Monday, February 28, 2011

Bus Blog 10: Solar Experimentation

I was trying to use everything I could find around my shop in the bus.  We were planning on moving soon and clearing-out without wasting was the mode of the mind.
I had originally planned to cover the rear windows of the bus with a sheet of 16 gauge steel and paint it to match the rest.  This seems to be a more traditional step in the anything but traditional world of bus conversion.  Covering/removing the windows not only provides a sleek, uniform exterior but protection that exposed glass does not easily provide.  The plan was set so I bought and cut a steel sheet to size and then, of course, found the solar panels.

I had paid 10 dollars each for a dozen submarine sandwich sized 12 volt solar panels, which now sat in a dusty box in the basement.  The first week with them I set up a series of experiments, drunk and giddy with the potential that solar power provided.  I read everything I could, growing to understand how they work and what is required to incorporate them into a functioning system.  Then, as usual life got in the way, rent was due, deadlines approached, things needed attention.  I had been re-purposing lamps and furniture from discarded material for years and really wanted to add solar technology to my work, but I already had suppliers and experience working with household current.  I set the panels aside, thinking, "One day."

I consider moving into a school bus a bit transformative.  You have to get rid of the extras and define your future goals.  When I had extra time, I'd go through my workshop, approaching half-finished projects with a temperament that began as nostalgic trepidation and ended as ruthless marauding.  I'd start gingerly placing things in boxes (just in case), but eventually end-up just burning stuff and drinking beer.  Separating ourselves from the past and old ideas is never easy, but beer and fire help, especially if it's cold out.
"Throw another one of those on the fire, it's cold."
"What is that, anyway?"

The solar panels were different, I could use them.
After a bit of testing, I found 7 had the output I liked.  Instantly, the bus design changed.  Why not?  I could always just cover the windows up from the outside...

Using silicone, I glued the panels to the windows I planned to cover, painted the glass around them black (not the best choice, but I really wasn't concerned with esthetics) and used ply cut-offs to hold them in place until dry.

Of the paints I tried, the spray enamel worked the best, and even though it looks bad from the inside, once covered by insulation, the windows look jet black from the exterior.  The acrylic I used was a bad idea, live and learn.  Since the windows are set out from the walls, brought the surface flush with 1/2" styrofoam, then proceeded to insulate as I did the floor.

Since the floor was a load bearing surface and needed to be very flat, I used the best of the poorly cut insulation I had purchased.  The rest, went on the walls.  The Styrofoam cut and slipped into the frame easily.  I'd deal with the proud bits later, for now, I just wanted everything to fit, next up was the ceiling.

The way I look at solar energy is it's free.  The average solar panel has a twenty to twenty-five year life span, often guaranteed, and on average, commercially available units take 10 years to completely offset their costs.  This means that for a one-time investment returned in 10 years, you can receive an additional 10-15 years of free power production.  Now consider that 25 years of service coupled with a 6% inflation rate and annual increase in purchased energy costs.  Has your power company ever charged you less per kilo-watt-hour than than the year before?  Doubtful.
Since technology is poised toward efficiency, requiring less energy per device, and since our bills only increase, being self reliant in terms of power production makes sense, and seems to be getting easier.

My small DIY system may not be enough to run every household appliance, but it supplies enough electricity to power the interior lights and a computer through the night, which is alright with me.  I plan to install a much larger system toward the end of this conversion, check out my dream panels: PVL136 UniSolar 136 Watt PV Flexible Solar Panel Laminate - Easy Installation - Peel & Stick