The green agenda is starting to have a real effect on organisations’ IT spending decisions.

Ninety-five per cent of companies want more environmentally-friendly computer systems, according to a survey conducted by the Green Technology Initiative last week.

And 53 per cent of respondents to a global Ipsos Mori poll said they were more likely to purchase services from a company with a good environmental reputation.

In the past week alone, the Insolvency Service ­ the government agency which handles bankrupt companies ­ has signed a £20m five-year contract with IBM for thin-client hardware to help cut energy costs.

And Barclays announced similar plans for 10,000 desktop systems.

In the growing market for environmental IT, the big players are jostling to be regarded as the greenest vendor.

IBM, HP and Dell have all launched environmental initiatives in the last six months, and the providers’ own experiences are central to their sales pitches.

The issue for customers is to know how to rate the suppliers’ performance benchmarks against each other for a clear view of how the different environmental services compare.

HP’s goal is to cut the combined energy consumption of its operations and products to 20 per cent below 2005 levels by 2010.

The firm reached its initial goal to recycle half a billion kilograms of electronic equipment in July, and will process the same amount again by 2010.

IBM’s recycling efforts are quantified in a different way.

In 2006 the company took back £100m worth of equipment, and it plans to recycle even more this year.

Overall, IBM’s Big Green project will spend $1bn (£504m) a year on developing energy-efficient technologies. The company is also setting up a team of 1,000 specialists to help build a client roadmap based on its own experiences.

Dell simply says that it wants to be the first in the sector to become carbon-neutral. However, it has set no date or specific emissions target.

Green pressures are leading to a change in supplier culture, said Ian Brown, senior analyst at Ovum.

“There will be a shift in spending from products to services because companies will want computing resources on a utility basis,” he said.

Thin-client architectures are a popular route to greener IT because the model relies on a central server rather than multiple desktop processors. The downside is the complex infrastructure remodeling that such installations require.

In the short term at least, suppliers with relevant expertise have much to gain, according to National Outsourcing Association director Mark Kobayashi-Hillary.

“The suppliers are the experts in green IT at the moment so it makes perfect sense to outsource environmental projects to them,” he said.