| First, I'll start by saying that photos you see of laptop | | | | can run a 1-Watt GPS direct from a solar panel on a |
| computers plugged into solar panels is misleading, but is | | | | cloudy day, because even on a cloudy day, a 5-Watt |
| typical of photos you will see around the internet on | | | | solar panel should be able to provide 20% of its peak |
| sites promoting solar power. The truth is... you cannot | | | | output (ie 20% of 5Watts = 1Watt). |
| usually charge a laptop directly from a solar panel. | | | | But what do you do when the device you need to run |
| Why? | | | | is larger than the peak output of your solar panel? |
| 1. The output voltage of the panel probably won't | | | | How can a 10-Watt solar panel power a 30-Watt |
| match your computer | | | | computer? |
| 2. The panel likely doesn't come with a connector for | | | | Simple, put the solar panel out all day connected to a |
| your computer | | | | battery so that all the solar power collected will be |
| 3. Laptop batteries are not easily charged from a | | | | stored in the battery. Equipment can then be |
| passive source like solar | | | | connected to the battery as needed - batteries are |
| 4. You certainly cannot 'run' a 30 Watt device from a | | | | typically able to release more power than was used to |
| 10 Watt power source | | | | charge them, and only their capacity will dictate how |
| So, how can a solar powered laptop be created? | | | | long you can run from them. |
| Actually, it isn't too difficult, but it does require a little | | | | 3. Give the stored power to the laptop |
| planning. | | | | Let's avoid AC power if possible... |
| So here it is. Step-by-step. | | | | An AC inverter is a small device that converts battery |
| 1. Choose a solar panel to match your power | | | | power to household outlet "AC" power. |
| consumption | | | | AC power is something you will want to avoid in a |
| We'll assume that your laptop is like most others, and | | | | portable power application if at all possible. It is |
| consumes about 30 Watts while it is running. Some | | | | documented in other areas of our website how an AC |
| laptops with big dual processors etc can consume up | | | | inverter is quite inefficient, and requires system support |
| to 100 Watts if they are burning DVDs or other | | | | that makes portability a bit difficult. |
| intensive operations. But for our purposes, and | | | | The other, more desirable option is to use a voltage |
| assuming that you are a practical person who knows | | | | converter to create the power your laptop needs. |
| how to dial back their power settings, we will go with | | | | Whether you are wanting to charge directly from the |
| the standard number of 30 Watts continuous. | | | | solar panel, or via your solar power storage battery, |
| Now, you need to determine your usage time. | | | | the voltage converter will provide the proper voltage |
| How many hours a day do you absolutely have to | | | | for your computer's battery system. |
| have on the computer? The bare minimum now, with | | | | In conclusion... |
| no coffee breaks. If you use the computer for 1 hour | | | | Creating a portable solar power system using flexible, |
| each day, then you will need to offset 30 Watt-Hours | | | | foldable solar panels for extended expeditions with |
| with your solar panel, which will equate to a minimum | | | | your laptop computer requires some careful |
| 10 Watt solar panel for most areas (May-Sept). | | | | considerations. Choosing a solar panel that adequately |
| 2. Store the solar power | | | | offsets your power consumption. Storing the electricity |
| Sunlight & hence solar power is unpredictable. So | | | | you generate from the solar panel for later use and to |
| most good, reliable, solar power systems provide a | | | | moderate the variable power of the sun. And finally, |
| means of storing the power produced by the panel so | | | | use a voltage converter, or AC inverter, to provide |
| that it can be used when & how it is needed. You | | | | your laptop with the correct voltage power. |