Basic wiring diagram of a simple solar power system

Solar power systems vary widely in their power producing capabilities and complexity.

You might say that the cost of implementation is somewhat proportional to that.

However there’s a common thread among most of them: The basic building blocks of components.

1. Solar panels
2. Charge controller
3. Battery bank (if off-grid or standalone system)
4. DC to AC inverter for AC power

 

Solar Power – System Diagram

I’m posting this for the beginner. The basic diagram. And an example.

The basic solar power system diagram (minus the various circuit breakers, combiner boxes, cables, shunts, grounds, and other details).

 

First, Is Solar Power Worth it?

First, lets face it… To implement solar energy is not cheap compared to today’s energy from the grid. Though the costs are coming down!

One could argue that from a cost savings point of view it’s not very practical.

It may take years to reach a break-even point. Why? Because a cost analysis of a solar power system compared with that of your electric utility bill will speak for itself.

Depending on the system design and usage, the break even point varies widely.

 

Worthwhile for Many!

Despite the cost of a given solar power system, for many it’s a worthwhile investment.

Example: If purchasing a new property with land far from the nearest road with electric utilities, it may actually (very likely) cost less to implement a solar power system than pay to run electricity to your property.

For the preparedness minded, simply having a very basic solar power system (or bigger) provides some peace of mind (at least it did for me).

 

A Basic Solar Power System

Without going into great detail, I thought that I would illustrate a very simple and basic solar power system diagram:

solar-power-system-diagram

 
Here’s a simple small 300 watt solar panel system with a 600 watt DC-AC inverter, just for an example:

You could utilize (3) 100 watt panels listed below.

According to the specs of these particular panels, the combined paralleled output would be about 20 Amps @ 12 volts DC.

The referenced charge controller would be an appropriate size for this. Though they’re available in all sorts of specifications.

The charge controller would be connected to any number of 12-volt deep cycle batteries wired in parallel (the more batteries, the more energy storage).

Optionally you could add a DC to AC inverter to power 120 volt AC devices.

 
100 watt solar panel, 12 volts DC from Renogy
Renogy 100 Watts 12 Volts Monocrystalline Solar Panel
100 watt, 12 volt solar panel from Renogy

 
Connect the 3 panels (above) in parallel using these adapters:
MC4 T Branch Connectors
Combine 3 solar panels with MC4 splitter
This MC4 splitter will enable parallel connections of the panels listed above. Their specs will combine and add up to about 20 amps. This will maximize the usage of the charge controller listed below.

 
20 Amp 12 volt DC Charge Controller by Renogy
Renogy 20 Amp 12V/24V DC Input MPPT Solar Charge Controller
20 Amp solar charge controller by Renogy

 
Renogy connection diagram
Solar Panel connection diagram from Renogy

You could run 12 volt DC powered devices from the basic solar power system above.

Or you could add a DC to AC inverter to power 120 volt AC powered devices, not to exceed the rated output of the chosen inverter.

For example you might choose this 600 watt inverter:
Samlex America Pure Sine Inverter, 12V, 120 Vac, 600W
Samlex 600 watt inverter 12 volts DC input

 
SUMMARY
It’s not terribly difficult to assemble a basic solar power system. Though it really helps to have an understanding of basic electronics and electricity!

You might think that the simple example system listed above (300 watts input, 600 watts output via battery bank storage) isn’t very much power.

However if that 300 watts of solar panels were charging a battery bank for say, 6 hours? That would equate to 1,800 watt hours of energy (1.8 kWh). Note, the battery bank would need to be sized appropriately.

See how that works? That could be enough to operate some essential systems.

 

Reference Books for Solar Power

If you’re interested to research this further, it would be beneficial to read up on the subject. Here’s a listing of books which may help:

SOLAR POWER REFERENCE BOOKS

 
Continue reading: The Four Essentials of Off Grid Solar

Read more: ‘Kill A Watt Meter’ — How to Measure Power Consumption (kWh)

Solar Power and Energy Requirements – How To Calculate Your Needs

 
I originally posted this article back during 2011!
I’ve updated and edited it a bit, and republished for your potential interest.