Two Letters Re: Living with Photovoltaic Power

Good Day James,
I have been a daily reader of your blog for who knows how long and enjoy it everyday. I am not an electrician, but I did check with a good friend who has his PhD in electrical engineering. Should him this paraphrase of D.P.’s post regarding System building note and he said: “Bull.” Per the National Electrical code Article 250 on grounding, “You’d- Better ground your system” if something happens to him or his house regardless of how he is powering it (solar, grid tie in, wind, et cetera) if a  fire or electrocution happens to him or someone else he will not be covered by insurance. And if for some reason someone dies, well then I would hate to see what happens. Just a word of caution to your other readers. – The Boondocks

Reading Living with Photovoltaic Power by D.P. he mentions how his laptop power consumption is high, and suggest a tablet. While I agree a tablet is a great low-power solutions, there are a few key things that can make laptops consume substantially less power:

1. Put in an SSD drive.

A solid state drive (SSD) is a hard drive equivalent with no moving parts. That means no motor spinning metal plates at 4,000-7,000 rpm. They are becoming quite popular and their price is coming down. I recently put one in my wife’s laptop, and not only does it run notably faster (there is no seek time for physical magnetic needles, because there aren’t any) but she also thought I put in a new battery because she got so much more life out of it. Of course I didn’t replace the battery. The SSD consumes significantly less power.

2. Avoid processor-intensive operations.

Running a web browser or word processor requires an almost negligible amount of processing on modern computers. Games that involve a 3D environment eat a massive amount of power as evidenced by your laptop trying to burn a hole in your lap. This can also apply to useful programs like Google Earth. Obviously if you avoid the programs that tax the processor power consumption will be significantly lower.

3. Keep your screen at it’s dimmest setting

I recommend doing most of your computer time at night, so that you can run your screen at it’s dimmest setting. Don’t try this during the day, unless you have a dark room, or you’ll go crazy. At night a dimmed screen is very bright, and the power consumption is significantly less.

I don’t have hard numbers, but taking these steps will likely at least halve the laptop’s power consumption. – J.D.D.

JWR Replies: Thanks for those suggestions. I’d like to add that if your laptop is equipped with a wireless Internet card, then turn it off. That also draws substantial current.