Step 1: Power Requirements

We prototyped one system for this installation. The power requirement for this system is detailed below. It is important to not only understand the power consumption, but also the various voltage breakdowns and their associated power requirements. Additionally, it is important to acknowledge the fact that we want 24x365 uptime.

Step 2. System Diagram

Below is a basic schematic diagram for a solar power system. In reality the load should have a DC-DC convetor on it to adjust and regulate the voltage coming from the batteries. However, if you know the tolerance range of the equipment you could always set LVD (low voltage disconnect) and HVD (high voltage disconnect) to the applicable limits. It is also important to remember this is a simple diagram and the battery array should have some blocking diodes so if one battery dies it doesn't kill all of the batteries. It is also very important to think about the voltage of the solar array and batteries as higher voltages tend to lose less power due to wire resistance. HVD is to protect the equipment should the batteries be disconnected accidentally. LVD is to protect the batteries so they will not be completely drained (it then reconnects when the batteries get recharge to a high enough level).

Step 3. Components

Below is a list of components we selected for our setup. Many solar companies have programs to calculate how many solar panels / batteries you need. They require several specific pieces of information:

• Location (lat/long, elevation): N33.3 W116.9, 5000 feet
• Continous Power Drain: 31.25
• Prefered final output voltage(s): 12v
• Physical Issues (pole-mount, roof-top, etc.): Pole Mount 4" (I.D.) schedule 40 (side of pole mount)

Additionally, we chose to go with a combined charge controller and load controller as opposed to aquiring each part individually.

Step 4. Final Design Diagrams

Implementation 1: Low Power

The work on this project was completed by Todd Hansen for NLANR. This work is funded in part by NSF Cooperative Agreement No. ANI-9807479