You're mixing up several technologies and techniques there, thin client doesn't necessarily equal VDI, and the cloud does not necessarily mean thin client.

Thin clients operate well in schools due to the fact that they can do 95% of the work 95% of the time. The server back end uses drastically less power than a suite of full PC's.

Rolling out VDI would change this significantly - the extra overhead of VDI would mean our current 3 server farm would have to roughly double in size to handle the same number of clients. This would defeat the energy savings completely. But not the management savings (ie. having to have more IT staff to support them, more office space to support those staff etc...). But I've not seen VDI marketted as an energy efficient solution. It is marketted as an administration solution. Similar to blade workstations - all the admin is done in one place.

What has 'the cloud' got to do with VDI and thin clients by the way? Yes it can be linked but not in the way your post seems to imply.

I see you're a fan of Chuck! Love that programme. Really appreciate the comments. You're right there is a mix of technology because the Wyse white paper included them because they are based on server technology I guess.

Any server back end can be virtualised to reduce the number of physical servers but we believe the energy consumption of servers that take the place of PCs are regularly miscalculated and that creating copies of desktops to host on servers is a great business model and as you say works for the majority of tasks required in education.

The VDi is an internal form of the Cloud Computing model, and is marketed with thin clients. For me the Cloud model is a high availability solution that requires internet access so that you can get at your software and applications etc and is pretty well priced.... but there's an energy output that is unseen by the end user that will eventually be factored into the cost.

Green IT should take into account a reduction in hardware, yet most CIOs, Network Managers would name the thin client model as Green IT because believe me that is how it's being marketed in the past and even now. Thin clients mean more hardware and fatter servers, and a performance trade off.

You no longer need a suite of full PCs or thin clients, you can reduce the number to 1/8th of the original amount using a fat client running multiseat computer software and provide users with 100% ability to work 100% of the time, with the least possible environmental damage.

So for us, thin client, cloud computing (most cloud computing hosts would upsell you some sort of defeatured notebook), VDi are all interlinked and DO save money, simplify management and offer great uptime and processing power.

However, and I think I've been unfair on you EduGeeks, the business community believe that VDi, thin client, Cloud computing are the greenest desktop IT solutions. They do / can overlap, but the carbon footprint of the server side aggregated with the hardware requirements tends to be missed out. It is clear to me that the EduGeeks are better informed than many of their business counterparts.

Being part way through a VDI roll out I do find your post interesting, and agree that sometimes the Server room power consumption calculations are a bit shoddy. however you have missed that the expected lifecycle of a thin client terminal far exceeds that of a desktop PC, meaning less frequent cases of sending stuff to be WEEEcycled, also as a thin client has less parts even when it is WEEEcycled there is going to be less material going to landfill etc.

there is also less materials and processes used in the production, again lowering the carbon footprint. although it may be nigh on impossible to calculate this benefit it is still there.

I also find your mixture of terms like thin client, VDI and The cloud to add confusion to the debate

Hey Skree,

Fantastic contribution, cheers. I think the confusion over the terms is a good point one raised earlier too. I love the term WEEEcycled too! I know of schemes in Derby by top ICT accredited schools like West Park School where PCs are recycled, resold or provided to disadvantaged students. I posted the same blog on a business forum called 2degrees and had a rep from Sun reply with the lifecycle of a thin client device too and I replied that if necessary the PC can be turned into a thin client. There are positive arguments for the thin client model don't get me wrong (if the economies of scale exist), however I am a big believer in giving the end user processing power at the desktop AND giving the IT Managers the means to easily manage such a network, and the top trump card at the moment is multiseat computing.

A thin client uses 0.5 tonnes of non renewable raw materials in manufacture and then there're associated packaging and shipping costs. A PC can use up to 1.7 tonnes. If a PC can be split into 8 users, then the carbon footprint before it reaches the desk not including ship and pack is 1.7 mt of CO2. 8 thin clients would be 4 mt. Then add in the server side power consumption and CO2 contribution and ship and pack and you have a real environmental IT argument for Multiseating. Just to clarify:

Cloud = hosted applications accessed by any device most typically a defeatured version of a PC that handles the processing.

VDi = enterprise thin client model using the cloud as a host and servers as processing power.

Thin client = defeatured end user environment taking advantage of virtualised servers that handle the processing.

I know they're not the same but they're pretty similar and will converge. We're in pilot with some corporates and hope to get some comparison figures. I'd love to have my resellers get involved with the larger user orders over 500 seats say but at the moment I will stress that because of the network management side of things I wouldn't like to bet my house on Multiseat computing working on a massive user scale. As I say I am a believer in giving end users processing power without the complication.

VDi = enterprise thin client model using the cloud as a host and servers as processing power.

Or using local servers to provide the hosting power. XenDesktop, Vmware View and Sun Ray 4 are examples of this done locally.

Further the energy savings using thin client computing, have a blast at the following website;

Raydesk: Desktops > Sun Ray desktop clients > Sun Ray energy savings calculator

Having all desktops in our Business changed for Thin Clients, we're looking at almost £7000 a year in energy savings, added more savings on life expectancy and the likes.

The only downside is the new 700w server you've just bought and the SAN to power these, however consolidating other servers onto the new server saves even more power.