61-Watt Solar-Powered PC: Storage Batteries Allow Operation In The Dark, Continued
At a level of around 62 Watt-hours for a one-hour usage period, energy consumption for our solar-powered PC is sensationally low. Those who want to work all day long without plugging into the power grid, though, must purchase solar cells that can generate 1.5 kWh.
Total energy consumption of the solar-powered PC: 61.23 Watts
When the weather is bad, solar cells deliver little power; at night, they don't produce anything. Providing power during such periods requires a storage battery. During the day, when the sun is shining, the solar cells provide energy for the PC, and also charge the storage batteries as well. At night, the PC draws the power from the batteries.
Not looking too energetic: when the weather is lousy, solar cells don't deliver much energy
Solar cells can only deliver energy during roughly half of each day, so the batteries must be able to power the PC for around 12 hours (the other half of the day). We therefore determined that we would need storage capacity of around 1.5 kWh from our battery. It operates at 12 V, which requires a capacity of 130 Ah at 1.5 kWh. We also took into account the fact that transporting energy over a distance as short as 50 feet (15 meters) requires incredibly thick power cables to avoid excessive power losses.
Complete system, including monitor
In the next installment of this article series, we provide a step-by-step description of how we built our solar-powered energy collection and storage system.
Please continue by checking out the other parts of this series:
- Do-It-Yourself Solar-Powered PC: Technical Foundations
- Do-It-Yourself Solar-Powered PC: Solar Components
- Do-It-Yourself Solar-Powered PC: Live Test