How does Powerdown work?

Powerdown is a energy management tool that allows computers to be turned on and off according to a schedule supplied by the system administrator. Each Powerdown client regularly retrieves and stores the latest schedule from the network, allowing Powerdown to carry on providing energy savings even when the computer is disconnected from the network (e.g. laptops). Different groups of computers can be configured to use different schedules.

Windows already has power saving features. Why do I need Powerdown?

Windows does indeed have a range of built-in power saving features but users rarely enable them and the Windows management tools currently provide no way for system administrators to enforce power saving settings on every machine. Powerdown optimises the operating system's own power settings and allows you to ensure that they are enforced consistently on all of your computers.

The Windows power saving features all work on the basis of detecting user inactivity and turning off the computer, or some of its constituent components, after the user has been inactive for a certain period of time. The out-of-the-box settings are not particularly aggressive and Windows can wait a significant amount of time to turn off a computer (30 minutes or more) after it has last been used. Although the power settings can be tuned to reduce this delay the user still does need to leave the computer running but inactive for some period of time before Windows responds to this.

In terms of energy use, energy cost and carbon emissions, the delay that the Windows power saving features require may not seem significant when you consider a single machine and a single day's use. But when you consider a large network with hundreds or thousands of computers which are running every day, these individual delays suddenly start to add up and make a significant contribution to carbon emissions and energy costs. Powerdown overcomes this by ensuring that computers enter a low power state when they have been idle for a maximum of 10 minutes.

Powerdown was created to produce more aggressive power and emissions savings and was born out of the realisation that, in many organisations, the majority of computer users have regularly daily work schedules. If we know that users finish their day's work at a particular time (e.g. the marketing team all finish at 17:30) or that certain groups of computers are not used after a certain time (e.g. the college computer labs close at 19:00), why not just schedule computers to turn off at these times? This is exactly what Powerdown does.

Do I need a server to use Powerdown?

No, it is not strictly necessary to have a server to use Powerdown but it does help make deployment and operation easier if you have a server available. Competing solutions often trigger changes to the power state of each computer from a scheduler running on one or more servers.

Powerdown is a client-only solution and does not make use of a server in this manner. Instead Powerdown is driven by policy files which the system administrator defines and these policies are made available to all Powerdown clients by publishing them in known locations, on your network such as on network shares, network drives or web servers. Obviously a server is required to support these publishing options but it is also possible for Powerdown to be configured to retrieve policies from a known location on the client and not from the network (see Does it work on standalone computers?
). If you choose to operate Powerdown in this manner then you will not need a server.

Is it necessary to have a Windows domain to make use of Powerdown?

No, Powerdown is designed to operate in the widest range of computing environments including single standalone computers, small Windows workgroup networks and fully managed Windows domains. Powerdown becomes slightly easier to deploy and manage if you do have a Windows domain but it is not a fundamental requirement.

Does it work on standalone computers?

Absolutely! One of the unique features of Powerdown is that it does not require computers to be connected to the network for energy savings to be realised and for automatic shutdowns and restarts to be performed. Powerdown achieves this operation by caching a local copy of the policy defined by the system administrator and using this to drive its operations if it becomes disconnected from the network. Because Powerdown always installs a default policy on every computer this feature also allows Powerdown to be used on standalone machines that have never been connected to the network. All that is required is for the system administrator to modify the local copy of the policy to optimise the energy usage of the machine.

Can Powerdown be managed through Group Policy?

Yes. Powerdown is designed to operate in large, fully managed Windows domain environments and is supplied with administrative templates which can be installed on your domain controller to allow client configuration to be controlled through Group Policy. By deploying and configuring Powerdown through Group Policy it is possible to achieve and automated deployment of Powerdown.

Not every aspect of Powerdown can be configured through Group Policy. For instance, configuring scheduled shutdowns and restarts is not currently supported through Group Policy. If this feature of Powerdown is required in your environment then you will still need to create policies and publish them in known locations on your network using the Powerdown Policy Editor tool.

Why does Powerdown allow users to postpone a shutdown?

Although many users have regular work habits and computer usage patterns, there are still times when there is a need to deviate from the normal behaviours. For example, if an employee has been given a particularly important and urgent task they may work later than normal one day to complete that task. It would be inconvenient and frustrating for a user in that scenario to have the computer forcibly turned off at a specific time when they were still trying to use it. For this reason Powerdown allows a user to postpone the shutdown operation for a short period of time. The user can continually postpone the shutdown; each time they postpone the delay between subsequent shutdown prompts increases so that the user does not experience excessive interruptions of their work. However Powerdown will continue to prompt the user at regular intervals until they either shutdown the computer or leave the computer unattended, at which point Powerdown will shut it down automatically.

Powerdown is installed on my computer - can I still turn my computer off manually?

Yes. Powerdown does not replace the standard shutdown mechanism provided by the operating system, it simply automates the process. You can always turn off or suspend your machine manually in the normal way without any adverse effect on the operation of Powerdown. If you manually place a computer in low-power state Powerdown will still restart it automatically when required. Turning your computer off when you have finished using it is the best way of of reducing your energy consumption.

What happens if a user manually reconfigures the operating system power schemes?

Powerdown configures power settings on each computer by creating a custom power scheme. Under Windows users have rights to change the power settings of their computer. Powerdown forcibly applies the settings specified by the system administrator every time a user logs in and every time that the policy is refreshed. Even if a user changes the computer power settings Powerdown will change them back to the system-wide setting shortly afterwards, although the reduction in energy consumption may be sub-optimal for a short time.

Does Powerdown work with standalone computers and laptops?

Yes. Powerdown has been specifically designed to work with mobile computing devices such as laptops and Tablet PC's. Because the Powerdown application runs on the client computer it can still be used to shutdown computers when they are not connected to the network.

Powerdown has also been optimised to take account of the unique features of portable computers. For instance, there have been a number of widely publicised cases of laptops overheating or causing fires due to problems with batteries or turning themselves on whilst being carried in a bag. As a safety feature Powerdown will prevent automatic restarting of any portable computer which is running on battery power.

Why is Powerdown particularly suitable for large networks?

Powerdown is more than just a mechanism for turning on and off groups of computers and it has been designed specifically for easy deployment and management in large business networks. The features of Powerdown which make it particularly suitable for such environments are

• Designed primarily for automated no-touch deployment via Active Directory
• Support for different policies for different groups of computers, allowing energy savings to be optimised for specific needs
• Easy schedule publishing and automated schedule updating simplifies management and configuration of large numbers of client computers
• Awareness of electrical and network loading issues involved in automatically starting many computers simultaneously. Even if the schedule tries to restart all the computers on the network at exactly the same time, Powerdown adjusts the time at which each individual computer will restart to ensure that electrical networks are not overloaded by current surges and that networks and servers are not innundated with network traffic.
• Simple configuration of managed clients via Group Policy

How does Powerdown differ from other remote reboot/shutdown schedulers?

There are a number of remote shutdown/remote restart utilities available which allow a network administrator to trigger a remote computer to shutdown or reboot via the network. Some of these utilities allow the scheduling of shutdowns/restarts for individual computers but this is generally controlled by a central server and client computers must be connected to the network for shutdowns/restarts to occur.

Powerdown also allows shutdowns and restarts to be scheduled but it adopts a more powerful and more flexible approach

• Powerdown operates entirely on the client computers meaning that no central server process is required and that computers can be shutdown and restarted even when they are disconnected from the network. This is a particularly important consideration for mobile computers, such as laptops and Tablet PC's, and standalone computers.
• Remote shutdown/restart utilities often do not give any users logged in to the client computer the option of preventing the shutdown/restart from taking place. Powerdown acknowledges the fact that sometimes it might be inconvenient to the user to have the computer shutdown and it always gives the user the option to indefinitely postpone a scheduled shutdown.
• Many remote restart utilities only allow an immediate restart to be performed. Powerdown can schedule a restart for any future time.
• Other restart utilities often rely on the Wake-On-LAN capabilities of PC hardware. Our tests have shown that this can be unreliable in large Windows networks and can result in numerous 'false positives' where computers are reactivated unnecessarily, thus reducing the energy saving potential. Powerdown does not use Wake-On-LAN for restarting, so PC's are only reactivated when they actually need to be.
• Powerdown works with the operating systems own power saving features and optimises these to achieve maximum energy savings

Powerdown does more than simply schedule shutdowns and restarts; it also optimises system power savings to quickly turn off idle computers so that maximum energy savings are achieved.

How much does it cost?

Powerdown is offered in several distinct licence bundles.

• £FREE!    Home Network Licence for up to 10 computers
• £FREE!    Educational Licence for unlimited computers in the institution and for personal use by staff and students
• £249       Small Business Licence for up to 50 computers
• £449       Medium Business Licence for up to 250 computers
• £749       Enterprise Licence for up to 1000 computers
• £999       Site Licence Licence for unlimited computers

How much money will it save?

Our analysis shows that cost savings of up to 40% can be achieved in an environment where computers are traditionally left running 24 hours a day, 7 days a week. At current prices this results in a saving of around £30 for each computer every year. The actual cost savings that you will achieve depend on a number of factors including the hardware configuration of the computers you have, how long they are used for and how long they were left running for before Powerdown was installed.

What energy savings can I expect to make?

The actual savings you will make depend on a number of factors, including how many hours a day your computers are used and how many hours a day they were used before you deployed Powerdown. An organisation that had many computers running all the time can typically expect to achieve savings of up to 40% in the energy required to run their computers. Our calculations show that a typical business could save up to 6% on its total annual energy bill by deploying Powerdown on its computer systems.

What is the payback period?

The payback period depends on the actual cost savings
and energy savings that you make in your your particular environment and this is affected by a number of factors, as described above. The most important influence on payback time is the amount of energy you were using before you deployed Powerdown. Our calculations suggest that a typical business will make sufficient energy savings to recover the cost of their investment in Powerdown within 5 to 10 weeks.

What are the future plans for the Powerdown product?

Future versions and new editions of the product are planned, each of which will introduce new features and capabilities into the Powerdown product family.