There are a number of variables that affect the amount of solar power a laptop needs. Before choosing any option have a look at all the possibilities. The method you choose will depend on the kind of activity for which the laptop will be used as well as the size and age of your laptop.
If you only use the computer for an hour or so a day or your laptop is a super efficient model... you're in luck. The less power you need to generate the more of the options below are available to you.
As you add needs such as portability or (like me) you need to power the computer for as many as 8 hours a day your choices become more limited... and more expensive. The more hours you need the computer to be powered the bigger the solar charger you'll need.
Laptops that qualify to display the energy star logo have been proven to sip rather than guzzle electricity. Apple, Dell, Lenovo, Gateway, Hewlett-Packard, Toshiba and Acer all include an energy efficient model in their lineups.
To keep it green we don't recommend chargers that don't allow for the replacement of the battery. Batteries have a much shorter lifespan than solar panels and discarding an entire unit beacuse the battery has reached the end of it's life doesn't make good green sense. Planned obsolescence is not in the planet's best interest.
Below we have several options that cover a wide spectrum of possibilities for powering a laptop with solar energy.
Consider the Following Before Adopting a Solar Power Laptop Solution
- How Many Consecutive Hours of Use ? Will you use the computer every day? How many hours? If you're just checking emails and using the laptop for 30 minutes or less per day and you have an energy efficient computer you can get by with a 10 to 20 watt system. Used for topping off the battery during the sunniest part of the day a solar charger of this size will not produce enough power to run most computers. With the onset of energy efficient laptops, smaller and more portable options will soon exist.
- How Many Watts Does Your Computer Need ? In general the bigger and older your laptop is, the more of a power hog it'll be. The recent introduction of mini, low energy laptops will make it easier to power laptops with solar in the future. Look for the Energy Star logo when replacing your laptop.
- Portability If you're exploring the Himalayas or on a tenting excursion one of the more portable solar power laptop options will suit you best. When you're further away than your extension cord can stretch, portability matters. Thanks to the introduction of thin film photovoltaic technology there are several foldable or rollable solar panels that can supply enough solar power to keep you in touch and ready for anything when you "go remote".
- What Kind of Activity? Collecting e-mails and creating text documents require less energy than uploading photos and video or burning DVD's and playing games. If you'll be doing high consumption activities get more power. A solar power laptop is probably not the best choice for game playing.
- Extra Attachments Extras such as external hard drive's, DVD players etc will increase the power demand when they're attached to the laptop. Unplug all devices that are not necessary for the immediate task.
- Running while Charging If you want the holy grail solar power laptop charger - one that will run and charge the computer at the same time - you'll need some serious wattage. 50 plus watts depending on the other variables discussed on this page. I use 60 or more to keep the laptop (Macbook pro 17) along with an internet card from a local cell provider, running for 8 hours most days .
CT Solar carries a line of serious portable chargers powerful enough to operate and charge most laptops along with extra attachments.
- Charge Controller Many solar chargers put out as much as 20 volts which can damage your battery. A charger controller installed between the panel and battery regulates the charge going into the battery.
Solar Power Laptop Options
- Hook the Laptop into a Home System Adding another panel to an existing array is a permanent way to ensure laptop solar power. If you already have a solar system it may be capable of supporting another panel. If you want to simultaneously run the computer and charge it on a regular basis go with 50 or more additional watts.
- RV, Boat or Cottage Power Install a small solar power system on your rv, boat or vacation home to power your laptop. I'm on the computer for several hours most days on our boat and use at least 60 watts. The 2 biggest draws on power aboard are the fridge and the laptop. More about solar sailing
- Vehicle Hooking up your solar power laptop charger to your vehicle's battery is a good portable solution for keeping a laptop charged. The solar panel can be laid out on the roof, hood or windshield of the car to soak up the solar energy and deposit it into the car's battery. You'll need an adaptor (12 volt adaptor available at automotive stores) so that your computer is able to use the DC energy from the battery.
- Serious Solar Charger Kit If you're serious about powering a laptop with solar energy, don't get anything less than a 50 watt system. Even with 50 watts there'll be times, such as cloudy or high use days, when your system struggles to make adequate energy . More is definitely better if you need to ensure that critical functions are uninterrupted.
- Flexible solar charger 20 - 40 watts for mini low power computers or 50 - 70 for power eaters. When traveling by vehicle, motorcycle, bicycle or foot, the more portable and lightweight the better. There are numerous super portable options on the market that fold or roll into easily stowable dimensions. A laptop can not be plugged directly into a solar panel, they are not compatible unless the laptop has a 12 volt adapter or a power center stores, converts and distributes the energy. When you make your purchase ensure that you also get a 12 volt adaptor or a power center to manage the power.
- Small Solar Charger Kit These compact, attractively packaged chargers work for some small electronics but anything less than 10 - 15 watts is disappointing for laptops.
- Solar Laptop Bags and Carriers. Backpacks and laptop bags are currently being marketed. As funky as those 4.5 watt solar bags are, they might be suitable for cell phone or GPS charging and topping up but it would take 4 or 5 days to fully charge a laptop battery with 4.5 watts of energy.
A 14 watt panel like those incorporated into Voltaic System's "Generator" bags will power a laptop for between 1 and 2 hours... but not while it's running. These small generators are placed in the sun for 4 to 5 hours and even then only produce enough energy to power the laptop for between 1 and 2 hours ideal solar power laptop solution for those who need the computer for about an hour per day. It'll keep the laptop topped up and will recharge most batteries with 2 or 3 days of good sunlight.
- Self Contained Solar Power Laptop Yes, they're out there but do they work? As always, it depends on what you want. The small panels included in these laptops can extend the length of time on a battery charge but are unlikely to produce enough power to run anything but the most basic program.
The size of the panel, when it is incorporated into the design of the laptop, is necessarily, limited by the size of the laptop. If you're dreaming of sitting in a sunbeam that feeds a stream of energy directly to your computer, keeping the battery topped off while running the laptop... then you're going to be disappointed. In order to do that solar panels (at their current efficiency levels) would have to be 3 to 5 times the size of the computer. You can see the dilemma here. Tiny panels = tiny power.
It will happen though, as solar cells become more efficient and laptops become more energy efficient the gap closes. The solar power laptop prototypes look very promising and well thought out.