How to get Windows to report your power management
Windows’ power management reporting isn’t perfect, but it does exist and it might save you money. First introduced in Windows 7, the command line utility has an parameter. This watches your machine for a minute before spitting out an HTMLformatted report into C:/windows/system32.
You might be amazed by the level of data (on my ThinkStation C20, it thought I might have missed a BIOS update to take advantage of the higher levels of sleep modes and CPU Core Parking, for example), but I was more disappointed by what it didn’t say. There’s no blanket statement of N watts of power being consumed over X count of seconds.
A small glint of hope is visible from deeper Googling, in the form of Microsoft Research’s Joulemeter, only to be withdrawn again by the encroachment of Visual Studio into the subject – a sledgehammer to crack a tiny little nut if ever there was one. By all means tread the path I did, because several online libraries have retained the download – but be aware that lowreputation sites love to catch out the unwary with this type of file.
It seems almost instinctive that you should know how much power you’re consuming, and that a PC should have the required sensors and technologies to figure it out. The truth is that it used to be a decent assumption, dealing with data centre servers. It’s not going to be as safe when dealing with laptops or hybrid tablets because the amounts of current involved are tiny. This is why Microsoft treats the whole question as a research project, trying to go backwards from the compute being performed and derive the watts consumed from there.
Unless you fancy buying a plug-in USB power meter, or a professional tool from the likes of Fluke or Megger, this might turn out to be a use for a domestic smart meter – but only if you can turn everything else off, or do some fancy addition and subtraction logic according to the time of day (so, work out what services only run at certain times). There has to be an easier way! room, and knew that the likely fate of our servers was trial by water, not by fire. As with a lot of these sensors, the flood detector didn’t do very much: it gave us maybe just long enough to get to the office to see the top of the server racks sink beneath the waves.
There are serious points to be made about the state of sensor availability and deployment in our brave new world. Most of the sensor industry still wants to make a dedicated, single-purpose little plastic box with a black-and-white LCD on the front: take a leisurely peek around the Airthings site and you’ll find them still selling such things. While these devices form a terrible attraction to the technical collector on eBay, the simple truth is that the minute you see a sensor reporting to you via an app on a smartphone screen, or into a bit of logic on an IoT automator service such as IFTTT.com, the penny immediately drops: it’s not about one brand or specialist providing all the possible readings in some super-smart device like a Star Trek tricorder. It’s much more about taking the signals from simple devices and amalgamating them up in the cloud, with the eventual aim of smartphone display jointly or severally. For example, I’m sure a lot of Nest customers would want to tap on a graph that shows temperature so they can check that their controller has done what they asked it to do.
Okay, so that last bit was somewhat facetious – except, I think a lot of home sensor use cases are facetious. Really. Hooking up a