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Five PC Power Myths Debunked
snydeq writes "Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year, according to Energy Star, savings that can add up quickly for large organizations. Yet most organizations remain behind the times on PC power management, in large part due to common misperceptions about PC power, writes InfoWorld's Ted Samson, who outlines five PC power myths debunked in a recent report from Forrester, ranging from the energy savings of screen savers, to the energy draw of powering up, to the difficulties of issuing patches to systems in lower-power states."
NSLU2 + bus-powered USB drive + debian + torrentflux-b4rt
Max 10W drain, with one drive it's nearer 5W. Add in ushare and you have a low energy box that has a web interface for torrenting stuff and can stream the results to your xbox. All for $60 (or so) and the price of the drive.
The EPA awarded my company with one of their top awards this year for improvements to our facility, and energy efficiency. Overall we cut energy consumption 50%, but also used our energy more smartly, including a dedicated ducting system from our server room to the building entrances. We calculate that our servers put out between 8,000 & 12,000 Btu an hour. Most of our overnight heat now comes from the servers (which have to be on 24/7 for off site access), and we've reduced our server air conditioning loads by 80% annually. We're now beginning to implement this change into bank designs.
In almost every application, it's ideal to shut off computers when not in use, but there are some business based situations where it makes sense to better harness waste heat from electronics, instead of fighting it with energy intensive air conditioners.
http://www.energystar.gov/index.cfm?c=sb_success.sb_successstories2008_johnsonbraund
Unit errors are generally a sign in technical fields that a report hasn't been well thought out. No engineer proofreading this would have missed such a blatant error which means that an engineer didn't proofread it.
If an engineer did not proofread it, an engineer did not likely do it. Therefore, the content of the article was likely done by an incompetent hack and charging $279 for the report is a way of hiding the fact that it was written by a hack.
If you need a convenient size, that's what the prefixes are for. A MJ is as conveniently sized as a kWhr. Whr is more convenient in some applications for calculating energy used over time, so it's a reasonable thing to use there.
Miles per gallon is a silly set of units to use. Metric units would be nice, but have little practical benefit for most usage cases (unless we were to switch to selling liters of gas and marking roads in km, but that's unlikely). The problem is that miles per gallon is backward. It should be gallons per mile (or 100 miles something similar for convenient scale). Why? Distance is the independent variable, not the dependent one. You might want to know how many gallons you'll use on a 200 mile trip, but it's unlikely you want to know how far a trip you can go on with the 8 gallons left in your tank. Furthermore, it's not convenient for comparing operating costs either. You drive your car a certain number of miles per month, not a certain number of gallons. If I want to compare three cars that get 20, 30, and 40 mpg, the cost savings between the first two is bigger than between the last two -- despite the same change in the number. Basically, every time you use mpg, you have to do a division -- not the hallmark of a convenient unit.
None of that justifies heating with electrical resistive elements. There are two flaws to your argument:
1. You mix using gas with whole-house heating.
These shouldn't be mixed. You can have a whole-house gas furnace, or you can have gas units (or a gas fireplace) in critical rooms. Likewise, you can have a whole-house electrical system, or one per room. Or, you could have electronically-controlled baffles for your air distribution, which cost relatively little but allow you to direct airflow to only specific rooms at specific times of day.
2. You are advocating resistive heating as efficient.
Resistive heating can be 100% efficient: every watt you purchase becomes a watt of heat in your room (until it leaks out the window).
But that's not efficient for heating. A heat pump uses the watt of energy you purchased to perform work, moving heat contained in the colder, outdoor air to the warmer, indoor air of your house. The net effect is that each watt you purchase can translate to 3-4 watts of heat in your room. While clearly not accurate syntax, a head-to-head comparison would call such a heat pump 300 to 400 percent efficient, significantly better than the mere 100% your resistive heater generates.
Then you can use electronic baffle control to direct the heat just to bedrooms at night, and result in an overall system that is quite efficient and doesn't rely on one particular fossil fuel to function.
disclaimers
My house heats with natural gas, and we have an electric heat pad on our bed for cold nights. In other words, we do exactly the things I advocate against. That doesn't make them right, it just makes my actions wrong.
It doesn't hurt to be nice.