A Week Off The Grid
By marchamilton on Aug 05, 2009
For those who are not familiar with eSolar, it is a Bill Gross startup from Idealab and described more in today's Los Angeles Times article.
Knowing that I had a rare week with no travel, I decided last weekend to do a little father-son project and install my own small solar system, thinking at first it would be just the thing to run my teenage son's various portable devices and perhaps the small aquarium in his room. I had been eying the Sunforce 60-watt solar charging kit at Costco my last several visits and decided to take the plunge (Amazon.com carries the kit at a similar price, with free super-shipping and six months interest-free if you use your Amazon charge card, although that didn't work for my weekend impulse buy). The kit includes everything you need to for a small off-grid system except a battery, including all cables, a battery charge controller, and a 200 watt inverter. With the usual caveats, you should even be able to claim the 30% US tax credit for the kit.
So our Saturday started with assembling the PVC frame for the 4 solar panels in our garage. Unfortunately, the factory sealed box was missing one of the PVC pieces needed to complete the frame and I had visions of the rest of the day spent in Costco's return line trying to get an exchange. Luckily, when I returned around noon, a Costco manager was able to promptly help me and took the missing piece out of another box and I was on my way in less than five minute, now that was a pleasant surprise! On my way out, I stopped by Costco's automotive center (separate entrance, separate cashier, no waiting) and purchased a deep-cycle marine battery.
The 200 watt inverter is plenty to run my laptop, cell phone charger, and the small aquarium pump. With no travel and no in-office meetings, I have not had to use my car for work this week, further lessening my carbon footprint. My only complaint is that the 200 watt inverter has a small noise fan that runs continuously when turned on so next weekend's project is to replace it with a larger, 1500 watt inverter that has thermostatically controlled fan.
Knowing just enough about data center Power Usage Effectiveness (PUE) to sound impressive at cocktail parties, I realized running the AC inverter only to then have my laptop power adapter convert back to DC was not efficient, so as my Mac laptop battery approaches a full charge, I've been unplugging the inverter and plugging my laptop DC adapter directly into the battery power cable, which avoids an energy-burning DC-AC-DC cycle. The one lonely fish that has survived my son's mostly failed attempts at fish care over the last year doesn't mind that its water is only filtered part of the day!