Carbon diet
It is called "Mountain top removal"
def: Mountain Top Removal
February 2006
I don't approve of people destroying Appalachia so we can heat our houses with electricity from coal-fired power plants. So I am putting myself on a low carbon diet.
Conservation begins with data collection
I have to establish a baseline of our current energy use. I will need to log electrical use and temperatures over a period of time.
My house uses gas (and optionally, wood) for heat. It has an electric stove and water heater. Only the antique gas/wood central furnace uses gas.
I can monitor its run time by monitoring the electrical circuits running to it. I don't have a good way to measure actual gas used other than gas meter readings. I suppose I could read the meter once a day and log it. For a simple gas-only furnace, one way to measure furnace use is to monitor the fans; when the fans go on, hot air is being pushed through the burner so the burner is running. My furnace complicates things by having both wood and gas sections, so I will have to address that. (Possibly by replacing it!)
I can install a data logger and current taps at the main breaker panel to get readings on the whole house. See Power measurement page.
Measurements using Kill-a-watt
Computers
HP Vectra desktop
- Astec ATX90-3405 SFX/MicroATX power supply [1]
- HP Motherboard
- RAM
(SFX has no -5V supply so is not ISA compatible. 90W is all the spec requires.)
Via EPIA 800
- Astec ATX90 power supply
Board by itself draws 29W with this supply
Adding the CD drive, draws 3W more when drive checks for CD then drops to 29W
Adding the Vectra HD, draws 34W at boot and then drops to 22W,
so the CPU must still be doing some work when it is unable to boot.
Spinning down the HD drops it to 19W.
What I'd like to do is load up a CF card with the operating system and have the hard drive hold only data, so when the system is idle the drive spins down.
Generic Pentium Pro 200 system
- Powerman 235W ATX supply with on/off switch
- Pentium Pro 200 Intel Mars motherboard
- Four 72 pin 32MB SIMMS = 128 MB
- No CPU fan (power supply fan directs air directly onto heatsink)
- Tulip network card (est 2W)
- Soundblaster Model CT4180 card (2W)
- Dual port Intel network card (3-4W)
- Dual port SIIG USB 1.0 card (2W)
- Trident video card (ISA) (3W)
- Intel Mars motherboard PIIX chipset
- PS/2 keyboard (no difference on power reading w/o keyboard)
- IDE hard drive: IBM Deskstar 15 GB IBM-DTLA-307015
Boot: 55-60W, peaks to 70W
Idle: 36W
HD spun down: 31W
Stripped down: MB + 128MB RAM + HD = 23 W
Spinning down the hard drive saves 5 watts
Power supply has OFF switch; with the various and sundry network cards installed it burns
PS fan and CPU fan died years ago so I put the high quality fan from a Sun 3 workstation into the supply and dumped the CPU fan. CPU does NOT get hot under normal operation.
CDROM drives
Only needed occasionally; I can leave a drive in the system but unhook power to it.
- Diamond 8X CDROM: 1 W when idle (no disc in drive)
Mini-ITX
The system tested above based on the Via board is in the Mini-ITX form factor. There are "fanless" and "fan" versions with 500 and 800 Mhz processors. I currently use an 800 Mhz board with a fanless Zalman BZ-47 Northbridge heatsink and the case / power supply fans provide adequate cooling.
I monitor temperatures and turn down the fans using a controller from Sunbeam. This gives me a front panel readout only, no way to monitor from the computer.
C7 upgrade
The C3 processor on the Via 800 Mhz card is basically a Pentium instruction set.
The new C7 processor has an advanced instruction set and it's faster. Does this mean it uses more power? Or is it more efficient. I have gotten a CN10000 board from logicsupply.
The new board is now installed in a case. For more information, see the 8track page.
CPUFreq
Turn the CPU speed down when you aren't using it!
Two options are cpufreqd amd powernowd I am testing powernowd.
I installed powernowd from the Debian package.
For the C3 processor, enabling speed control means loading the 'longhaul' module and one of the governor module. For powernowd, the governor to use is 'userspace'. From the command line,
modprobe longhaul modprobe cpufreq_userspace
Look in /proc/cpuinfo to see the current CPU speed. Right now I see
processor : 0 vendor_id : CentaurHauls cpu family : 6 model : 7 model name : VIA Samuel 2 stepping : 3 cpu MHz : 400.094 cache size : 64 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu de tsc msr cx8 mtrr pge mmx 3dnow bogomips : 800.57
It's cut the CPU speed to 400 Mhz (normally it is 800.) Now I can drive up the load by playing a movie and check again. Sure enough! When the movie plays I see the cpuinfo report
cpu MHz : 800.189
NOW... I need to know more accurately just how much power this baby is using. I need some instrumentation! Power measurement
