Environmental issues are a common part of most IT strategies, as awareness of carbon footprints and the levels of energy use associated with technology have become widespread. But how can cloud computing help to improve sustainability, and what role should the cloud play in green IT planning? This HP whitepaper examines the green credentials of cloud computing.
What is green IT?
Green IT aims to use computers and IT resources in a more efficient and environmentally responsible way. Businesses are becoming increasingly dependent on technology, with staff working on desktops, laptops, netbooks and smartphones all day, which are connected to servers running 24/7.
Adopting virtualisation and cloud computing systems can save companies a great deal in energy costs, as the number of internal servers used can be reduced and application management can be outsourced to a cloud provider. The cloud provider's energy usage can be consolidated and made more efficient by supporting multiple numbers of cloud customers with server capacity and application services - such as software-as-a-service (SaaS) - as a result.
Because the SaaS pay-as-you-go model allows firms to choose only the specific applications they need at any given time, instead of having to pay for an entire suite of software on their premises, they can save money. IT staff costs can also be reduced because upgrade and maintenance responsibilities will be shouldered by the cloud provider.
If firms use dedicated hosting services via the cloud, they can also shop for "green" hosting providers that use solar, hydro or wind power, as part of their energy supply from the grid. A number of hosting companies in the UK and other parts of Europe have already sourced some kind of green power supply.
Infrastructure-as-a-service (IaaS) via the cloud offers scalable computing power to companies without requiring them to bring hardware services in-house. With IaaS, cloud providers supply the infrastructure as needed to support businesses running their own applications. By converting infrastructure to a periodic and predictable cost, a company can avoid unexpected repairs and upgrades while being assured of maximum uptime.
IaaS provides the scaling of processing power, so that users are never caught in the position of overload, while avoiding the costs of under-utilised capacity. Like SaaS, the cost of IT staffing is reduced through reduced internal maintenance and upgrade and support costs.
Another way to save power is to consider thin-client or "server-based computing" to cater to all or parts of your business. A thin-client computer using a simple web browser and/or remote desktop virtualisation software can use up to about half the energy of a standard desktop loaded with its own dedicated applications. The applications can instead be accessed on demand from a remote server from any location via the cloud.
In addition, firms can save further cash and become greener at the same time by moving their documents and other data into the cloud. Instead of staff being forced to use inefficient and time-consuming filing cabinets filled with hard copies, and copying and printing out endless pieces of paper for themselves and others, firms can make those documents available electronically by storing them securely in the cloud. Staff can then access them from any location at any time.
This saves on paper and ink and reduces printer carbon emissions. It can also reduce confusion, as often there is only ever one version of a document to cope with. Anyone who needs to can access previous versions or edits, and in most cases there is very little need to print anything. If you need to send a copy to someone you can simply email it to them.
Does the cloud have an environmental impact?
Environmental campaigning organisation Greenpeace has previously published reports which have questioned the amount of energy being used up by data centres hosting cloud services. The report criticised some large companies who use the cloud to deliver on-demand services to both consumers and businesses. These included Google, Yahoo, Facebook, Apple and Microsoft.
Greenpeace said these companies' data centres, providing cloud-based services, were not tapping into enough green power sources on the power grid, such as wind and hydro power. While Google and Yahoo have built individual data centres with an improved greener energy mix, Greenpeace said most of the power at those sites relied on "dirty" sources of energy, like coal and nuclear. The reliance on dirty power applied to other data centres used by those two firms and the data centres operated by the other companies covered in Greenpeace reports.
While some see nuclear power as a green energy when compared to energy created from coal, those in the green movement don't. And putting aside the Greenpeace reports, there are still many who believe that adopting cloud services may well save firms money through the consolidated supply of services, but that the positive environmental impact is uncertain, as more energy is simply being used in extremely large and remotely connected data centres.
Power consumption and energy-efficiency
Basically, the impact of cloud computing on power consumption will depend on its energy-efficiency, its impact on overall demand for computing, and the extent to which cloud computing providers power their operations with electricity from sustainable sources.
Analyst Ovum says that cloud computing typically boosts energy efficiency per unit of output. But, on the other hand, the cloud could be expanding the scope of computing, thereby driving higher aggregate electricity consumption.
This effect – technological progress enabling greater efficiency, increasing usage, and driving power consumption upwards rather than downwards – is known as "Jevons paradox." The concept was invoked to explain the apparent increase in coal consumption, following the improvements in steam engine efficiency in the 19th century.
Greenpeace has challenged cloud providers to use their market clout to drive green changes in the electricity supply chain to reduce carbon emissions. Ovum agrees, saying, "In this regard, we agree with Greenpeace: greater reliance on renewable or zero-carbon energy sources in the cloud computing generation is imperative."