environmental science and sustainable development, the following article remains solely my opinion and interpretation.
In order to calculate the energy impact of Apple's desktop range, a number of approximate figures were calculated using the following assumptions;
Idle power consumption figures derived from Apple's
environmental specifications. Idle power consumption defines the state where OS X has fully loaded and the computer is not actively running any tasks. Idle power consumption does not include the power consumption of any monitor being used with the Mac Mini or Mac Pro as these will vary greatly. Idle power consumption for the iMac range does include the monitor being on and at full brightness. All calculations were based on idle power consumption ratings, as the computer is likely to spend the greatest amount of time sitting in an idle state or close to it. As a result, all figures should be seen as quite conservative. All values are approximate and in some cases have been rounded to the nearest whole number.
Yearly power consumption, yearly cost and yearly CO2 emissions calculated on the assumption of daily use of 10 hours per day, 5 days per week, every week of the year.
Yearly 24/7 power consumption, yearly 24/7 running costs and yearly 24/7 CO2 emissions assumes the computer is running for the entire 8760 hours of the year.
Electricity cost used was an average value of $0.15 per kWh. This can vary greatly. See the end of the article for how to calculate your own.
CO2 emissions calculated as follows; Total Idle kWh used per year x 0.80 (as 80% of power generation in Australia is from fossil fuels). That figure was then multiplied by 1.21kg - the average amount of CO2 from the production of 1kWh of fossil fuel energy.
In terms of energy efficieny, the
Mac Mini can't be beaten. As Apple advertises, most of the time it consumes less than half the power of a standard light bulb. Combined with a high efficiency monitor, the impact of the mini can be almost neglible compared to other Macs and PCs. The Mini does lose points however due to the fact it still contains plastic and several toxic components. Hopefully these can be eliminated by Apple if they choose to update the Mini, which at this stage is anyones guess.
Overall Grade: A-
In August last year, the
iMac range made the transition from being primarily based on petrochemical derived, toxic and difficult to recycle plastic to a much friendlier mix of primarily glass and aluminium, a point Steve gloated about during their unveiling keynote. It was
recently reported that the iMac as a whole unit used up to two thirds less power than a comparable headless PC - a very impressive achievement.
The
iMac 20" model scores relatively well as it is quite an efficient machine that is very recyclable. Both models, however, loose points due to the fact that they most parts are not user replaceable or accessible, thus bringing the score for product longevity down.
Overall Grade: B
The
iMac 24" model loses points due to it's energy consumption. Although you do get 4 extra inches, the amount of extra energy it requires is not neglible and can be seen approaching that of the headless Mac Pro.
Overall Grade: C+
So we come to the beast. The mother of all Macs in more ways than one. The
Mac Pro by all accounts is a power guzzler. Although it's idle power consumption is not unreasonable for a machine in it's class, how often would a computer targeted at high end industry uses such as video rendering be sitting idle? It's when the Mac Pro gets going that things start to get a little crazy with the machine having the potential to draw 980W. In the hypothetical but unlikely situation that a Mac Pro was running at full power draw for 24 hours a day 7 days a week for the whole year (such as a dedicated video rendering machine) we would be looking at a running cost of ~$1300 and over 8 tonnes of CO2!! As it is, running the machine in an idle state in this style will result in a power bill of over $200 and about 1.5 tonnes of CO2. It's not all bad for the Mac Pro though, it's all aluminium design scores big on the recyclable scale and having full access to the internals in addition to it's build quality make the Pro the best scorer in the product longevity category. These things helped pull the Mac Pro up from a complete environmental failure. I have to note here that I am not targeting the Mac Pro, but rather what it is. Although not considered explicitly in this article, energy consumption for comparable PCs is certainly very similar if not higher than the Mac Pro. In addition to high energy consumption, the high price tag and number of features make this machine overkill for most users.
Overall Grade: D+
In order to calculate the energy impact of Apple's portable range, a number of approximate figures were calculated using the same aforementioned assumptions in addition to the following;
Idle power consumption for all models assumes the computer is plugged in and the display is at full brightness.
24/7 usage was not considered for laptops, as they are less likely to be used in that capacity than a desktop machine, in this users opinion anyway.
Charging power consumption is the state where the battery is charging via the supplied MagSafe power adaptor. Energy consumption during this period can vary signicantly but is generally close to the specified wattage of the power adaptor, thus this value was used. As a result, these figures should be seen to lean towards overestimation. Thanks to Jedda for the help with this issue.
A charge as defined below as 'per charge' was averaged to take 2.5 hours. This varies significantly depending on the model of your computer, it's state while being charged and the condition of your battery. To calculate this for yourself, multiply the charging power supply wattage by the time taken to charge rounded to a whole number, eg. two and a half hours would be 2.5 or 1 hour and 45 minutes would be 1.75. Divide this number by 1000 to give you the kWH used per charge. The cost and the CO2 emissions of this can then be calculated as outlined at the end of this article.
The
MacBook is another one of those 'which way to look at it?' products. On one side of the coin it has fantastic energy efficiency numbers, almost up there with the MacBook Air. On the other, however, there is no overlooking the fact that this thing is made of a heap of plastic, and plastic = bad. The baby Mac laptop does score well on the longevity index though, with a user replaceable battery as well as the ability for users to upgrade RAM. Bring on those rumoured new
aluminium cases and the MacBook would be up there with the Air, but not quite yet.
Overall Grade: B
We now come to Apple's eco pride and joy, the
MacBook Air. The Air is as clean (lame pun intended) as they come with regards to use of toxic substances and also boasts that it's packing is made from 100% recycled material. Perhaps as an added benefit of being designed to be so small, the Air is a very very efficient machine, with the lowest power consumption of any Apple model; an almost negligible 10W when idle. The Air also does wonders for the air (again, lame pun intended) with a very small carbon footprint. Around about 25kg a year with daily use. The only category where the MacBook Air might fall down is in product longevity. The Air does not have a user replaceable battery, although it's price probably means most people will get a battery replacement as opposed to buying a new one as they may with the iPod for example.
Overall Grade: A
The
MacBook Pro scores very well on energy efficiency. The 17" model uses only slightly more power per year than the Mac Mini, except in this case it is a much more powerful computer running a rather large screen. It also scores very well on the recyclable front, with a primarily aluminium construction. Similar to the MacBook, the MacBook Pro also has a user replaceable battery that is readily available for purchase as well as the ability for users to upgrade the computers specs, both adding points to the longevity column.
Overall Grade: A-
The recent transition of the
iPod range to full aluminium was a positive step by Apple. Things have also improved in recent years with regards to Apple's use of toxic substances in the iPod. The entire range now complies globally with the restrictions of hazardous substances list. The iPod power adaptor also complies with and exceeds energy efficiency requirements. The big loser for the iPod though is the fact that it's battery is not easily user replaceable. It is common knowledge that batteries are consumable products that are built with the idea that they will cease to function properly after a certain period of time. By sealing this inside the iPod, it means that once the battery has run it's course, although the rest of the iPod may work fine, most users end up simply buying a new one due to the costs and difficulty of battery replacement. Good for business? Sure is. Good for the longevity of products and the environment? Not so much...
Overall Grade: B
Apple's pride and joy, the
iPhone, is a hard one to decide on... The device has several pluses including a power adaptor that exceeds energy efficiency requirements and the excessive consumption beating power of acting as three devices in one. On the flip, however, the transition from the first generation iPhone's more recyclable metal construction to the petrochemical derived plastic back of iPhone 3G is a big no no in the saving the world handbook. The iPhone also hasn't been too popular with my personal favourite chain-themselves-to-trees activists, Greenpeace. They
slammed Apple over the hazardous substances found in the first generation iPhone, which sparked
threats of a lawsuit. Greenpeace
claim that things haven't changed with the iPhone 3G, although we won't really know until someone does some tests. For the record, Apple claim on the
environment section of their website that they plan to voluntarily phase out the hazardous subtances that Greenpeace targetted by the end of 2008. Rating the iPhone is a very difficult task but for the sake of the article I will give it a very tentative mark...
Overall Grade: B-
Conclusion
As I said at the start of this article, the conclusions drawn from this article should of course be taken with a grain of salt. While the numbers give a good idea of things, the rest of it is a lot of opinion.
If you are now feeling a little guilty about your computers impact on the environment, perhaps you could consider buying Green Power for your home. Usually for a few extra cents per kWh you can know that part or all (your choice usually, with prices varying) of the power heading to your home is coming from green sources. Be careful that you are actually getting what you are paying for though.
For anyone who runs their home from solar power or is considering doing so, a laptop certainly is the way to go in terms of energy efficiency. With a good laptop stand and external mouse and keyboard, a laptop can be almost as good as the desktop, just with the added benefit you can pick it up and take it with you!
Finally, there is an important lesson that can be learnt from this experiment - simply not to leave things on! With the sleep mode built into OS X being so good, there really is no excuse to have your computer burning away when not in use. Be sure to check your energy settings (accessible from system preferences) and make sure your Mac is set to go to sleep (not just turn off the display) after a period of inactivity of your choosing.