A wise frog once said, “It’s not easy being green.”
This was obviously said after a solar power equipment cost-benefit analysis. We want to do our part to help the environment, but it would be nice if we could save money at the same time.
I had the seemingly brilliant idea, “What if my laptop was green? I want a solar powered laptop! And I’ll use solar power to charge rechargeable batteries and my cellphone. If I buy a couple of cheap solar panels, I could power all these devices and save big money on electric bills!”
“Seemingly brilliant” could also be read as “completely wrong”. Despite what I thought, saving money via solar power is harder than it sounds. If you’ve ever wondered, “Does solar power save money?”, at least for small devices, the answer is “no”.
Go to www.brunton.com, and look at the “Portable Power – Solar Panels” section. Brunton is one of the top providers of quality consumer solar power products. For examples, see the SolarPort ($120), or theSolaris ($400). The SolarPort is made for charging and powering small devices, while the Solaris is meant for larger units like laptop computers. Both can be chained to other solar units to provide more power.
Bear with me for a moment while I spout some numbers and math.
Based on my last electric bill, I pay about eight cents per kilowatt hour, or almost two-tenths of a cent per watt per day. So for my smaller electric devices, I pay fractions of a penny per hour to use and charge them.
To figure out how many watts your laptop, charger or other electric device uses, look at the power adapter. You should see electric output information, the amount of juice sent to your device. Taking my IBM Thinkpad laptop as an example, I see it requires 16 volts and 4.5 amps, written on the adapter as “16V 4.5A”.
To find electric wattage use, multiply volts by amps. If your device specifies “mA” instead of “A”, multiply the mA (milliamps) value by .001. Using my example, my laptop slurps up 72 watts. Using the rates above, my laptop costs me about half a cent per hour to use, or fourteen cents per 24-hour day. For comparison, my cellphone charger requires 5.2 watts, and costs about a penny per day.
I took some time to think (okay, LOTS of time, I hate math): Typing furiously on a calculator and staring confusedly at figures of wattage requirements and what I pay for them, I eventually realized something interesting.
If I want to use solar power to charge and use my laptop, I’d want to use it enough to pay for the $120 SolarPort. The SolarPort is actually underpowered for a laptop, but I’m being generous here. To make up the savings with solar power, I’d have to use my laptop for 857 days. That’s over two years of continuous, twenty-four-by-seven usage. If I’m using it to charge my cellphone, I’d have to charge for almost 33 years to make up the cost!
So saving money with these devices is not realistic. Their use is for safety and convenience. Use them when camping, out at the beach, or anywhere you don’t have easy access to an electric socket. I’d much rather play with my toys outside than be stuck indoors.
No, Kermit, it’s not easy being green. When used with smaller devices, solar power won’t save money, at least in the near future. This will hopefully change someday, but until then there is still a major benefit: Solar power ranges from a big convenience to a life saver. Let the sun shine.
Marty adds a very important point:
I enjoy your column often. I especially enjoyed your article on solar powering small devices such as a laptop. I have to say though that although you’re very right from a financial perspective – It WILL take a long time to pay off the cost of the solar panel through the money you save by using it… I think you might have missed true benefit of solar power. I think the point is that by using solar panels you are no longer using up non-renewable resources. Even if its only on a small scale. I think that type of thinking (with $$ being the bottom line) is the sole reason these technologies haven’t been more widely accepted. You can’t put a price on our planet.. blah blah i know.. it sounds cliche. But we’ll all realize the scary reality of all this someday.
Anyway, love the column. Thanks for hearing my opinion.
I agree 100%. Yes, small-scale solar power isn’t worth it, if you’re trying to save money. But the principle of this thing is also important. In addition, we should indeed be focusing our economy hard on alternative power. Too bad those in control think there’s no pressing reason to do so.