It all depends on the equipment being repaired.

Let’s look at data for an office PC. According to an IVF 2007 report, about 80% of the energy and carbon impact is from the use phase, and only 20% is from the manufacturing and disposal. (The report in question is succinctly entitled ‘European Commission DG TREN Preparatory studies for Eco-design Requirements of EUPs. Lot 3: Personal Computers (desktops and laptops) and Computer Monitors. Final Report (Task 1-8)’.)

Or, look at Carnegie Mellon’s EIO-LCA database, which covers all sectors of the economy, and look at the sector ‘Electronic computer manufacturing.’ It takes about 11 GJ of primary enegy and 1 metric ton of CO2 to make and dispose of a $2,500 server, but by my calculation that server will use about 120 GJ of primary energy to make the necessary electricity, which will emit 7 metric tons of carbon at US CO2/MWh rates. So, the use phase is over 90% of the energy and over 85% of the carbon.

These numbers aren’t for servers specifically, but they’re probably reasonable, and they show the use phase is much more important.

BUT, you should only get rid of your old servers if the new server’s actual efficiency improvement is enough to make up for having to build a new one.

Here’s a scenario:

(a) A server you already have took 20 units of energy to make (which you’ve already ‘paid’), and it will take 80 units of energy to run for another 5 years.

(b) A new, more efficient server server that does the same amount of IT work would require 20 new units of energy to make, and it would take 59 units of energy to run over the next 5 years.

So, buying a new server which is 1-59/80 = 26% more efficient would require a total of 79 units of energy, while continuing to run your old server would be just slightly worse, at 80 units of energy. But if the new server was only 25% more efficient, you’d need 64+20 = 84 units of energy to manufacture and run it, which is worse than just keeping the old server.

So, my recommendation is that the UK government and others not create a blanket policy of keeping all old servers as long as possible. Instead they should do a quick ‘back of the envelope’ calculation to determine if the efficiency benefits of a new model are big enough to beat the energy/carbon penalty of building something new. What they’ll probably find is that it’s well worth replacing very old, very inefficient equipment, but that it’s not worth replacing relatively recent equipment whose efficiency is just a step or two behind today’s models.

So as you can see from the above, it is far too simplistic to say that repairing and re-using old technology is ‘Greener’ than manufacturing new.

I have passed on a 5 year old laptop to a family member who has been using it every day for over a year. Most people I know with PC laptops get rid of them after 2 to 3 years.

I’ve seen offices full of Mac’s that are over 5 years old, you can tell by the case design, running on G4 chips that predate the Intel switchover, that are still very productive. Whilst I have clients who buy the latest and greatest Sony Vaio laptops every year and still complain that they slow down (because they are laden with crapware).

You need to extend the definition of repair to include these types of system recovery or repair. The chances are that many in the IT industry will label unrelated work as a ‘repairs’ to avoid charging VAT.