We connected the outputs from the solar panels directly to the PC, so it has 16 V DC of power at its disposal. Depending on the intensity of sunlight at any given moment, though, these modules output anywhere between 12 and 20 V DC. That's why we chose a very special power supply - namely, the M2-ATX from Ituner - that can handle input voltages in a range from 6 to 28 V DC.
The Ituner M2-ATX power supply
Top view of low-voltage power supply
Because this is a low-voltage power supply, the maximum rated power for this device is a scant 160 W. The input voltage to the PSU is also very close to the output voltage it needs to produce for a PC. This narrow difference between input and output voltages has the happy consequence of enabling extremely high efficiency, compared to a PSU that handles conventional A/C power. We use this power supply to drive all the components in our solar-powered PC, including the monitor.
The Ituner M2-ATX includes only a single 5.25" drive connection and a single SATA connector, so we used a Y-adapter to hook up the rest of our components.
We used a Y-Adapter to route power to additional devices in our PC
We measured the efficiency of the power supply in our solar-powered PC at idle, and under heavy load, as shown in the following chart.
Efficiency for our low-voltage PSU
- A New Desktop PC Power Consumption World Record: 61 Watts
- Power Delivery: Conventional A/C (120/230V) Or 16 Volts DC?
- Delivering 16 V DC From A Solar Panel
- Delivering 16 V DC From A Solar Panel, Continued
- Efficiency Is Where It's At
- Efficiency Is Where It's At, Continued
- Best Choice: AMD Athlon 64 X2 BE-2350
- 1 Watt Active Cooling Takes Very Little Power
- Energy-saving Motherboard: Gigabyte With HDMI And DVI
- Energy-saving Motherboard: Gigabyte With HDMI And DVI, Continued
- Comparing Energy Draw: MSI Vs. Gigabyte
- Motherboard Comparison
- Measurements: Energy Consumption For Onboard Components
- Major Differences Among Hard Disks: WD Comes Out Best
- Comparing DVD Drives: Samsung Wins With 3.5 Watts Consumed
- The Monitor Is A Real Energy Hog: 23 Watts When In Use
- The Monitor Is A Real Energy Hog: 23 Watts When In Use, Continued
- 61-Watt Solar-Powered PC: Storage Batteries Allow Operation In The Dark
- 61-Watt Solar-Powered PC: Storage Batteries Allow Operation In The Dark, Continued